It's hard to adopt something that schools don't teach. I know someone who graduated from UCI with a CompSci degree with a specialization in networking, just before the COVID19 pandemic began. He recalled that the networking courses he took did not cover IPv6 at all, except to describe the address format (i.e. 128 bits, written as hexadecimal, colon-separated). Everything he learned about IPv6, he had to learn on his own or on the job. A standard that has been published for over two decades, heavily used for over a decade, and critical in the worldwide growth of the Internet, was treated as an afterthought by one of the premier universities in the US.
Obvious disclaimer: This is a sample size of 1, and an anecdote is not data, yada yada. I'm not involved in academia, and have no insight into the adoption of IPv6 in CompSci networking curricula on a broader level.
Tbh it’s is a huge PITA with little practical benefit. IPv6 is the Perl 6 of networking.
Many of the big benefits are things that don’t deliver anything that folks are lacking. You also need to understand how you fit in the overall universe more.
Meanwhile, I was taught and practiced IPv6 in 2003-5 in engineering school (France).
As of 2024, IPv6 deployment in France was >97% mobile and >98% residential due to not being required for obtaining a 5G radio license (and then v6 simply carried downward to being available on 4G) + every ISP that provides FTTH also providing v6.
IPv6 was superceded by NAT a long time ago. It will die a slw and quiet death which is why it is now being ignored by training facilities and experts worldwide.
Digital Ocean didn’t even have an ipv6 address on by default in the droplet I created last week. It’s just a switch to flip, but I’ll bet the support costs of hobbyists/enthusiasts not realizing they needed to also write firewall rules, make sure ports weren’t open for databases and things like that for ipv6.
It's a "just doesn't work" experience every time that I try it and I don't experience any value from it, it's not like there isn't anything I can connect to on IPv6 that I can't connect to on IPv4.
My ISP has finally mastered providing me with reliable albeit slow DSL. Fiber would change my life, there just isn't any point in asking for IPv6.
Also note those bloated packets are death for many modern applications like VoIP.
Exactly. Spectrum delivers good IPv6 service in my area. I tried it when I upgraded my gateway. All of my devices are assigned 4 IPv6 IPs, hostnames are replaced by auto assigned stuff from the ISP, and lots of random things don’t work.
I went from being pumped to learn more to realizing I’m going to invest a lot of time and I could not identify and tangible benefit.
> those bloated packets are death for many modern applications like VoIP.
Huh? The packet sizes aren’t that much different and VOIP is hardly a taxing application at this point anyway. VOIP needs barely over dial-up level bandwidth.
My memory of IPv6 is getting waves of support tickets from people who took their (already questionable) practice of blocking ICMP on IPv4, blocked ICMPv6, and then got confused when IPv6 stopped working.
Yes as I said in a sibling post the telcos are the only ones using it, and that is the only reason that graphs like the google client one exist. That is only because it already exists and is cheaper than using NAT when you have hundreds of millions of clients.
> I would say its more "Wireless only ISPs are the only ones using it"
So… the largest ISPs.
Recent number show about 94% of Americans have cell phones and 92% of American households have Internet connections. In raw numbers, that’s about 300M cell phones and 111M households.
If zero fixed ISPs support IPv6, that’d still be about 75% of total Internet connections that do.
What are you even basing that on? Here are some facts:
- You have to pay money to get a static IPv4 address for cloud machines on eg AWS. Anything needing a static IPv4 will cost more and more as demand increases. NAT doesn’t exactly fix that.
- Mainstream IoT protocols have a hard dependency on IPv6 (eg Matter/Thread). Not to mention plenty of 5g deployments.
- Many modern networks quietly use IPv6 internally. I mean routing is simpler without NAT.
So it almost definitely won’t die. It’s more likely it’ll slowly and quietly continue growing behind the scenes, even if consumers are still seeing IPv4 on their home networks.
I run dual stack at home with dns64/nat64. I average 50/50 traffic v4/v6. Web browsing gets skewed v6 but large file transfers and some streaming pushed it back to 50/50 overall. My family would revolt if I went v6 only so I'm not sure I'd say its just there for holdouts. Major annoyances include any old device and my hue bridge.
No; most sites I reach from the phone seem to be reached via IPv6. E.g. hitting whatismyip.org exposes an IPv6 (though mentions an IPv4 because they're trying to discover that, too).
Some sites do not support IPv6; for those indeed there's a XLAT464 service.
People love this graph and regularly tout it as if it explains full internet usage. Especially when they dont bother to add any explanation or comment alongside it.
This graph is mainly due to the fact that telcos use IPv6 for mobile devices, nothing more. Over time you will see that graph flatline and peter out as mobile device uage reaches critical mass.
It seems more the other end of the stick: the IPv4 side of the graph is mainly held up due to corporations. The consumer internet continues to switch, but corporate VPNs are going to continue to drag down the numbers until corporations get charged enough for IPv4 address space that bottom lines start to notice.
Yep, and even with all those countries with their billions of mobile devices IPv6 use still hasnt even reached 50%.
Pretty much all ISPs hand out both IPv6 and IPv4 addresses to their clients, this is nothing new. When they start only issueing IPv6 IPs is when it would start truly taking off, but it will never get to that point and it will never happen.
It feels like you are constantly moving goal posts here. Your original statement was it will die a slow and quiet death. Are you now saying that this mobile use case will start to switch back to IPv4? It may not kill IPv4, like was initially planned, but it's not going away.
Devices maybe, software won't :-\ (We're going to see ever-diminishing pockets of IPv4 around for a loooong time, much like we still see pockets of Cobol.)
>> I know someone who graduated from UCI with a CompSci degree with a specialization in networking, just before the COVID19 pandemic began. He recalled that the networking courses he took did not cover IPv6 at all...
I am not doubting you, but I feel this story is too hard to believe without adding further nuances...
The issue is that it’s not taught with IPv6 first. Networking courses do all kinds of stuff using IPv4 to demonstrate various protocols on top (e.g. http, tcp, icmp, etc).
Then there is usually a chapter on IPv6 that just briefly covers the differences.
I.e. the exercises all tend to use IPv4 as the foundation so people don’t practice v6
But TCP or HTTP don’t care about the underlying transport. They’re higher level protocols that are payloads to either IPv4 or IPv6. It’s irrelevant what the transport is when dissecting HTTP and very little time should be spent on it.
IPv4 is, for all intents and purposes, still the default transport. It’s also simpler than IPv6 in some regards. When teaching layer 3, it makes sense to teach both, and teach IPv4 first. Though I fully agree that they should be taught with equal emphasis. I don’t doubt there’s a good number of programs out there that don’t into sufficient detail on IPv6.
I don't like to admit this, but at this point honestly I think ipv6 is largely a failure, and I say this as someone that wrote a blog post for APNIC on how to turn on ipv6.
I'll get endless pushback for this, but the reality is that adoption isn't at 100%, it very closely needs to be, and there are still entire ISPs that only assign ipv4, to say nothing of routers people are buying and installing that don't have ipv6 enabled out of the box.
A much better solution here would have been an incredibly conservative "written on a napkin" change to ipv4 to expand the number of available address space. It still would have been difficult to adopt, but it would have the benefit of being a simple change to a system everyone already understands and on top of a stack that largely already exists.
I'm not proposing to abandon ipv6, but at this point I'm really not sure how we proceed here. The status quo is maintaining two separate competing protocols forever, which was not the ultimate intention.
> A much better solution here would have been an incredibly conservative change to ipv4 to expand the number of available address space
"And what do you base this belief on?
Fact is you'd run into exactly the same problems as with IPv6. Sure, network-enabled software might be easier to rewrite to support 40-bit IPv4+, but any hardware-accelerated products (routers, switches, network cards, etc.) would still need replacement (just as with IPv6), and you'd still need everyone to be assigned unique IPv4+ addresses in order to communicate with each other (just as with IPv6)."[0]
> Fact is you'd run into exactly the same problems as with IPv6.
If you treat IPv4 addresses as a routable prefix (same as today), then the internet core routers don't change at all.
Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.
IPv6 seems to be a standard that suffered from re-design by committee. Lots of good ideas were incorporated, but it resulted in a stack that had only complicated backwards compatibility. It has taken the scale of mobile carriers to finally make IPv6 more appealing in some cases than IPv4+NAT, but I think we are still a long way from any ISP being able to disable IPv4 support.
> Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.
Congratulations, you’ve re-invented CGNAT, with none of the benefits, and the additional hassle of it being an entirely new protocol!
No. No “extra bits” on an IPv4 address would have ever worked. NAT itself is a bug. Suggesting that as an intentional design is disingenuous.
Hardware would catch up. And IPv4 would never go away. If you connect to 1.1.1.1 it would still be good ole IPv4. You would only have in addition the option to connect to 1.1.1.1.1.1.1.2 if the entire chain supports it. And if not, it could still be worked around through software with proxies and NAT.
So... just a less ambitious IPv6 that would still require dual-stack networking setups? The current adoption woes would've happened regardless, unless someone comes up with a genius idea that doesn't require any configuration/code changes.
I disagree. The current adoption woes are exactly because IPv6 is so different from IPv4. Everyone who tries it out learns the hard way that most of what they know from IPv4 doesn't apply. A less ambitious IPv4 is exactly what we need in order to make any progress
It’s not _that_ different. Larger address space, more emphasis on multicast for some basic functions. If you understand those functions in IPv4, learning IPv6 is very straightforward. There’s some footguns once you get to enterprise scale deployments but that’s just as true of IPv4.
The only solution is a gov't mandate. China went from almost no adoption to leading the world in adoption (77% of all Chinese internet users) in a few years because they explicitly prioritized it in their last 5-year-plan.
Circa 1999 I was working for Cisco as a sysadmin. I got my CCNP through internal training and considered making a career of network administration, but ipv6 changed my mind. It seemed so much more difficult and unpleasant to deal with. I didn't want that to be my day to day work.
I think the same thing happens on a different scale with ISPs. They don't want to deal with it until they have to for largely the same reason.
IPv6's failure was mostly caused by the IETF's ivory tower dwellers, who seem to generally have no practical experience or understanding whatsoever of how networks are actually built and run today, especially at the small to mid scale.
Small site multihoming, for example, is an absolute disaster. Good luck if you're trying to add a cellular backup to your residential DSL connection.
IETF says you should either have multiple routers advertising multiple provider-assigned prefixes (a manageability nightmare), or that you should run BGP with provider independent address space; have fun getting your residential ISP or cellular carrier onboard with this idea.
IETF has a history of being hostile to network operators. I mean actual network operators - not the people who show up at conferences or work the mailing list who just happen to get a paycheck from a company that runs a network (and have zero production access / not on call / not directly involved in running shit). It's gotten better in the last few years in certain areas (and credit to the people who have been willing to fight the good fight). But it's very much a painful experience where you see good ideas shot down and tons of people who want to put their fingerprint on drafts/proposals - it's still a very vendor heavy environment.
Even the vendor representatives are mostly getting paid to post on mailing lists and show up at conferences.
They're not building products, and they're not supporting, visiting or even talking to their customers. Design-by-committee is a full time job that people actually building things for a living tend to not have time for.
> a cellular backup to your residential DSL connection
Hmm, what's the problem? I suppose your home devices should never be exposed to the public internet, and should only be accessible via a VPN like Wireguard. NAT64 is a thing if your home network is IPv4.
BTW what's the trouble with multi-homing? Can't an interface have two separate IPv6 addresses configured on it, the same way as IPv4 addresses?
> BTW what's the trouble with multi-homing? Can't an interface have two separate IPv6 addresses configured on it, the same way as IPv4 addresses?
Because it breaks your network when that router goes away. Your switch ACLs, firewall rules, and DNS records all become invalid because they contain addresses that no longer exist, that your devices continue trying to reach anyway.
Ah, I understand what you likely mean saying "small site multihoming": not a Web site (where it would be trivial), but e.g. a small office.
But with multi-homing you would need to actively test which of your uplinks has Internet access anyway, won't you? And you would have to react somehow when one of your uplinks goes down.
It's easiest to do by abstracting your site away. Make it use a LAN, and do port-forwarding and proxying through a box that knows about the multiple uplinks, and handles the switch-over when one of them goes down. I don't see how it might be easier with IPv4 than with IPv6.
I still assume that you don't want the internals of your office network directly accessible via the public Internet, even when you easily can; VPNs exist for a reason.
You should be using dynamic DNS and firewall rules should be on the subnet boundary in this scenario, any decent firewall (including referee PFsense/OpnSense) support ACLs that follow IPv6 address changes.
The amount of ignorance in these ipv6 posts is astounding (seems to be one every two months). It isn't hard at all, I'm just a homelabber and I have a dual-stack setup for WAN access (HE Tunnel is set up on the router since Bell [my isp] still doesn't give ipv6 address/prefixes to non-mobile users), but my OpenStack and ceph clusters are all ipv6 only, it's easy peasy. Plus subnetting is a heck of a lot less annoying that with ipv4, not that that was difficult either.
I want to send my ssh via my low latency reliable connection, I want to route my streaming via another connection. That’s just a routing rule and srcnat in ipv4
That’s before you go on to using PBR. I want to route traffic with different dscp via different routes.
Ultimately I want the rout g to be handled by the network, not by the client.
I wouldn't say "failure". There are many, many IPv6 client devices out there, mostly on mobile networks. And it works great and they do well and the tools all support it very well.
But IPv4 will never, ever die. The rise of NAT as a pervasive security paradigm[1] basically neuters the one true advantage IPv6 brought to the table by hiding every client environment behind a single address, and the rise of "cloud everything" means that no one cares enough about reaching peer devices anyway. Just this morning my son asked me to share a playlist, so of course I just send him a link to a YouTube Music URL. Want to work on a spreadsheet for family finances with your spouse in the next room? It lives in a datacenter in The Dalles.
[1] And yes, we absolutely rely as a collective society on all our local devices being hidden. Yes, I understand how it works, and how firewalls could do this with globally writable addresses too, yada yada. But in practice NAT is best. It just is.
ipv6 adoption is still steadily rising. Not as fast as anyone hoped, but at least steadily. There is no way it can be abandoned at this point even if we wanted to.
I wonder if it could still be usurped by another standard that is somehow more popular. If adoption of that leapfrogs over IPV6 then maybe it will have just been a waypoint along the way.
Stripped of all the other baggage that came with it (e.g. SLAAC, IPsec, etc) IPv6 is an incredibly conservative addressing extension. The only thing even more conservative than v6 would have been to drop the lower 64 bits of the address and the associated EUI-64 local addressing scheme. Which... to be fair, that turned out to be a very bad idea, but the length of the field isn't what was holding up v6 adoption.
I suspect by "incredibly conservative" you mean "backwards compatible", which... no. You can't make an addressing extension backwards compatible with hardware that doesn't read all of the address. Of course, we did that anyway with CGNAT, and predictably it causes huge problems with end-to-end connectivity, which is the whole point of IPv6. You're probably thinking more along the lines of an explicit "extension addressing header" for v4. Problem is, that'd mean a more awkward version of IPv6's /64 address split[0], combined with all sorts of annoying connectivity problems. The same corporate middleboxes that refuse to upgrade to IPv6 also choke on anything that isn't TCP traffic to ports 80 and 443. So you'd need Happy Eyeballs style racing between CGNAT IPv4 and "extended IPv4".
Also, that would just be a worse version of 6in4. Because they also thought of just tunneling IPv6 traffic in IPv4 links. I don't think you understand how incredibly conservative IPv6 actually is.
The problem with "incredibly conservative" IP extensions is that nothing beats the conservatism of doing literally nothing. IT infrastructure is never ripped out and replaced unless there is a business case for doing so. The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic", they've only said "let's get more dual-stack hosts online", which is a process that only asymptotes to 100% IPv6, and never reaches it.
IPv4 was not the first version of the Internet protocol. That honor goes to Network Control Protocol (NCP). The reason why we don't have an asymptotic long tail of Internet hosts still demanding NCP connectivity is because this was back when "having a connection to the Internet" meant "having a connection to ARPANET". The US military could just refuse to process NCP packets and actively did this to force people onto IPv4. Now imagine if someone big like Google said "we're going to stop accepting IPv4 connections" - people would jump onto v6 immediately.
[0] Let's say we add a 32-bit extension header onto IPv4
> The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic"…
One of the giant CDNs translates all IPv4 traffic to IPv6 at the edge (stateless NAT46) and is IPv6-only in its core network (for one of its primary product networks; like everybody they have multiple networks.)
> The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic"
Mobile carriers have done that between consumer devices and network towers. That forced a lot of innovation (including tools like better DNS64 and "happy eyeballs" protocols) and network stack hardening.
The roll out of out CGNAT in some cases is "let's drop IPv4 traffic randomly" and "happy eyeballs" in consumer devices is transparently driving a lot of consumer traffic to IPv6.
This is why mobile and consumer devices are leading the pack on IPv6 adoption.
It's maybe not all of Google that next needs to say "we're going to stop accepting IPv4 traffic", it's maybe more specifically GCP (and AWS and Azure) that need to do that to drive the non-consumer IPv6 push we need. The next best thing would be for all the cloud providers to at least start raising IPv4 address prices until their clients start to feel them.
"Stripped of all the other baggage that came with it..."
But that baggage is a huge part of the problem. Almost nothing you know about IPv4 applies when you switch to IPv6, and most of us found that out the hard way when we tried to make the switch. Leaves a pretty bad taste in your mouth.
I mean this is just wrong. Routing and switching behave exactly the same in V6 vs V4. Details on how you get an IP and what it looks like changed but there's TONS of knowledge shared between the two.
I get so many Second System Syndrome vibes off of IPv6. Surely other people must be picking it up too.
Future proofing it by jumping straight to 128 bits instead of 64. 64 would have been fine. Even with a load factor of 1:1000 by assigning semantics to ranges of IP addresses, 64 bit addressing is still enough addresses for 10 million devices per person.
If we become a galactic empire, we will have to replace the Web anyway because every interaction will have to be a standalone app or edge networking that doesn’t need to hear back from the central office for minutes, hours, days anyway. We could NAT every planet and go on forever.
The point is not really to support a galactic empire, the idea is that you have a network part and an interface part, each is 64 bits. The "network" part is used by routers, the interface part is to identify the device on the endpoint. Each interface have an identifier that is world unique (usually based on the MAC address), each network is also unique. Usually, your ISP gives you a /48 prefix, so you have 16 bits for potentially 64k internal networks. This way, you don't need something like DHCP to get an address, you just take it and you won't have conflicts.
But because you have two independent unique parts, you need twice as many bits, so 64+64=128 bits. It simplifies routing and address allocation, at the cost of 16 bytes per packet compared to 64 bit addresses.
That we could use IPv6 on galactic empires is an added bonus, but not really the reason.
Anti nat advocates seem to fall into the “the network shouldnt provide a stateful firewall” camp, because once you have a stateful firewall then nat is a trivial amount of extra bytes and very few issues with modern protocols (ones which don’t embed layer 3 addressing in layer 6/7 messages)
It's a big privacy problem too. Basing your IP address on your Mac address doesn't help in that regard either. Times have changed a lot since IPv6 was invented.
> Future proofing it by jumping straight to 128 bits instead of 64. 64 would have been fine. Even with a load factor of 1:1000 by assigning semantics to ranges of IP addresses, 64 bit addressing is still enough addresses for 10 million devices per person.
128 bit is like the least of adoption issues and basically meaningless difference vs 64.
But it shows weird priorities when they decided 128 then immediately wasted half of it on host part just to achieve "globally unique" host part that isn't really all that useful characteristic of the protocol.
> to achieve "globally unique" host part that isn't really all that useful characteristic of the protocol.
That's the essential part of self-configured addresses in IPv6 that does away with DHCP in most cases. DHCP is a stateful system that has to track every device's addresses individually. You don't need that with IPv6 thanks to this.
Disagree. APINIC got screwed on the IP allocation side, they're the RIR with the largest population but they have a tiny amount of IPs compared to ARIN. India and China have billions of people and not enough v4 space for them. If we go back and reallocate legacy blocks maybe you could make the system work but that would be a big fight with the legacy networks.
v6 restores the end-to-end principle and reduces network complexity once you go v6 only. Not more NAT traversal problems, no need to deal with STUN/TURN, small networks get even simpler with no need for a statefull DHCP server.
Sticking with only v4 space also artificially increases the cost of starting new networks and services because you have to buy space from the entrench IP save owners (unless we change the rules are start charging fees to legacy networks and reclaiming unused or poorly utilized space). Those higher barriers to entry hurt innovation and competition.
So v6 solves several technical and policies issues with the Internet, and maybe that's why we haven't seen speedy adoption. Because people have networks that exist today, some have paid a lot of money for IPv4 space and they want to make the most of that investment.
They don't really have an incentive to implement V6 unless things start to break without it.
I don't think v6 has been a failure half of all internet traffic runs on it! It powers the major cell phone networks, and large tech companies like meta have even gone v6 only in their data centers.
Don't think the problem is 64 vs 128. I don't think the problem is end users either, the vast majority of which don't even know what the IP protocol is in the first place (nor should they). The fault I think is on ISPs.
I use hyperoptic in the UK, if you replace the original router (which reserves the external 443 port for itself, i.e. no one sophisticated would keep it), there seems to be no way to get a v6 address. This is pure incompetence and carelessness. Like ISPs allowing their network to send packets spoofing IPs from outside their network. Add to that foreign ISPs (which means that even if your own network supports v6, you need v4 support when you are on holidays/travelling), and you have a situation where v4 cannot simply be switched off.
So for a website, what is the point of supporting v6 if v4 is never going away?
It's understandable that IPv6 would be ambitious rather than incremental given the cost of rolling out a new protocol; the bells-and-whistles IPv6 design is probably just a relatively small constant factor more expensive than the simplest possible address space expansion. Viewed that way, you only get the one chance to update the protocol, you might as well fix whatever you can.
well, its not without issues. the actual motivation was not that dhcp is the suxxors, but to promote a model where the assigned prefix was free and highly dynamic.
the goal being to support a model where one could support multiple prefixes to handle the common case of multiple internet connections. more importantly to allow providers to shuffle the address space around without having to coordinate with the end organization. this was perceived to be necessary to prevent the v6 address space from accruing segmentation.
> Future proofing it by jumping straight to 128 bits instead of 64.
It's hard to disagree with your point since 64 would definitely have been better than the 32 we have. I'm not convinced the choice of going for 128 bits posed any real challenge to adoption though.
The irony that I forgot to voice is that if we had gone 64 and feeder features we’d be farther along in adoption now and probably be consuming the address space at least a fraction as fast as people feared.
By raising the barrier to entry so high we guaranteed the features would likely never be needed.
I've been native IPv6 at home for a few years now. That worked flawlessly until a recent Windows 11 update somehow broke IPv6 in ways that I don't entirely understand. All the other Linux and Apple and et cetera things in my house are fine, but the Win11 laptop just refuses to handle certain IPv6 ranges (specifically including the address that the host interface for one of my web servers falls in). 100% contained within the Win11 device and TBH I can't be bothered to dig into it further so I just proxy through some other device that does work. (Guessing it'll get fixed a month/year/decade or so from now.)
I agree it's not a failure, but after 3 decades it's still frustratingly annoying to use at times.
Maybe not in the strict sense, but it kind of has.
In the enterprises I've worked in the past decade with IPv6 running, at least 75% of the Internet traffic is IPv6. In my discussions with other engineers managing large networks, they seem to be seeing more or less that same figure.
The problem is that virtually nobody knows IPv6. I regularly bring up IPv6 in engineers' circles and I'm often the only one who knows much about it. And so, I have doubts about it's long-term future, except for edge cases. I figure some clever scheme utilizing IPv4 and probably NAT will come around at some point.
IPv4s are about to be bought, held, portfoilo'ed, speculated, and rented/mortgaged/sold like real estate. Companies like IPXO are already doing it. The costs of public IPv4's are going to go up for no technical reason because a new distinct ownership layer is springing up between you and the ISP. You're going to start renting them or paying a holder for the right to use them (on top of your ISP to transport it) at some point. And you can continue to do that, or get IPv6's for free.
Just to be pedantic, it's "illegal" to hoard IPv4 or to buy it for any purpose other than using it directly. But yeah, in the real world it may become more financialized than it already is. OTOH if prices keep dropping maybe they won't bother.
Relatedly, I've been seeing some people buying up old domains and squatting on them with AI generated content. Not even ads, but content that seems like something that might actually show up in a rare Google search query. Not really sure what the play is or why this is better than advertising the domain for sale (do registrars punish overt squatting these days?).
We own our own IPv4 and IPv6 ranges, which is nice. There already is a holder for the US: ARIN.net and I hear it's a pretty spendy annual fee for most orgs (we're legacy. we've had ours for decades)
Yeah. If you're not an ISP or other LIR yourself, the correct path is to ask your ISP or a third-party ISP for a provider-independent allocation. This costs a nominal fee, about $50 per year.
I only know anything about RIPE policies but I gather the PI address processes and fees are very similar between RIPE and ARIN. RIPE has many members that are willing to handle address allocations for the RIPE fee plus 20% (so 60€ per year) and without bundling any other services.
In the end you're still just asking for a block, you don't pay for it. There are requirements which vary from RIR to RIR, sure, but there were requirements for requesting blocks in IPv4 as well originally.
Ultimately, as a regular person requesting IPv6 space you'd just ask your ISP, which can get practically as much as they want for free by submitting these kinds of requests. Meanwhile, for IPv4 space they're going to have a harder and harder time getting you additional space and chances are be unwilling to give it free/cheap.
> as a regular person requesting IPv6 space you'd just ask your ISP
In real life these requests don't lead to IPv6 allocation, no matter how they're asked or how often. Here are a few of the responses I've received just this year.
"At this time we are not able to provide a IPv6 unfortunately."
"We regret to inform you that, at this time, we do not offer IPv6 support."
"I wanted to inform you that IPv6 is currently not available"
My current ISP went as far as dumping their own IPv6 allocation. Three weeks ago it stopped being advertised in their ASN. Which I suppose is their way of telling me to stop asking.
Past that: Over 15yrs of asking various ISPs (large and small) to make allocations available, none of us ever budged the IPv6 needle.
It's already possible to "split" a frontend HTTP server on a given IP and port to arbitrary backend IPs and ports via the Host header and reverse proxies.
IPv6 and CGNAT growth has finally started to suppress IPv4 prices. There was a huge pump when hyperscalers decided they needed more. But IPv6 keeps growing and is the majority of traffic in many networks. If you own significantly more IPv4 addresses today than you need, I would dump them on the market yesterday. Spend some of the profits to move to IPv6 if still needed.
> Maybe not in the strict sense, but it kind of has.
I challenge you to find:
1. A hotel in the US that provides IPv6. I have NEVER been in one, and I once stayed in a hotel (in Mountain View, CA) that was giving out public IPv4 addresses.
2. An easier task: a SIP provider that has IPv6 (in the US). You know, for the VoIP that is supposed to be a poster child of end-to-end connectivity.
> In the enterprises I've worked in the past decade with IPv6 running
What about those without IPv6 running?
Anyway, in the enterprises I've worked in the past decade - of course, another anecdote - not once has anyone ever specified an IPv6 address of anything. Inside the organization or outside of it.
> not once has anyone ever specified an IPv6 address of anything. Inside the organization or outside of it.
If you deploy IPv6 correctly, you shouldn't have to disclose IPv6 addresses to users inside or out -- DNS keeps the address literals abstract, hidden from users.
The problem with private address ranges is that everyone thinks they're available. In a large enough enterprise you're bound to have conflicts. They usually pop up at the most inconvenient time and suddenly you're cosplaying ARIN in your IT department.
Unless you get to big. Or you merge with another company and have to combine your internal networks and oops, all the subnets are overlapping. Or you need to serve mobile clients who get better connectivity over v6.
The best one is async routing. You have a NAT, they have a NAT, you VPN together and think you have different IP address ranges, but unknown to the operator there's a little internal network with an overlap at the end of some slow line that is now getting flooded with internal traffic that's trying to go to a completely different network.
Pretty much every fortune 500 company does, which counts for millions of people on their networks every day. The troubleshooting calls for VPN routing vs internal LAN routing are fun endeavors of who is actually willing to take responsibility for things they don't understand.
if both you and companies you have site to site vpn with have IPv6 there is no IP conflict or NAT to worry about.... and that's about end of the advantages
Ok then: most people in the US do. The rest of the world is looking increasingly ipv6 too: https://www.google.com/intl/en/ipv6/statistics.html#tab=per-...
India is 71% IPv6 (probably thanks to Jio), China has it in its 5 year plan, Europe is doing well, etc
Is that worldwide adoption or adoption in the US? China went from almost nothing to 77% adoption is just a few years because they included it in their last 5-year-plan. How much of that adoption would be explained by China alone
I'd assume a lot of this is because of mobile devices of some type. Getting legacy network operators like cable providers to supply IPv6 has been hell.
Eyeball networks and cloud providers have been implementing IPv6. In the US all major phone carriers are v6 only with XLAT, the large residential ISP all have implemented v6 (Charter/Spectrum, Comcast/Xfinity, altice/optimum). The lagging networks are smaller residential ISP and enterprise networks.
In Asia they've implemented v6 everywhere pretty much because their v4 allocation is woefully insufficient. APNIC has like 4 billion people in it but less IP space than ARIN, with a population of less than 500 million.
Next year that chart will finally cross 50%. It was a mere 30% in 2030. Developing country mobile phone networks will continue to push it higher.
All we need to do is start having rich governments mandate IPv6, and also mandate IPv4 downtime as a punishment for those that don't comply / chaos engineering for the system as a whole. Then we can quickly finish the job.
I was in college when v6 was going through the RFC process. In my networking class we had to learn Netware (IPX) and v6, which have both turned out to be equally irrelevant, for different reasons. At this stage, I fully expect to retire having never deployed a single resource using v6.
I was expecting Google's IPv6 availability monitor[1] to show a crossover to a (slim) majority of their users accessing their services over IPv6 sometime soon, though it's sort of fascinating how close it gets to 50% recently without ever actually crossing over:
I remember 10+ years ago we were going to run out of IPv4 addresses and it was the next Y2K unless you adopted IPv6. I was able to get IPv6 for my servers and home, and I thought I was safe!
> "In fact, IPv4's continued viability is largely because IPv6 absorbed that growth pressure elsewhere – particularly in mobile, broadband, and cloud environments," he added. "In that sense, IPv6 succeeded where it was needed most, and must be regarded as a success."
Apparently it turns out IPv6 wasn't for me any way!
Yesterday I was required to turn on IPv6 on my router, while setting up some IoT things using Matter over Thread. Apparently that protocol uses IPv6 and doesn't work if your router is only routing IPv4.
There is a rich history of IoT devices using IPv6 to communicate among themselves without relying on the cloud. I think Nest started this trend. One Nest device sends a specific RA to make itself the router of all other Nest devices. All other devices can configure themselves thanks to SLAAC. The benefit of v6 is that there are so many addresses out there that the Nest device can just pick an arbitrary ULA and there won’t be collisions.
Don’t know about Matter though. If it requires the user to turn on IPv6 then it’s a user experience downgrade. It should just use IPv6 internally as an implementation detail.
That's incorrect. Matter-over-Thread absolutely does NOT require IPv6 on your router. Even Matter-over-WiFi will happily work in IPv4-only networks, as long as your router does not filter the IPv6 announcements.
Some routers can work as _relays_ between the Thread network and WiFi, but this is entirely optional.
I'm genuinely wondering if western governments (UK) will start issuing ipv6 addresses out to citizens as their digital id so they can track them online and offline.
Only half joking, some UK MPs might actually consider this a reasonable thing considering how many ipv6s there are.
Since ipv6 is just a 128-address, you could say any unique national ID is already an assigned ipv6. Heck, if you assign your services a UUID, you have also already assigned them an ipv6.
What makes an ipv6 useful is that you can route to it. Since you will never be connected to the network. The network will never be able to route packets to you, making the whole thing a little pointless.
We're not routable yet. Fairly certain people are trying to create computer/brain interfaces...
I'm thinking the gov issuing you an ipv6 address that you must use to connect to the internet. But it's also you're id too, since nearly all services are either online or getting pushed that way.
IPv6 has already won on mobile and been gaining fast traction in IoT space with Matter. The reason IPv4 is still around everywhere else is because we came up with ingeniuous techniques that squeezed the heck out of IPv4 address space. Also, IPv4 addresses are easier to type. That's pretty much it.
Yes, they are easier to type, and to remember, and it turns out, that's actually a big deal! When you are troubleshooting network problems, it's really nice to take everything but simple raw addresses out of the picture. It's really nice to be able to look at am address and instantly recognize if it's on the same (V)LAN as you are expecting, if it's unique, if it changed from what it was last time you checked, if it's an address for a VPN interface, if the packet you are sniffing is for this host or that host, if DNS is resolving correctly, etc., etc.
That’s why my home network is IPv6 only. NAT64 and DNS64 and 464XLAT work very well, and you only need to configure IPv4 once: in your router, where you need special configuration anyways.
>It was doomed the moment you had to maintain two separate stacks
Pray, tell me, how are we supposed to extend IPv4 with another {insert a number here} bits without creating a new protocol (that neccessitates running two stacks)?
Suppose that you have an old computer that understands only 32 bit addresses -- good ol' IPv4. Let's name it 192.168.10.10.
It then receives a packet from another computer with hypothetical "IPv4+" support, 172.12.10.98.12.4.24.31... ...Wait a minute, it can't, because your old computer understands only 32 bit addresses!
What if we really forced it to receive the packet anyway? It will see that the packet is from 172.12.10.98, because once again, it understands 32 bit addresses only.
It then sends back the reply to... you guessed it, 172.12.10.98. Not 172.12.10.98.12.4.24.31.
Yeah,172.12.10.98.12.4.24.31 will never get its reply back.
Do you see why any "IPv4 with extra octets" proposal are doomed to begin with now?
It wouldn't be able to receive it. That simple. Which is not a problem, any server would still have an old ipv4 address (172.12.10.98 from your example), like they currently do and probably will for decades.
My ISP refuses to give you a static IPv6 prefix unless you're a business customer, despite having an "unlimited" amount of them. This results in me not bothering to set it up properly and focusing on IPv4 still.
For those in the UK who want a static IPv4 or IPv6 block AAISP offer a L2TP service for £2/month. It's limited to 3 megabit/s but might be enough for some use cases.
My ISP is xfinity. They say the same thing but my IPv6 address hasn't changed any more frequently than my IPv4. In my experience it changing isn't any more annoying than my v4 changing so I'm not sure why people still get up in arms about it.
My xfinity ipv4 changes once every few years, if that. I treat it as static and update things if or when it changes, which fortunately isn’t too much work. I never requested anything special regarding it, and I have a normal/non-business account. I wonder why some change often and others don’t?
I had Xfinity for 4 years and my IP changed once in that time! Now I have fiber from centurylink, and it changes anytime I need to reboot the fiber modem or my firewall. Different companies, same metro area though. That too makes me wonder about how both manage their allocations give the difference in IP assignments.
On the other end of the connection, there are physical servers and routers. Every once in a while they change how things are connected/deployed for maintenance, upgrades, etc.
Pretty much, I have my cable modem on continuous power and it will keep the same address pretty much forever. Two times it changed is when I had a 48 hour power outage and shut everything down, and the other time was maintenance at the cable companies side where they rebooted their equipment.
Get a virtual server and do the things on it that you'd want a static address for. Use a VPN connection back to your home to merge it with your network. This is a great way to deal with CGNAT.
I don't have a static IPv4 address and I have to use a DDNS built into the Caddy plugin on my OPNSense router. From what I understand, you can't get a static "local" (I know, IPv6 has no direct equivalent) address to use for a reverse proxy — at least not in an easy manner. I might be completely wrong but that's why I don't bother with IPv6.
Yep. ULA addresses are the equivalent of 10.0.0.0/8, 192.168.0.0/24, and 172.16.0.0/12 space. [0] And you can use them to do NAT, just like with IPv4.
The huge difference from the IPv4 world is that the procedure for generating your /48 ULA prefix ensures that it's very, very unlikely that you will get the same prefix as anyone else. So, if everyone follows the procedure, pretty much noone has to worry about colliding with anyone else's network.
Following the procedure has benefits. For example, VPN providers who want to use IPv6 NAT can do that without interfering with the LAN addressing of the host they're deployed to... companies that merge their networking infrastructure together can spend far less (or even zero) time on internal network renumbering... [1] etc, etc, etc.
[0] And link-local addresses are the equivalent of 169.254.0.0/16 space.
[1] Seriously, like a year after one BigCo merger I was subject to, IT had still not fully merged together the two company's networks, and was still in the process of relocating or decommissioning internal systems in order to deal with IPv4 address space constraints. Had they both used ULA everywhere it was possible to do so, they could have immediately gotten into the infosec compliance and cost-cutting part of the network merging, rather than still being mired in the technical and political headaches forced upon them by grossly insufficient address space.
Note that although the policy is that you choose a random prefix, nothing actually enforces this and nothing stops you using fd00::1, fd00::2, etc just like 10.0.0.1 etc.
I recently moved house and looked at a new offer from a new ISP for a long term lockin but a cheap price. They used CG-NAT. I instead chose one which gives me as many ipv4s or ipv6s as I can reasonably use, doesn't oversubscribe its upsteam connectivity etc.
For home internet service I would prefer to pay extra for a better service, it's too important to try to penny-pinch 0.1% of my income on it.
But then I live in a capitalist country where there's competition, I believe some countries you don't get a choice.
FYI it's practically impossible not to oversubscribe your upstream connectivity unless they either spend way too much money or offer very slow service to users. Consider ten thousand users with 1G connections - should they have 10 terabit upstream?
The more practical thing to look for is that they aim to upgrade it based on need, instead of arbitrarily throttling the users.
Where I live the cable system is fine, and the cellular system is fine... until one goes down, then the other gets flooded with traffic and stops working leaving no internet at all.
Not really. DJB’s clearly a very, very smart person, but he missed the mark on almost all of that. The problems he described which are real have been satisfactorily solved; they weren’t intractable. The rest turned out to be non-issues.
IPv6 continues to rumble along, gaining market share, because China. Increasing IPv6 adoption was in the 14th Five Year Plan, and about 75% of mobile in China is now IPv6.
I started looking at self-hosting many applications at home once I realized that IPv6 could enable me to do that securely without any complicated router/firewall configuration that would need to be maintained.
The only wrinkle I ran into is that apparently ISPs are still reluctant to give out static IPv6 prefixes to residential customers. So you still need some kind of DDNS setup, which is lame.
and it never will, because IPv4 has become a defacto reputation system for the exact same reason that IPv6 was created: a limited supply. It wouldn't surprise me to see the continued balkanization of the internet that there is a particular underclass of exclusively IPv6 traffic, but its not going to take over everything because once decentralized systems are now in the hands of a few decisionmakers in the case of, say, email.
Dynamic DNS, DHCP, and static assignment are all still part of IPv6. Putting single IPs in switch ACLs is an anti pattern. Consider zero trust or working with whole subnets(they're plentiful in v6) instead.
I have noticed that on my last Windows computer (Windows 10) and my current computer (Windows 11) IPv6 works great for a little while after a reboot, but then just seems to die. I have my house and all internal automation configured for IPv6 first and its great on all my Linux computers and phones.
I love IPv6 but organizations seem to struggle with it. My ISP, for example, had issues routing it after a backend update so they decided to just turn it off. I'm now stuck on CGNAT IPv4 which results in constant captchas :/
Meanwhile, there is a whole grey market built around this. People sell “CGNAT mobile proxies” that ride on carrier and ISP NAT, and the whole point is that they are a pain to block without nuking huge ISP ranges. So they get marketed as a convenient way to dodge shadowbans, spam filters, and basically any abuse defense that relies on IP reputation.
It would be nice if we had a blackout CGNAT day where a bunch of major sites don't serve traffic to people behind CGNAT to give the ISPs a bit of a scare.
It kind of has. The majority of internet traffic is IPv6. The three biggest internet hub regions (USA, Europe, China) have IPv6 mandates. Most apps support IPv6. Google and Apple force them to, od they get kicked off the app store. Almost all mobile networks (which means almost all end devices) are IPv6-only, with slow inefficient tunneling for IPv4. The price of IPv4 addresses is declining.
At what point will we be allowed to say IPv6 hasn't failed? When the IPv4 internet finally switches off for good? It feels like no achievement is high enough for those who don't like IPv6 to change their minds. I would've thought making up 50% of internet traffic and 50% of end devices being on IPv6-only networks would be good Schelling points, but evidently they're not!
> At what point will we be allowed to say IPv6 hasn't failed?
"IPv6 ... still hasn't taken over the world [after thirty years of deployment]." is a very different statement than "IPv6 has failed.".
Noone who has successfully extracted their head from their ass says that IPv6 has failed. It's widely deployed on the Internet, and on who knows how many corporate intranets and SOHO/home LANs.
IMO, it's stupid to ever consider turning off IPv4. There surely exist useful systems out there that will never be updated to work with IPv6.
I see IPv6 as an "IPv4 address pressure relief system". In the future, SOHO/home LANs can run servers on IPv6, datacenters can run servers mostly on IPv6 but also v4 if they really want, and SOHO/home networks can be behind an IPv4 CGN because all of their unsolicited inbound traffic will come over IPv6.
>IPv6 ... still hasn't taken over the world [after thirty years of deployment]." is a very different statement than "IPv6 has failed.".
It's incredibly likely that the GP was referring to comments in this thread, which were indeed claiming that IPv6 has failed, despite the fact that its deployment has been steadily climbing up worldwide.
By the way...
>In the future, SOHO/home LANs can run servers on IPv6
The future is now. My web server is IPv6 only precisely due to the same reason you mentioned: my ISP has put me under a CGNAT. People can still connect to my website through the Cloudflare reverse proxy though (which I have only enabled for IPv4, IPv6 users get to enjoy direct connection).
IPv6 addresses are ugly and hard to memorize. IPv4 addresses are pretty and easier to memorize. That's about the end of the discussion as to why it's basically a failure.
Contrary to some other comments: no, IPV6 hasn't taken over the world at all.
In my case, I administrate a small server at home, where I self host many services that are made available to myself, friends and families, over the internet.
In that context, IPv6, is SADLY (please note that I have NOTHING against IPv6), a limitation, even a nightmare to use.
Some programs do not handle IPv6 at all. Game servers for instance, do not support it, the one that I think about is: Arma 3. But there are many others
In 2025 (and 2026 too?), 4G (5G?) operators do not all route over IPv6 -> which means that if your domain only has a AAAA record, some people using 4G will not be able to access ANY of your services. This issue forced me to beg my ISP to obtain an IPv4 "fullstack" as they call it.
Without that IPv4 you have to go through some kind of tunneling (like Cloudflare) -> and guess what? Cloudflare sometimes crashes (it happened super recently remember?) and in that situation -> ALL your services accessible through the tunnel are "down" for your users. Plus, it is EXTREMELY unsatisfying to rely on an external private-owned service for a selfhosting project.
In almost ALL context IPv6 is seen as optional, additional, additional configuration and is NEVER the default. NEVER. Which means: more configuration, possibly more struggle.
>ALL your services accessible through the tunnel are "down" for your users
Not all.
I operate site with IPv6 only origins behind cloudflare.
During the outage I manged to login to the dashboard after some time and remove cloudflare for nearly 2 hours, and traffic level stayed close to 50% during the IPv6 only period.
Nobody complained: those who did not have working IPv6 probably blamed it on cloudflare.
> traffic level stayed close to 50% during the IPv6 only period.
> Nobody complained: those who did not have working IPv6 probably blamed it on cloudflare.
You described a situation where the outage resulted in 50% of your customers were unable to reach you and you were unable to do anything about it. I don’t think this story is a win for IPv6, regardless of whether your customers blame CloudFlare or not.
idk if arma3 does server discovery, but in case of manual ip input there some kind of OS-networking-level adapter should help. Usecase seems too obvious for something like that not to exist
Most 4G networks are actually IPv6-only, with IPv4 traffic being routed through inefficient tunnel systems. This is why Apple and Google require all mobile apps to use IPv6.
I have fiber to my house and no native IPv6 support. I did some research and it seems there is a way to enable IPv6, but it’s janky and just tunnels over IPv4 so what’s the point?
I would love for IPv6 to actually take off but somehow it feels like we are still a decade away from ubiquitous adoption.
> In almost ALL context IPv6 is seen as optional, additional, additional configuration and is NEVER the default.
Weird. The past two ISPs I've had (Comcast and Monkeybrains) both had IPv6 enabled by default. I've looked at a bunch of SOHO networking gear and IPv6 is on by default. On every Linux and Windows system I've touched in the past ten, fifteen years you have to go significantly out of your way to disable IPv6.
> Some programs do not handle IPv6 at all. Game servers for instance, do not support it...
Depends on the game server. Many I run absolutely do.
Your complaints smell like you tried to run an IPv6-only client network, which would be an absolute nightmare. That's just a stupid thing for a SOHO network (and the networks that serve most corporate client hosts) to do. IPv4-only Internet hosts exist, so it's a no-brainer to provide IPv4 connectivity to clients.
On the other hand, running IPv6-only infrastructure networks can make a ton of sense. One very large such operator is Comcast, a US ISP.
IPv6-only is the future for mobile phones, and mobile devices are the future of the internet.
And it is consumer devices (and IoT devices) which are the most numerous and also the most price sensitive, and this is where IPv4 is disappearing first.
It's reaching around 50% adoption according to Google stats? Steady growth, though still annoyingly slow. It will need a few more decades at this rate.
> "IPv6 wasn't about turning IPv4 off, but about ensuring the internet could continue to grow without breaking,"
Then it's failure is by design. I should not want to multiplex/bridge different versions of the network-layer protocol; and certainly not to avoid using the new protocol because the old one seems more usable and approachable.
My "conspiracy theory" is IPv6's point to point connectivity is inconvenient to anyone except end users. And, rent-seekers can't extract money if the ranges aren't limited. American mind can't comprehend not rent-seeking any new invention.
IPv4 "works" and ISPs are incredibly resistant to changing things that "work".
Because support is needed basically end to end, it's going to take an ungodly amount of time for ISPs to figure this stuff out.
It's pretty frustrating having all my hardware support v6 with the only barrier being my ISP who refuses to support it in my location (they support it in other locations).
This is mainly due to mobile devices only being issued ipv6 addresses by the telco 4g networks. They are the only ones using ipv6 on the millions of clients scale.
Everything supports both. We are talking about being issued only IPv6 addresses where you actually use it to connect to stuff.
Most mobile devices are only issued an IPv6 address and therefore when the masses do google searches it uses IPv6 and makes it look like there is huge adoption.
Unsurprisingly Google actually does also have IPv4 addresses. What they're measuring isn't "How did you reach our servers?" but instead "Could you have reached our IPv6 servers?"
> We are talking about being issued only IPv6 addresses where you actually use it to connect to stuff.
You seem to be asserting that dual-stack machines use IPv4 by default, but that's not really true. If your machine has both IPv4 and IPv6 connectivity, browsers will in fact use IPv6 to connect to sites that support it, like Google. They prefer IPv6 by default and fall back to IPv4 if IPv6 is slower (Happy Eyeballs algorithm).
Of course, random software can mostly use whichever it wants, so I'm not claiming every process on such a machine will use IPv6, but most common stuff does.
Still disabled on all my networks and will be forever. Incoming HN downvotes because I'm not using the coolest latest technology.
ipv4 accidentally provides "casual anonymity" and "one ip does not identify device", which is incredibly important in this age of overbearing surveillance by government and private companies. ipv6, even with the "privacy extensions", is one subpoena away form directly identifying your individual device. ("ISP X: who did you assign this block of ips to on Y date?")
ipv4 has a boatload of issues (the worst of it is probably the unused and 'dangerous' flags), and ipv6 offers a boatload of cool features (The most beautiful is probably the flow state tracking).
However ipv6 was designed in a naive vacuum where no one possibly imagined the internet being abused to destroy an individual's inherit right to anonymity.
Oddly enough, the people most hellbent on spying on you: Facebook, Google, etc are the ones screaming for ipv6 the loudest.
It’s ok to understand something and disagree with it. It’s another to proudly wear ignorance on one’s sleeve. That’s never a good look.
There’s no way in which IPv6 is less private than IPv4. An ISP issues your house an IPv4 address and an IPv6 /48 network. Both of those can be subpoenaed equally. The privacy extensions work as advertised.
And in reality land, the big companies are the ones pushing for the upgrade because they’re the ones hardest hit by IPv4’s inherent limitations and increasing costs. Same rando in Tampa isn’t leading the charge because it doesn’t affect them much either way.
> There’s no way in which IPv6 is less private than IPv4
With IPv4 behind CGNAT you share an address with hundreds of other users. This won't protect you against a targeted subpoena, but tracking companies typically don't have this kind of power, so they have to resort to other fingerprinting options.
On the other hand, an IPv6 address is effectively a unique, and somewhat persistent, tracking ID, 48/56/64-bit long (ISP dependent), concatenated with some random garbage. And of course every advertiser, every tracking company and their dog know which part is random garbage; you are not going to fool anyone by rotating it with privacy extensions.
CGNAT is nowhere near the common case yet. And frankly, I’m horrified that anyone’s describing it as a good thing. CGNAT is the devil, even if it accidentally has one not-terrible feature, and especially when ISPs realize that they can sell those NAT logs to companies who still want to track end users.
For tracking purposes, an IPv6 address is 48 bits long. That’s what identifies a customer premise router, exactly like a IPv4 /32 identifies one. The remaining 80 random bits might as well be treated like longer source port numbers: they identify one particular connection but aren’t persistent and can’t map back to a particular device behind that router afterward.
>CGNAT is nowhere near the common case yet. And frankly, I’m horrified that anyone’s describing it as a good thing.
For some reason, "CGNAT == privacy" is a very common sentiment on Hacker News. Yeah, Hacker News. It's bewildering, and after my last comment [0] talking about it, I have kinda already given up trying to convince people that CGNAT is devilish and not at all a privacy protector.
Perhaps this is the difference, some people are concerned with being anonymous from companies like google, amazon, etc. Some don't mind that, as long as they are anonymous from a government.
Your mention of subpoena suggests you don't care about google tracking you.
I was directly replying to someone saying they could subpoena the temporal owner of an IPv6 address, as though that were somehow different than IPv4.
The tracking is a moot point. You can be tracked using the same technologies whether you connect though v4 or v6, and neither stack has the advantage there.
Unless my understanding of how IPv6 is flawed, I don’t think your assertion is true in practice. One of the big benefits to IPv6 is that addresses are plentiful and fairly disposable. Getting a /48 block and configuring a router to assign from the block is pretty straightforward.
I’m aka unsure if IPv4 really gets you the privacy advantages you think it does. Your IP address is a data point, but the contents of your TCP/HTTP traffic, your browser JS runtime, and your ISP are typically the more reliable ways to identify you individually.
You can nat all your ipv6 traffic behind a single IP if you want. Or a new IP for every connection.
Realistically though there's enough fingerprinting in browsers to track you regardless of your public IP and whether it's shared between every device in the house or if you dole out a routable ipv4 to every device.
CG-NAT gives more privacy benefits as you have more devices behind the same IP, but the other means of tracking still tend to work.
For me I just don't see the appeal of supporting both ipv4 and ipv6. It means a larger attack surface. Every year or two I move onto my ipv6 vlan and last a few hours before something doesn't work. I still don't see any benefit to me, the user.
> Realistically though there's enough fingerprinting in browsers to track you regardless of your public IP and whether it's shared between every device in the house or if you dole out a routable ipv4 to every device.
Yes, browser fingerprinting is a big issue, but it can be mitigated. The first thing everyone should do is to use a network-wide DNS blacklist against all known trackers (e.g. https://github.com/hagezi/dns-blocklists) and run uBlock Origin in the browser.
You can go further and restrict third party scripts in uBlock, or even all scripts. This will break at lot of websites, but it is a surefire way to prevent fingerprinting.
IPv6 itself seems to provide a larger attack surface based on IPv6-specific CVEs. I don’t know if it’s the added complexity or that it’s treated as a second class citizen by devs, but I still see a solid number of these coming across the CVE feed.
When something happens over IPv4 people treat it like "the Internet has malicious actors, water is wet", but when it happens over IPv6 it must be IPv6's fault.
> Realistically though there's enough fingerprinting in browsers to track you regardless...
Yep. For the OP, IPv6 "Privacy" addresses do what he's looking for. You can change how long they're valid for on Linux, so you can churn through them very frequently if you wish.
> Every year or two I move onto my ipv6 vlan and last a few hours before something doesn't work.
Odd. I've been using IPv6 for like fifteen, twenty years now with no trouble at all. If you've been using a "single stack" IPv6-only network, well, there's your problem.
> For me I just don't see the appeal of supporting both ipv4 and ipv6. It means a larger attack surface.
The attack surface with IPv6 is exactly as large as if each of your LAN hosts had a globally-routable IPv4 address. Thinking otherwise is as smart as thinking that the attack surface on a host increases linearly with the number of autoconfigured IPv6 addresses assigned to that host from the same subnet.
If you don't want the IPv6 hosts on your LAN to be reachable by unsolicited traffic, set the default policy for your router's ip6tables FORWARD chain to DROP, and ACCEPT forwarded packets for ESTABLISHED or RELATED connections. If you're not using ip6tables, do whatever is the equivalent in the firewall software you're using. If you know that you have rules in your FORWARD chain that this change would break, then you already knew that you could simply drop unsolicited traffic in the FORWARD chain.
Unrelated to that, I see no reason to get rid of IPv4.
I expect that the future will be that nearly all "residental" [0] and non-datacenter business connections provide globally-routable IPv6 service and provide IPv4 via CGNAT, as IPv6 will be used for servers deployed at these sorts of sites. [1] I expect that the future will be that all datacenters and "clouds" will provide globally-routable IPv6 to servers and VMs, and globally-routable IPv4 to the same by way of load balancers.
So, home servers [1] will use IPv6, datacenter and "cloud" servers will use IPv4 and IPv6, and "legacy" devices that work fine but will never have their IP software updated will use IPv4.
I see IPv6 as a "reduce the pressure on the IPv4 address pool" mechanism, rather than a "replace IPv4" system. Again, I see no reason to get rid of "short" IP addresses. Default to using "long" ones, and keep the "short" ones around just in case.
[0] I'm including people's personal mobile computers in this definition of "residential".
[1] "Servers" here include things like "listen" video game servers or short-lived servers for file transfers and stuff like that.
It's virtually always used with some firewall rules, so it sort of is? It's just dogma to insist that there are no security benefits to having a single choke point for traffic.
You can clearly see an initial steep spike to the curve where mobile adoption was new and fierce, and then the curve starts slowly becoming less steep over the last 10 years. It will peter out and remain steady when mobile device adoption reaches critical mass.
No, as I pointed out in another reply to you, home internet is commonly dual-stack (at least in the US and many other countries), and machines with dual-stack connectivity can and do use IPv6 to connect to sites that support it. You can verify this yourself using Wireshark or similar tools.
It's hard to adopt something that schools don't teach. I know someone who graduated from UCI with a CompSci degree with a specialization in networking, just before the COVID19 pandemic began. He recalled that the networking courses he took did not cover IPv6 at all, except to describe the address format (i.e. 128 bits, written as hexadecimal, colon-separated). Everything he learned about IPv6, he had to learn on his own or on the job. A standard that has been published for over two decades, heavily used for over a decade, and critical in the worldwide growth of the Internet, was treated as an afterthought by one of the premier universities in the US.
Obvious disclaimer: This is a sample size of 1, and an anecdote is not data, yada yada. I'm not involved in academia, and have no insight into the adoption of IPv6 in CompSci networking curricula on a broader level.
Tbh it’s is a huge PITA with little practical benefit. IPv6 is the Perl 6 of networking.
Many of the big benefits are things that don’t deliver anything that folks are lacking. You also need to understand how you fit in the overall universe more.
What about the benefit of there being enough addresses?
The widespread deployment of NAT and VPNs has counter acted the market forces that were assumed to make IPv6 appealing.
IPv4 addresses are still expensive. NAT is a value add for a lot of cloud platforms.
IPv6 has arguably done more to counteract market forces related to IPv4 address exhaustion.
I absolutely love the things that IPv6 delivers and employ it on purpose.
The world very clearly doesn’t revolve around what HN users “love”.
Meanwhile, I was taught and practiced IPv6 in 2003-5 in engineering school (France).
As of 2024, IPv6 deployment in France was >97% mobile and >98% residential due to not being required for obtaining a 5G radio license (and then v6 simply carried downward to being available on 4G) + every ISP that provides FTTH also providing v6.
https://www.arcep.fr/fileadmin/reprise/observatoire/ipv6/Arc...
Over here IPv6 JustWorks to the point of absolute boredom.
IPv6 was superceded by NAT a long time ago. It will die a slw and quiet death which is why it is now being ignored by training facilities and experts worldwide.
Digital Ocean didn’t even have an ipv6 address on by default in the droplet I created last week. It’s just a switch to flip, but I’ll bet the support costs of hobbyists/enthusiasts not realizing they needed to also write firewall rules, make sure ports weren’t open for databases and things like that for ipv6.
It's a "just doesn't work" experience every time that I try it and I don't experience any value from it, it's not like there isn't anything I can connect to on IPv6 that I can't connect to on IPv4.
My ISP has finally mastered providing me with reliable albeit slow DSL. Fiber would change my life, there just isn't any point in asking for IPv6.
Also note those bloated packets are death for many modern applications like VoIP.
Exactly. Spectrum delivers good IPv6 service in my area. I tried it when I upgraded my gateway. All of my devices are assigned 4 IPv6 IPs, hostnames are replaced by auto assigned stuff from the ISP, and lots of random things don’t work.
I went from being pumped to learn more to realizing I’m going to invest a lot of time and I could not identify and tangible benefit.
> those bloated packets are death for many modern applications like VoIP.
Huh? The packet sizes aren’t that much different and VOIP is hardly a taxing application at this point anyway. VOIP needs barely over dial-up level bandwidth.
My memory of IPv6 is getting waves of support tickets from people who took their (already questionable) practice of blocking ICMP on IPv4, blocked ICMPv6, and then got confused when IPv6 stopped working.
It was?
Isn’t it what all the cell phones networks use these days? And most ISP’s?
They may hand the end user device a IPv4 address but don’t they actually use IPv6?
Yes as I said in a sibling post the telcos are the only ones using it, and that is the only reason that graphs like the google client one exist. That is only because it already exists and is cheaper than using NAT when you have hundreds of millions of clients.
IPv6 only ISPs will never leave the mobile space.
“The largest ISPs are the only ones using it” is another way of describing it as ubiquitous.
I disagree. If they were the largest ISPs then adoption would already be over 50% instead of stalling below it.
I would say its more "Wireless only ISPs are the only ones using it"
> I would say its more "Wireless only ISPs are the only ones using it"
So… the largest ISPs.
Recent number show about 94% of Americans have cell phones and 92% of American households have Internet connections. In raw numbers, that’s about 300M cell phones and 111M households.
If zero fixed ISPs support IPv6, that’d still be about 75% of total Internet connections that do.
What are you even basing that on? Here are some facts:
- You have to pay money to get a static IPv4 address for cloud machines on eg AWS. Anything needing a static IPv4 will cost more and more as demand increases. NAT doesn’t exactly fix that.
- Mainstream IoT protocols have a hard dependency on IPv6 (eg Matter/Thread). Not to mention plenty of 5g deployments.
- Many modern networks quietly use IPv6 internally. I mean routing is simpler without NAT.
So it almost definitely won’t die. It’s more likely it’ll slowly and quietly continue growing behind the scenes, even if consumers are still seeing IPv4 on their home networks.
IPv4 addresses have been dropping in price for a few years and are cheaper in real terms than at my point in the last 15
Matter/Thread use private IPv6 addresses so it's just an implementation detail. Nobody is exposing light switches to the public Internet.
This is not even funny to read, given huge networks like T-Mobile USA being IPv6-only.
They are using IPv6 as a fancy transport protocol for IPv4 NAT.
By being IPv6-only they are effectively making their users to preferentially connect over native IPv6 though.
Personal anecdote, but once you have IPv6 setup properly (meaning your devices prefer IPv6 over IPv4) 70-80% of your internet traffic will be IPv6.
The NAT64 is really just there for the holdouts.
I run dual stack at home with dns64/nat64. I average 50/50 traffic v4/v6. Web browsing gets skewed v6 but large file transfers and some streaming pushed it back to 50/50 overall. My family would revolt if I went v6 only so I'm not sure I'd say its just there for holdouts. Major annoyances include any old device and my hue bridge.
No; most sites I reach from the phone seem to be reached via IPv6. E.g. hitting whatismyip.org exposes an IPv6 (though mentions an IPv4 because they're trying to discover that, too). Some sites do not support IPv6; for those indeed there's a XLAT464 service.
464XLAT is for dealing with IPv4 literal addresses in a v6 only network. Non-literals can be addressed with DNS64 & NAT64
https://www.google.com/intl/en/ipv6/statistics.html
People love this graph and regularly tout it as if it explains full internet usage. Especially when they dont bother to add any explanation or comment alongside it.
This graph is mainly due to the fact that telcos use IPv6 for mobile devices, nothing more. Over time you will see that graph flatline and peter out as mobile device uage reaches critical mass.
It was simply to point out that you are objectively incorrect. No commentary was necessary. My phone and home broadband both use IPv6 primarily.
In US even desktops have 45% adoption rate: https://radar.cloudflare.com/explorer?dataSet=http&groupBy=i...
afaik every single major US fixed line ISP is rolling out ipv6.
It seems more the other end of the stick: the IPv4 side of the graph is mainly held up due to corporations. The consumer internet continues to switch, but corporate VPNs are going to continue to drag down the numbers until corporations get charged enough for IPv4 address space that bottom lines start to notice.
Every major ISP in the US, India, and most of the rest of Asia that I’ve seen is handing out and using IPv6 now too.
Hell, chances are if you got a new router (like any new client) for your ISP, you’d be on v6 too.
Yep, and even with all those countries with their billions of mobile devices IPv6 use still hasnt even reached 50%.
Pretty much all ISPs hand out both IPv6 and IPv4 addresses to their clients, this is nothing new. When they start only issueing IPv6 IPs is when it would start truly taking off, but it will never get to that point and it will never happen.
It feels like you are constantly moving goal posts here. Your original statement was it will die a slow and quiet death. Are you now saying that this mobile use case will start to switch back to IPv4? It may not kill IPv4, like was initially planned, but it's not going away.
According to APNIC labs, IPv6 adoption in India is ~79% and in China it is ~53%.
Those are the only two countries that could plausibly have billions of mobile devices and they appear to have reached 50%.
India: https://stats.labs.apnic.net/ipv6/CN?c=IN&x=1&v=1&p=1&r=1&w=...
China: https://stats.labs.apnic.net/ipv6/CN?c=CN&x=1&v=1&p=1&r=1&w=...
Looks like it’s right at 50% and rapidly increasing.
[https://www.google.com/intl/en/ipv6/statistics.html]
What exactly are you going on about? 5-10 years for the old devices to be EOL’d, and we’ll likely be at 95%.
Devices maybe, software won't :-\ (We're going to see ever-diminishing pockets of IPv4 around for a loooong time, much like we still see pockets of Cobol.)
pick a lane?
>> I know someone who graduated from UCI with a CompSci degree with a specialization in networking, just before the COVID19 pandemic began. He recalled that the networking courses he took did not cover IPv6 at all...
I am not doubting you, but I feel this story is too hard to believe without adding further nuances...
MIT 6.829 teaches IPv6 since 2002: https://ocw.mit.edu/courses/6-829-computer-networks-fall-200...
In Portugal and other countries, there are subjects on Computer Science before College or University, and they teach it on High School...
The issue is that it’s not taught with IPv6 first. Networking courses do all kinds of stuff using IPv4 to demonstrate various protocols on top (e.g. http, tcp, icmp, etc).
Then there is usually a chapter on IPv6 that just briefly covers the differences.
I.e. the exercises all tend to use IPv4 as the foundation so people don’t practice v6
But TCP or HTTP don’t care about the underlying transport. They’re higher level protocols that are payloads to either IPv4 or IPv6. It’s irrelevant what the transport is when dissecting HTTP and very little time should be spent on it.
IPv4 is, for all intents and purposes, still the default transport. It’s also simpler than IPv6 in some regards. When teaching layer 3, it makes sense to teach both, and teach IPv4 first. Though I fully agree that they should be taught with equal emphasis. I don’t doubt there’s a good number of programs out there that don’t into sufficient detail on IPv6.
Well it makes sense, no one uses ipv6 anyhow. Most I know are waiting for ipv8.
I don't like to admit this, but at this point honestly I think ipv6 is largely a failure, and I say this as someone that wrote a blog post for APNIC on how to turn on ipv6.
I'll get endless pushback for this, but the reality is that adoption isn't at 100%, it very closely needs to be, and there are still entire ISPs that only assign ipv4, to say nothing of routers people are buying and installing that don't have ipv6 enabled out of the box.
A much better solution here would have been an incredibly conservative "written on a napkin" change to ipv4 to expand the number of available address space. It still would have been difficult to adopt, but it would have the benefit of being a simple change to a system everyone already understands and on top of a stack that largely already exists.
I'm not proposing to abandon ipv6, but at this point I'm really not sure how we proceed here. The status quo is maintaining two separate competing protocols forever, which was not the ultimate intention.
> A much better solution here would have been an incredibly conservative change to ipv4 to expand the number of available address space
"And what do you base this belief on?
Fact is you'd run into exactly the same problems as with IPv6. Sure, network-enabled software might be easier to rewrite to support 40-bit IPv4+, but any hardware-accelerated products (routers, switches, network cards, etc.) would still need replacement (just as with IPv6), and you'd still need everyone to be assigned unique IPv4+ addresses in order to communicate with each other (just as with IPv6)."[0]
0: https://news.ycombinator.com/item?id=37120422
> Fact is you'd run into exactly the same problems as with IPv6.
If you treat IPv4 addresses as a routable prefix (same as today), then the internet core routers don't change at all.
Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.
IPv6 seems to be a standard that suffered from re-design by committee. Lots of good ideas were incorporated, but it resulted in a stack that had only complicated backwards compatibility. It has taken the scale of mobile carriers to finally make IPv6 more appealing in some cases than IPv4+NAT, but I think we are still a long way from any ISP being able to disable IPv4 support.
> Only the edge equipment would need to be IPv4+ aware. And even that awareness could be quite gradual, since you would have NAT to fall back on when receiving an IPv4 classic packet at the network. It can even be customer deployed. Add an IPv4+ box on the network, assign it the DMZ address, and have it hand out public IPV4+ addresses and NAT them to the local IPv4 private subnet.
Congratulations, you’ve re-invented CGNAT, with none of the benefits, and the additional hassle of it being an entirely new protocol!
No. No “extra bits” on an IPv4 address would have ever worked. NAT itself is a bug. Suggesting that as an intentional design is disingenuous.
Hardware would catch up. And IPv4 would never go away. If you connect to 1.1.1.1 it would still be good ole IPv4. You would only have in addition the option to connect to 1.1.1.1.1.1.1.2 if the entire chain supports it. And if not, it could still be worked around through software with proxies and NAT.
So... just a less ambitious IPv6 that would still require dual-stack networking setups? The current adoption woes would've happened regardless, unless someone comes up with a genius idea that doesn't require any configuration/code changes.
Sort of. I think people would understand
201.20.188.24.6
And most of what they know about how it works clicks in their mind. It just has an extra octet.
I also think hardware would have been upgraded faster.
The main thing is keeping current addresses, not having both an ipv4 and ipv6 address.
Just like for an apartment you append something like 5B. And for a house you don't need that.
I disagree. The current adoption woes are exactly because IPv6 is so different from IPv4. Everyone who tries it out learns the hard way that most of what they know from IPv4 doesn't apply. A less ambitious IPv4 is exactly what we need in order to make any progress
It’s not _that_ different. Larger address space, more emphasis on multicast for some basic functions. If you understand those functions in IPv4, learning IPv6 is very straightforward. There’s some footguns once you get to enterprise scale deployments but that’s just as true of IPv4.
But that is a bug in history. IPv6 was standardized BEFORE NAT.
“most what they know from IPv6” is just NAT.
> A less ambitious IPv4 is exactly what we need in order to make any progress
but we’re already making very good progress with IPv6? Global traffic to Google is >50% IPv6 already.
The only solution is a gov't mandate. China went from almost no adoption to leading the world in adoption (77% of all Chinese internet users) in a few years because they explicitly prioritized it in their last 5-year-plan.
The ISPs aren't gonna do it on their own.
Circa 1999 I was working for Cisco as a sysadmin. I got my CCNP through internal training and considered making a career of network administration, but ipv6 changed my mind. It seemed so much more difficult and unpleasant to deal with. I didn't want that to be my day to day work.
I think the same thing happens on a different scale with ISPs. They don't want to deal with it until they have to for largely the same reason.
IPv6's failure was mostly caused by the IETF's ivory tower dwellers, who seem to generally have no practical experience or understanding whatsoever of how networks are actually built and run today, especially at the small to mid scale.
Small site multihoming, for example, is an absolute disaster. Good luck if you're trying to add a cellular backup to your residential DSL connection.
IETF says you should either have multiple routers advertising multiple provider-assigned prefixes (a manageability nightmare), or that you should run BGP with provider independent address space; have fun getting your residential ISP or cellular carrier onboard with this idea.
IETF has a history of being hostile to network operators. I mean actual network operators - not the people who show up at conferences or work the mailing list who just happen to get a paycheck from a company that runs a network (and have zero production access / not on call / not directly involved in running shit). It's gotten better in the last few years in certain areas (and credit to the people who have been willing to fight the good fight). But it's very much a painful experience where you see good ideas shot down and tons of people who want to put their fingerprint on drafts/proposals - it's still a very vendor heavy environment.
Even the vendor representatives are mostly getting paid to post on mailing lists and show up at conferences.
They're not building products, and they're not supporting, visiting or even talking to their customers. Design-by-committee is a full time job that people actually building things for a living tend to not have time for.
> a cellular backup to your residential DSL connection
Hmm, what's the problem? I suppose your home devices should never be exposed to the public internet, and should only be accessible via a VPN like Wireguard. NAT64 is a thing if your home network is IPv4.
BTW what's the trouble with multi-homing? Can't an interface have two separate IPv6 addresses configured on it, the same way as IPv4 addresses?
> BTW what's the trouble with multi-homing? Can't an interface have two separate IPv6 addresses configured on it, the same way as IPv4 addresses?
Because it breaks your network when that router goes away. Your switch ACLs, firewall rules, and DNS records all become invalid because they contain addresses that no longer exist, that your devices continue trying to reach anyway.
Ah, I understand what you likely mean saying "small site multihoming": not a Web site (where it would be trivial), but e.g. a small office.
But with multi-homing you would need to actively test which of your uplinks has Internet access anyway, won't you? And you would have to react somehow when one of your uplinks goes down.
It's easiest to do by abstracting your site away. Make it use a LAN, and do port-forwarding and proxying through a box that knows about the multiple uplinks, and handles the switch-over when one of them goes down. I don't see how it might be easier with IPv4 than with IPv6.
I still assume that you don't want the internals of your office network directly accessible via the public Internet, even when you easily can; VPNs exist for a reason.
You should be using dynamic DNS and firewall rules should be on the subnet boundary in this scenario, any decent firewall (including referee PFsense/OpnSense) support ACLs that follow IPv6 address changes.
The amount of ignorance in these ipv6 posts is astounding (seems to be one every two months). It isn't hard at all, I'm just a homelabber and I have a dual-stack setup for WAN access (HE Tunnel is set up on the router since Bell [my isp] still doesn't give ipv6 address/prefixes to non-mobile users), but my OpenStack and ceph clusters are all ipv6 only, it's easy peasy. Plus subnetting is a heck of a lot less annoying that with ipv4, not that that was difficult either.
I want to send my ssh via my low latency reliable connection, I want to route my streaming via another connection. That’s just a routing rule and srcnat in ipv4
That’s before you go on to using PBR. I want to route traffic with different dscp via different routes.
Ultimately I want the rout g to be handled by the network, not by the client.
IPv4 and nat makes that a breeze.
How is it not a routing rule with ipv6? Firewalls and routers typically support dynamic prefixes (even Vyos, pfSense, openSense do).
How do I tell my phone that I want to send traffic to server A via isp1 and server B via isp2
I wouldn't say "failure". There are many, many IPv6 client devices out there, mostly on mobile networks. And it works great and they do well and the tools all support it very well.
But IPv4 will never, ever die. The rise of NAT as a pervasive security paradigm[1] basically neuters the one true advantage IPv6 brought to the table by hiding every client environment behind a single address, and the rise of "cloud everything" means that no one cares enough about reaching peer devices anyway. Just this morning my son asked me to share a playlist, so of course I just send him a link to a YouTube Music URL. Want to work on a spreadsheet for family finances with your spouse in the next room? It lives in a datacenter in The Dalles.
[1] And yes, we absolutely rely as a collective society on all our local devices being hidden. Yes, I understand how it works, and how firewalls could do this with globally writable addresses too, yada yada. But in practice NAT is best. It just is.
ipv6 adoption is still steadily rising. Not as fast as anyone hoped, but at least steadily. There is no way it can be abandoned at this point even if we wanted to.
I wonder if it could still be usurped by another standard that is somehow more popular. If adoption of that leapfrogs over IPV6 then maybe it will have just been a waypoint along the way.
This absolutely can and should happen
Stripped of all the other baggage that came with it (e.g. SLAAC, IPsec, etc) IPv6 is an incredibly conservative addressing extension. The only thing even more conservative than v6 would have been to drop the lower 64 bits of the address and the associated EUI-64 local addressing scheme. Which... to be fair, that turned out to be a very bad idea, but the length of the field isn't what was holding up v6 adoption.
I suspect by "incredibly conservative" you mean "backwards compatible", which... no. You can't make an addressing extension backwards compatible with hardware that doesn't read all of the address. Of course, we did that anyway with CGNAT, and predictably it causes huge problems with end-to-end connectivity, which is the whole point of IPv6. You're probably thinking more along the lines of an explicit "extension addressing header" for v4. Problem is, that'd mean a more awkward version of IPv6's /64 address split[0], combined with all sorts of annoying connectivity problems. The same corporate middleboxes that refuse to upgrade to IPv6 also choke on anything that isn't TCP traffic to ports 80 and 443. So you'd need Happy Eyeballs style racing between CGNAT IPv4 and "extended IPv4".
Also, that would just be a worse version of 6in4. Because they also thought of just tunneling IPv6 traffic in IPv4 links. I don't think you understand how incredibly conservative IPv6 actually is.
The problem with "incredibly conservative" IP extensions is that nothing beats the conservatism of doing literally nothing. IT infrastructure is never ripped out and replaced unless there is a business case for doing so. The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic", they've only said "let's get more dual-stack hosts online", which is a process that only asymptotes to 100% IPv6, and never reaches it.
IPv4 was not the first version of the Internet protocol. That honor goes to Network Control Protocol (NCP). The reason why we don't have an asymptotic long tail of Internet hosts still demanding NCP connectivity is because this was back when "having a connection to the Internet" meant "having a connection to ARPANET". The US military could just refuse to process NCP packets and actively did this to force people onto IPv4. Now imagine if someone big like Google said "we're going to stop accepting IPv4 connections" - people would jump onto v6 immediately.
[0] Let's say we add a 32-bit extension header onto IPv4
> The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic"…
One of the giant CDNs translates all IPv4 traffic to IPv6 at the edge (stateless NAT46) and is IPv6-only in its core network (for one of its primary product networks; like everybody they have multiple networks.)
> The current problem with IPv6 adoption is that nobody has yet said "let's stop processing IPv4 traffic"
Mobile carriers have done that between consumer devices and network towers. That forced a lot of innovation (including tools like better DNS64 and "happy eyeballs" protocols) and network stack hardening.
The roll out of out CGNAT in some cases is "let's drop IPv4 traffic randomly" and "happy eyeballs" in consumer devices is transparently driving a lot of consumer traffic to IPv6.
This is why mobile and consumer devices are leading the pack on IPv6 adoption.
It's maybe not all of Google that next needs to say "we're going to stop accepting IPv4 traffic", it's maybe more specifically GCP (and AWS and Azure) that need to do that to drive the non-consumer IPv6 push we need. The next best thing would be for all the cloud providers to at least start raising IPv4 address prices until their clients start to feel them.
"Stripped of all the other baggage that came with it..."
But that baggage is a huge part of the problem. Almost nothing you know about IPv4 applies when you switch to IPv6, and most of us found that out the hard way when we tried to make the switch. Leaves a pretty bad taste in your mouth.
I mean this is just wrong. Routing and switching behave exactly the same in V6 vs V4. Details on how you get an IP and what it looks like changed but there's TONS of knowledge shared between the two.
I get so many Second System Syndrome vibes off of IPv6. Surely other people must be picking it up too.
Future proofing it by jumping straight to 128 bits instead of 64. 64 would have been fine. Even with a load factor of 1:1000 by assigning semantics to ranges of IP addresses, 64 bit addressing is still enough addresses for 10 million devices per person.
If we become a galactic empire, we will have to replace the Web anyway because every interaction will have to be a standalone app or edge networking that doesn’t need to hear back from the central office for minutes, hours, days anyway. We could NAT every planet and go on forever.
The point is not really to support a galactic empire, the idea is that you have a network part and an interface part, each is 64 bits. The "network" part is used by routers, the interface part is to identify the device on the endpoint. Each interface have an identifier that is world unique (usually based on the MAC address), each network is also unique. Usually, your ISP gives you a /48 prefix, so you have 16 bits for potentially 64k internal networks. This way, you don't need something like DHCP to get an address, you just take it and you won't have conflicts.
But because you have two independent unique parts, you need twice as many bits, so 64+64=128 bits. It simplifies routing and address allocation, at the cost of 16 bytes per packet compared to 64 bit addresses.
That we could use IPv6 on galactic empires is an added bonus, but not really the reason.
Bypassing the router to get to the device directly via IP sounds like insanity. Like a forever-open port.
Anti nat advocates seem to fall into the “the network shouldnt provide a stateful firewall” camp, because once you have a stateful firewall then nat is a trivial amount of extra bytes and very few issues with modern protocols (ones which don’t embed layer 3 addressing in layer 6/7 messages)
It's a big privacy problem too. Basing your IP address on your Mac address doesn't help in that regard either. Times have changed a lot since IPv6 was invented.
> Future proofing it by jumping straight to 128 bits instead of 64. 64 would have been fine. Even with a load factor of 1:1000 by assigning semantics to ranges of IP addresses, 64 bit addressing is still enough addresses for 10 million devices per person.
128 bit is like the least of adoption issues and basically meaningless difference vs 64.
But it shows weird priorities when they decided 128 then immediately wasted half of it on host part just to achieve "globally unique" host part that isn't really all that useful characteristic of the protocol.
> to achieve "globally unique" host part that isn't really all that useful characteristic of the protocol.
That's the essential part of self-configured addresses in IPv6 that does away with DHCP in most cases. DHCP is a stateful system that has to track every device's addresses individually. You don't need that with IPv6 thanks to this.
IP addresses were always meant to be globally reachable. Of course, NAT has corrupted this - which is why NAT is a scourge.
And so are firewalls?
I kinda think we could fix/save IPv6 by taking away almost everything but the 128-bit address extension.
The truth is nothing needed fixing, or we wouldn't have been in this position 30 years later
Disagree. APINIC got screwed on the IP allocation side, they're the RIR with the largest population but they have a tiny amount of IPs compared to ARIN. India and China have billions of people and not enough v4 space for them. If we go back and reallocate legacy blocks maybe you could make the system work but that would be a big fight with the legacy networks.
v6 restores the end-to-end principle and reduces network complexity once you go v6 only. Not more NAT traversal problems, no need to deal with STUN/TURN, small networks get even simpler with no need for a statefull DHCP server.
Sticking with only v4 space also artificially increases the cost of starting new networks and services because you have to buy space from the entrench IP save owners (unless we change the rules are start charging fees to legacy networks and reclaiming unused or poorly utilized space). Those higher barriers to entry hurt innovation and competition.
So v6 solves several technical and policies issues with the Internet, and maybe that's why we haven't seen speedy adoption. Because people have networks that exist today, some have paid a lot of money for IPv4 space and they want to make the most of that investment.
They don't really have an incentive to implement V6 unless things start to break without it.
I don't think v6 has been a failure half of all internet traffic runs on it! It powers the major cell phone networks, and large tech companies like meta have even gone v6 only in their data centers.
Don't think the problem is 64 vs 128. I don't think the problem is end users either, the vast majority of which don't even know what the IP protocol is in the first place (nor should they). The fault I think is on ISPs.
I use hyperoptic in the UK, if you replace the original router (which reserves the external 443 port for itself, i.e. no one sophisticated would keep it), there seems to be no way to get a v6 address. This is pure incompetence and carelessness. Like ISPs allowing their network to send packets spoofing IPs from outside their network. Add to that foreign ISPs (which means that even if your own network supports v6, you need v4 support when you are on holidays/travelling), and you have a situation where v4 cannot simply be switched off.
So for a website, what is the point of supporting v6 if v4 is never going away?
It's understandable that IPv6 would be ambitious rather than incremental given the cost of rolling out a new protocol; the bells-and-whistles IPv6 design is probably just a relatively small constant factor more expensive than the simplest possible address space expansion. Viewed that way, you only get the one chance to update the protocol, you might as well fix whatever you can.
how would you do SLAAC with 64 bits?
Was DHCP so bad? It carries information important to using such a device anyway.
+1, the majority of corporate networks I have seen used DHCPv6 or similar anyway
well, its not without issues. the actual motivation was not that dhcp is the suxxors, but to promote a model where the assigned prefix was free and highly dynamic.
the goal being to support a model where one could support multiple prefixes to handle the common case of multiple internet connections. more importantly to allow providers to shuffle the address space around without having to coordinate with the end organization. this was perceived to be necessary to prevent the v6 address space from accruing segmentation.
The same way you do it now. The router announces a prefix, and devices negotiate unique addresses.
Keep in mind that SLAAC isn't. Modern IPv6 stacks use privacy addresses, so they still need to run the address collision detection.
There's also a proposal to have SLAAC with longer prefixes, because otherwise you need to use DHCP-PD if you want to have subnetting in IPv6.
You don't, and that's fine.
> Future proofing it by jumping straight to 128 bits instead of 64.
It's hard to disagree with your point since 64 would definitely have been better than the 32 we have. I'm not convinced the choice of going for 128 bits posed any real challenge to adoption though.
The irony that I forgot to voice is that if we had gone 64 and feeder features we’d be farther along in adoption now and probably be consuming the address space at least a fraction as fast as people feared.
By raising the barrier to entry so high we guaranteed the features would likely never be needed.
They did have a proposal for 64bit...was ipv7.
I've been native IPv6 at home for a few years now. That worked flawlessly until a recent Windows 11 update somehow broke IPv6 in ways that I don't entirely understand. All the other Linux and Apple and et cetera things in my house are fine, but the Win11 laptop just refuses to handle certain IPv6 ranges (specifically including the address that the host interface for one of my web servers falls in). 100% contained within the Win11 device and TBH I can't be bothered to dig into it further so I just proxy through some other device that does work. (Guessing it'll get fixed a month/year/decade or so from now.)
I agree it's not a failure, but after 3 decades it's still frustratingly annoying to use at times.
> still hasn't taken over the world
Maybe not in the strict sense, but it kind of has.
In the enterprises I've worked in the past decade with IPv6 running, at least 75% of the Internet traffic is IPv6. In my discussions with other engineers managing large networks, they seem to be seeing more or less that same figure.
The problem is that virtually nobody knows IPv6. I regularly bring up IPv6 in engineers' circles and I'm often the only one who knows much about it. And so, I have doubts about it's long-term future, except for edge cases. I figure some clever scheme utilizing IPv4 and probably NAT will come around at some point.
IPv4s are about to be bought, held, portfoilo'ed, speculated, and rented/mortgaged/sold like real estate. Companies like IPXO are already doing it. The costs of public IPv4's are going to go up for no technical reason because a new distinct ownership layer is springing up between you and the ISP. You're going to start renting them or paying a holder for the right to use them (on top of your ISP to transport it) at some point. And you can continue to do that, or get IPv6's for free.
Just to be pedantic, it's "illegal" to hoard IPv4 or to buy it for any purpose other than using it directly. But yeah, in the real world it may become more financialized than it already is. OTOH if prices keep dropping maybe they won't bother.
Relatedly, I've been seeing some people buying up old domains and squatting on them with AI generated content. Not even ads, but content that seems like something that might actually show up in a rare Google search query. Not really sure what the play is or why this is better than advertising the domain for sale (do registrars punish overt squatting these days?).
We own our own IPv4 and IPv6 ranges, which is nice. There already is a holder for the US: ARIN.net and I hear it's a pretty spendy annual fee for most orgs (we're legacy. we've had ours for decades)
How does one get an IPv6 allocation for free? Or, do you mean the ULA space? Because the latter doesn't really count.
You just ask your RIR. For example: https://www.arin.net/resources/guide/ipv6/first_request/
Looks like that's only for organizations. Even "end users" have to meet the requirements:
>Have an IPv4 assignment from ARIN or one of its predecessors
>Intend to immediately be IPv6 multi-homed
>Have 13 end sites (offices, data centers, etc.) within one year
>Use 2,000 IPv6 addresses within one year
>Use 200 /64 subnets within one year
Seems like they discourage individuals from getting allocations for their own personal use.
right above that is says: "If you meet any of the criteria below, you qualify to receive IPv6 address space:" (emphasis added)
Unless they're very lax about what constitutes multi homed I meet zero of those requirements.
Does me renting a server in a DC count as multi homing? Bridging my network to my friend's place over wireguard? Doubtful tbh
this depends on your RIR. RIPE has far less strict requirements.
A link to a non-commercial guide for IPv6 allocation would be appreciated here.
Yeah. If you're not an ISP or other LIR yourself, the correct path is to ask your ISP or a third-party ISP for a provider-independent allocation. This costs a nominal fee, about $50 per year.
I only know anything about RIPE policies but I gather the PI address processes and fees are very similar between RIPE and ARIN. RIPE has many members that are willing to handle address allocations for the RIPE fee plus 20% (so 60€ per year) and without bundling any other services.
In the end you're still just asking for a block, you don't pay for it. There are requirements which vary from RIR to RIR, sure, but there were requirements for requesting blocks in IPv4 as well originally.
Ultimately, as a regular person requesting IPv6 space you'd just ask your ISP, which can get practically as much as they want for free by submitting these kinds of requests. Meanwhile, for IPv4 space they're going to have a harder and harder time getting you additional space and chances are be unwilling to give it free/cheap.
> as a regular person requesting IPv6 space you'd just ask your ISP
In real life these requests don't lead to IPv6 allocation, no matter how they're asked or how often. Here are a few of the responses I've received just this year.
My current ISP went as far as dumping their own IPv6 allocation. Three weeks ago it stopped being advertised in their ASN. Which I suppose is their way of telling me to stop asking.Past that: Over 15yrs of asking various ISPs (large and small) to make allocations available, none of us ever budged the IPv6 needle.
Now all we need is for someone to make a crypto currency so you can fractionally own IPv4 addresses.
Presumably this would be port-based fractional and 443/tcp would cost a premium.
I was thinking it was more of a "more than 50%" ownership controls the routing tables. Love the chaos.
It's already possible to "split" a frontend HTTP server on a given IP and port to arbitrary backend IPs and ports via the Host header and reverse proxies.
IPv4s have been bought and sold for years
https://auctions.ipv4.global/prior-sales
Prices have been going down in nonimal terms for years, let alone real terms. In terms of investment they're a terrible asset.
IPv6 and CGNAT growth has finally started to suppress IPv4 prices. There was a huge pump when hyperscalers decided they needed more. But IPv6 keeps growing and is the majority of traffic in many networks. If you own significantly more IPv4 addresses today than you need, I would dump them on the market yesterday. Spend some of the profits to move to IPv6 if still needed.
nice. I wish I could buy an address instead of renting from aws...
It seems like the addresses cost about $20 each, and can be rented out for ~$5/year.
That doesn't seem terrible.
> Maybe not in the strict sense, but it kind of has.
I challenge you to find:
1. A hotel in the US that provides IPv6. I have NEVER been in one, and I once stayed in a hotel (in Mountain View, CA) that was giving out public IPv4 addresses.
2. An easier task: a SIP provider that has IPv6 (in the US). You know, for the VoIP that is supposed to be a poster child of end-to-end connectivity.
> In the enterprises I've worked in the past decade with IPv6 running
What about those without IPv6 running?
Anyway, in the enterprises I've worked in the past decade - of course, another anecdote - not once has anyone ever specified an IPv6 address of anything. Inside the organization or outside of it.
> not once has anyone ever specified an IPv6 address of anything. Inside the organization or outside of it.
If you deploy IPv6 correctly, you shouldn't have to disclose IPv6 addresses to users inside or out -- DNS keeps the address literals abstract, hidden from users.
why would an enterprise turn to IPv6?
everything fit's nicely in the 10.0.0.0/8 range
in my many decades of enterprise infrastructure, no-one has ever mentioned IP6 either.
why would they, whats the business case?
The problem with private address ranges is that everyone thinks they're available. In a large enough enterprise you're bound to have conflicts. They usually pop up at the most inconvenient time and suddenly you're cosplaying ARIN in your IT department.
> everything fit's nicely in the 10.0.0.0/8 range
Except during a merger/acquisition and both companies have 10.0.0.0/24 in their OSPF or IS-IS topology.
Unless you get to big. Or you merge with another company and have to combine your internal networks and oops, all the subnets are overlapping. Or you need to serve mobile clients who get better connectivity over v6.
Grow large enough and you hit the limit pretty fast. NAT complicates things.
The best one is async routing. You have a NAT, they have a NAT, you VPN together and think you have different IP address ranges, but unknown to the operator there's a little internal network with an overlap at the end of some slow line that is now getting flooded with internal traffic that's trying to go to a completely different network.
you haven't had to set up intercompany vpns I see
Indeed I have not. But I suspect most people, and most companies, have not either.
I don't claim IPv6 isn't used anywhere, or even that it's not used a lot.
Pretty much every fortune 500 company does, which counts for millions of people on their networks every day. The troubleshooting calls for VPN routing vs internal LAN routing are fun endeavors of who is actually willing to take responsibility for things they don't understand.
Somehow still easier than v6.
if both you and companies you have site to site vpn with have IPv6 there is no IP conflict or NAT to worry about.... and that's about end of the advantages
one poorly made decision and oops you're out of 10/8 addresses
if you've never run in to this, then sorry, you've not been in an enterprise, you're in a mom 'n pop shop cosplaying as enterprise.
I am on my company's VPN right now and I get a 0/10 at test-ipv6.com
>Maybe not in the strict sense, but it kind of has.
>In the enterprises I've worked in the past decade with IPv6 running, at least 75% of the Internet traffic is IPv6.
Nobody cares about those. What matters is if my device has an IPv6 address assigned.
Ok then: most people in the US do. The rest of the world is looking increasingly ipv6 too: https://www.google.com/intl/en/ipv6/statistics.html#tab=per-... India is 71% IPv6 (probably thanks to Jio), China has it in its 5 year plan, Europe is doing well, etc
Wasn’t it mandated for 4G? Or at least 5G?
> at least 75% of the Internet traffic is IPv6.
> Nobody cares about [that]. What matters is if my device has an IPv6 address assigned.
This seems to be the weird dichotomy in these comments. Some people are arguing from the position that is absolutely everywhere and is doing great.
Others are saying since their machine doesn’t show it it’s dead and no one cares.
Is there a term for this? A successful failure? A failed success?
Kind of odd.
Maybe the False Consensus Effect?
https://en.wikipedia.org/wiki/False_consensus_effect
Everything I know about IPv6 comes from this one blog post: https://apenwarr.ca/log/20170810. It’s from 2017, when IPv6 adoption was 17% according to https://www.google.com/intl/en/ipv6/statistics.html; today it’s close to 50%.
Is that worldwide adoption or adoption in the US? China went from almost nothing to 77% adoption is just a few years because they included it in their last 5-year-plan. How much of that adoption would be explained by China alone
Google's stats are Google International, i.e. everywhere Google provides service. Whether that includes China depends on the whims of the Politbüro.
I'd assume a lot of this is because of mobile devices of some type. Getting legacy network operators like cable providers to supply IPv6 has been hell.
> Getting legacy network operators like cable providers to supply IPv6 has been hell.
In my experience it's actually the large enterprises that are having issues.
Eyeball networks and cloud providers have been implementing IPv6. In the US all major phone carriers are v6 only with XLAT, the large residential ISP all have implemented v6 (Charter/Spectrum, Comcast/Xfinity, altice/optimum). The lagging networks are smaller residential ISP and enterprise networks.
In Asia they've implemented v6 everywhere pretty much because their v4 allocation is woefully insufficient. APNIC has like 4 billion people in it but less IP space than ARIN, with a population of less than 500 million.
Just because the ISPs have implemented IPv6 doesn't mean anyone's home router is using it, let alone all the devices in the home WiFi
they should have made it backwards compatible. they were forever doomed by not make it a superset of IPv4.
https://www.google.com/intl/en/ipv6/statistics.html it's still going up (we are in some sort of cyclic downturn right now that I don't understand).
Next year that chart will finally cross 50%. It was a mere 30% in 2030. Developing country mobile phone networks will continue to push it higher.
All we need to do is start having rich governments mandate IPv6, and also mandate IPv4 downtime as a punishment for those that don't comply / chaos engineering for the system as a whole. Then we can quickly finish the job.
> we are in some sort of cyclic downturn right now that I don't understand
consumer networks have significantly higher adoption rates compared to corporate/edu, and people are on vacations during summer
Ah OK, there are workday/weekend and vacation/no-vacation cycles. Gotcha.
Well, to the extent the rich country laggards are institutional, then regulation should be more effective!
I was in college when v6 was going through the RFC process. In my networking class we had to learn Netware (IPX) and v6, which have both turned out to be equally irrelevant, for different reasons. At this stage, I fully expect to retire having never deployed a single resource using v6.
I was expecting Google's IPv6 availability monitor[1] to show a crossover to a (slim) majority of their users accessing their services over IPv6 sometime soon, though it's sort of fascinating how close it gets to 50% recently without ever actually crossing over:
[1] - https://www.google.com/intl/en/ipv6/statistics.html
Heh, 49.84% on Aug 2nd. Pretty sure it'll cross 50% in 2026, even if only for a few peaks.
I remember 10+ years ago we were going to run out of IPv4 addresses and it was the next Y2K unless you adopted IPv6. I was able to get IPv6 for my servers and home, and I thought I was safe!
> "In fact, IPv4's continued viability is largely because IPv6 absorbed that growth pressure elsewhere – particularly in mobile, broadband, and cloud environments," he added. "In that sense, IPv6 succeeded where it was needed most, and must be regarded as a success."
Apparently it turns out IPv6 wasn't for me any way!
Yesterday I was required to turn on IPv6 on my router, while setting up some IoT things using Matter over Thread. Apparently that protocol uses IPv6 and doesn't work if your router is only routing IPv4.
There is a rich history of IoT devices using IPv6 to communicate among themselves without relying on the cloud. I think Nest started this trend. One Nest device sends a specific RA to make itself the router of all other Nest devices. All other devices can configure themselves thanks to SLAAC. The benefit of v6 is that there are so many addresses out there that the Nest device can just pick an arbitrary ULA and there won’t be collisions.
Don’t know about Matter though. If it requires the user to turn on IPv6 then it’s a user experience downgrade. It should just use IPv6 internally as an implementation detail.
That's incorrect. Matter-over-Thread absolutely does NOT require IPv6 on your router. Even Matter-over-WiFi will happily work in IPv4-only networks, as long as your router does not filter the IPv6 announcements.
Some routers can work as _relays_ between the Thread network and WiFi, but this is entirely optional.
I'm genuinely wondering if western governments (UK) will start issuing ipv6 addresses out to citizens as their digital id so they can track them online and offline.
Only half joking, some UK MPs might actually consider this a reasonable thing considering how many ipv6s there are.
That wouldn't work anyway. IPv6 addresses aren't routable on an address-by-address basis.
But Mobile IP could do it https://www.rfc-editor.org/rfc/rfc6275
Yeah but the digital ID could be the 64bit suffix of the IP. Kind of like that horrendous and moronic idea of using the MAC address as the suffix.
Whether it's workable or not it's besides the point when certainly the UK gov gets it in mind to implement.
Since ipv6 is just a 128-address, you could say any unique national ID is already an assigned ipv6. Heck, if you assign your services a UUID, you have also already assigned them an ipv6.
What makes an ipv6 useful is that you can route to it. Since you will never be connected to the network. The network will never be able to route packets to you, making the whole thing a little pointless.
We're not routable yet. Fairly certain people are trying to create computer/brain interfaces...
I'm thinking the gov issuing you an ipv6 address that you must use to connect to the internet. But it's also you're id too, since nearly all services are either online or getting pushed that way.
IPv6 has already won on mobile and been gaining fast traction in IoT space with Matter. The reason IPv4 is still around everywhere else is because we came up with ingeniuous techniques that squeezed the heck out of IPv4 address space. Also, IPv4 addresses are easier to type. That's pretty much it.
I had mentioned some of that in my post: https://ssg.dev/ipv6-for-the-remotely-interested-af214dd06aa...
Yes, they are easier to type, and to remember, and it turns out, that's actually a big deal! When you are troubleshooting network problems, it's really nice to take everything but simple raw addresses out of the picture. It's really nice to be able to look at am address and instantly recognize if it's on the same (V)LAN as you are expecting, if it's unique, if it changed from what it was last time you checked, if it's an address for a VPN interface, if the packet you are sniffing is for this host or that host, if DNS is resolving correctly, etc., etc.
It was doomed the moment you had to maintain two separate stacks, each with its own address, firewall rules and so on.
It should have been ipv4 with extra optional bits, so you could have the same rules and everything for both stacks.
I turn it off because it's a risk having one of either stacks malconfigured.
IPv6 should've been a superset of IPv4, as in addresses are shared, not that you have a separate IPv4 and IPv6 address for your server.
That’s why my home network is IPv6 only. NAT64 and DNS64 and 464XLAT work very well, and you only need to configure IPv4 once: in your router, where you need special configuration anyways.
Another day, another Godwin's law of networking.
>It was doomed the moment you had to maintain two separate stacks
Pray, tell me, how are we supposed to extend IPv4 with another {insert a number here} bits without creating a new protocol (that neccessitates running two stacks)?
Suppose that you have an old computer that understands only 32 bit addresses -- good ol' IPv4. Let's name it 192.168.10.10.
It then receives a packet from another computer with hypothetical "IPv4+" support, 172.12.10.98.12.4.24.31... ...Wait a minute, it can't, because your old computer understands only 32 bit addresses!
What if we really forced it to receive the packet anyway? It will see that the packet is from 172.12.10.98, because once again, it understands 32 bit addresses only.
It then sends back the reply to... you guessed it, 172.12.10.98. Not 172.12.10.98.12.4.24.31.
Yeah,172.12.10.98.12.4.24.31 will never get its reply back.
Do you see why any "IPv4 with extra octets" proposal are doomed to begin with now?
It wouldn't be able to receive it. That simple. Which is not a problem, any server would still have an old ipv4 address (172.12.10.98 from your example), like they currently do and probably will for decades.
My ISP refuses to give you a static IPv6 prefix unless you're a business customer, despite having an "unlimited" amount of them. This results in me not bothering to set it up properly and focusing on IPv4 still.
For those in the UK who want a static IPv4 or IPv6 block AAISP offer a L2TP service for £2/month. It's limited to 3 megabit/s but might be enough for some use cases.
My ISP is xfinity. They say the same thing but my IPv6 address hasn't changed any more frequently than my IPv4. In my experience it changing isn't any more annoying than my v4 changing so I'm not sure why people still get up in arms about it.
In about a year of treating my comcast-assigned ipv6 address as static, it changed once.
Sadly, this happened despite me specifically requesting the same address as always. That caused me some grief. But it's not common.
My xfinity ipv4 changes once every few years, if that. I treat it as static and update things if or when it changes, which fortunately isn’t too much work. I never requested anything special regarding it, and I have a normal/non-business account. I wonder why some change often and others don’t?
I had Xfinity for 4 years and my IP changed once in that time! Now I have fiber from centurylink, and it changes anytime I need to reboot the fiber modem or my firewall. Different companies, same metro area though. That too makes me wonder about how both manage their allocations give the difference in IP assignments.
On the other end of the connection, there are physical servers and routers. Every once in a while they change how things are connected/deployed for maintenance, upgrades, etc.
Pretty much, I have my cable modem on continuous power and it will keep the same address pretty much forever. Two times it changed is when I had a 48 hour power outage and shut everything down, and the other time was maintenance at the cable companies side where they rebooted their equipment.
Get a virtual server and do the things on it that you'd want a static address for. Use a VPN connection back to your home to merge it with your network. This is a great way to deal with CGNAT.
Do you have a static IPv4, presumably a single IP?
I find it useful, mine does change periodically, but I just have a script that Updates DNS when it changes:
Sure some services might notice for a bit, but it's plenty good for me.I don't have a static IPv4 address and I have to use a DDNS built into the Caddy plugin on my OPNSense router. From what I understand, you can't get a static "local" (I know, IPv6 has no direct equivalent) address to use for a reverse proxy — at least not in an easy manner. I might be completely wrong but that's why I don't bother with IPv6.
You’re looking for a Unique Local Address there. It’s a non-externally-routable address that you can use for internal connections.
https://en.wikipedia.org/wiki/Unique_local_address
Yep. ULA addresses are the equivalent of 10.0.0.0/8, 192.168.0.0/24, and 172.16.0.0/12 space. [0] And you can use them to do NAT, just like with IPv4.
The huge difference from the IPv4 world is that the procedure for generating your /48 ULA prefix ensures that it's very, very unlikely that you will get the same prefix as anyone else. So, if everyone follows the procedure, pretty much noone has to worry about colliding with anyone else's network.
Following the procedure has benefits. For example, VPN providers who want to use IPv6 NAT can do that without interfering with the LAN addressing of the host they're deployed to... companies that merge their networking infrastructure together can spend far less (or even zero) time on internal network renumbering... [1] etc, etc, etc.
[0] And link-local addresses are the equivalent of 169.254.0.0/16 space.
[1] Seriously, like a year after one BigCo merger I was subject to, IT had still not fully merged together the two company's networks, and was still in the process of relocating or decommissioning internal systems in order to deal with IPv4 address space constraints. Had they both used ULA everywhere it was possible to do so, they could have immediately gotten into the infosec compliance and cost-cutting part of the network merging, rather than still being mired in the technical and political headaches forced upon them by grossly insufficient address space.
Problem with ULA is that it's functionally useless on a dual-stack network, because clients will attempt to use IPv4 before they attempt to use ULA.
https://blog.apnic.net/2022/05/16/ula-is-broken-in-dual-stac...
Note that although the policy is that you choose a random prefix, nothing actually enforces this and nothing stops you using fd00::1, fd00::2, etc just like 10.0.0.1 etc.
Same here, I had a working IPv6 setup previously with my DSL provider, but now that I moved to a fibre connection, the new one refuses to support it.
My ISP (naming no names...erum...Spectrum) refuses to even admit they know what IPv6 is. It's like asking the NSA what Menwith Hill is for...
I've had v6 on spectrum for 5 years
https://www.spectrum.net/support/internet/ipv6
https://www.spectrum.net/support/internet/ipv6-faq
> IPv6 is available today with an IPv6 capable modem in the majority of Spectrum’s footprint.
But do they give you PD?
My prefix is tied to the mac address of the device that's connected to the PON.
I recently moved house and looked at a new offer from a new ISP for a long term lockin but a cheap price. They used CG-NAT. I instead chose one which gives me as many ipv4s or ipv6s as I can reasonably use, doesn't oversubscribe its upsteam connectivity etc.
For home internet service I would prefer to pay extra for a better service, it's too important to try to penny-pinch 0.1% of my income on it.
But then I live in a capitalist country where there's competition, I believe some countries you don't get a choice.
FYI it's practically impossible not to oversubscribe your upstream connectivity unless they either spend way too much money or offer very slow service to users. Consider ten thousand users with 1G connections - should they have 10 terabit upstream?
The more practical thing to look for is that they aim to upgrade it based on need, instead of arbitrarily throttling the users.
Where I live the cable system is fine, and the cellular system is fine... until one goes down, then the other gets flooded with traffic and stops working leaving no internet at all.
The problem with IPv6 jokes is that very few people are making them.
DJB understood the problem decades ago. https://cr.yp.to/djbdns/ipv6mess.html
Not really. DJB’s clearly a very, very smart person, but he missed the mark on almost all of that. The problems he described which are real have been satisfactorily solved; they weren’t intractable. The rest turned out to be non-issues.
IPv6 continues to rumble along, gaining market share, because China. Increasing IPv6 adoption was in the 14th Five Year Plan, and about 75% of mobile in China is now IPv6.
I started looking at self-hosting many applications at home once I realized that IPv6 could enable me to do that securely without any complicated router/firewall configuration that would need to be maintained.
The only wrinkle I ran into is that apparently ISPs are still reluctant to give out static IPv6 prefixes to residential customers. So you still need some kind of DDNS setup, which is lame.
btw it's only been getting seriously deployed since 2010
and it never will, because IPv4 has become a defacto reputation system for the exact same reason that IPv6 was created: a limited supply. It wouldn't surprise me to see the continued balkanization of the internet that there is a particular underclass of exclusively IPv6 traffic, but its not going to take over everything because once decentralized systems are now in the hands of a few decisionmakers in the case of, say, email.
Is there yet answer to question "how to get random self-assigned addresses into dns records, firewall rules and switch acls?" ?
Dynamic DNS, DHCP, and static assignment are all still part of IPv6. Putting single IPs in switch ACLs is an anti pattern. Consider zero trust or working with whole subnets(they're plentiful in v6) instead.
"Build yourself an IPAM solution, at great operational cost and complexity."
I have noticed that on my last Windows computer (Windows 10) and my current computer (Windows 11) IPv6 works great for a little while after a reboot, but then just seems to die. I have my house and all internal automation configured for IPv6 first and its great on all my Linux computers and phones.
I love IPv6 but organizations seem to struggle with it. My ISP, for example, had issues routing it after a backend update so they decided to just turn it off. I'm now stuck on CGNAT IPv4 which results in constant captchas :/
Meanwhile, there is a whole grey market built around this. People sell “CGNAT mobile proxies” that ride on carrier and ISP NAT, and the whole point is that they are a pain to block without nuking huge ISP ranges. So they get marketed as a convenient way to dodge shadowbans, spam filters, and basically any abuse defense that relies on IP reputation.
> the whole point is that they are a pain to block
What makes them a pain to block? Angry users or some central database that lists these addresses as "do not block"?
> What makes them a pain to block?
Not wanting to cut off access to your users from, for example, every AT&T device (and their MVNOs).
It would be nice if we had a blackout CGNAT day where a bunch of major sites don't serve traffic to people behind CGNAT to give the ISPs a bit of a scare.
It kind of has. The majority of internet traffic is IPv6. The three biggest internet hub regions (USA, Europe, China) have IPv6 mandates. Most apps support IPv6. Google and Apple force them to, od they get kicked off the app store. Almost all mobile networks (which means almost all end devices) are IPv6-only, with slow inefficient tunneling for IPv4. The price of IPv4 addresses is declining.
At what point will we be allowed to say IPv6 hasn't failed? When the IPv4 internet finally switches off for good? It feels like no achievement is high enough for those who don't like IPv6 to change their minds. I would've thought making up 50% of internet traffic and 50% of end devices being on IPv6-only networks would be good Schelling points, but evidently they're not!
The majority of traffic might be IPv6, but the majority of people using and understanding IPv6 is not.
> At what point will we be allowed to say IPv6 hasn't failed?
"IPv6 ... still hasn't taken over the world [after thirty years of deployment]." is a very different statement than "IPv6 has failed.".
Noone who has successfully extracted their head from their ass says that IPv6 has failed. It's widely deployed on the Internet, and on who knows how many corporate intranets and SOHO/home LANs.
IMO, it's stupid to ever consider turning off IPv4. There surely exist useful systems out there that will never be updated to work with IPv6.
I see IPv6 as an "IPv4 address pressure relief system". In the future, SOHO/home LANs can run servers on IPv6, datacenters can run servers mostly on IPv6 but also v4 if they really want, and SOHO/home networks can be behind an IPv4 CGN because all of their unsolicited inbound traffic will come over IPv6.
>IPv6 ... still hasn't taken over the world [after thirty years of deployment]." is a very different statement than "IPv6 has failed.".
It's incredibly likely that the GP was referring to comments in this thread, which were indeed claiming that IPv6 has failed, despite the fact that its deployment has been steadily climbing up worldwide.
By the way...
>In the future, SOHO/home LANs can run servers on IPv6
The future is now. My web server is IPv6 only precisely due to the same reason you mentioned: my ISP has put me under a CGNAT. People can still connect to my website through the Cloudflare reverse proxy though (which I have only enabled for IPv4, IPv6 users get to enjoy direct connection).
IPv6 addresses are ugly and hard to memorize. IPv4 addresses are pretty and easier to memorize. That's about the end of the discussion as to why it's basically a failure.
Contrary to some other comments: no, IPV6 hasn't taken over the world at all.
In my case, I administrate a small server at home, where I self host many services that are made available to myself, friends and families, over the internet.
In that context, IPv6, is SADLY (please note that I have NOTHING against IPv6), a limitation, even a nightmare to use.
Some programs do not handle IPv6 at all. Game servers for instance, do not support it, the one that I think about is: Arma 3. But there are many others
In 2025 (and 2026 too?), 4G (5G?) operators do not all route over IPv6 -> which means that if your domain only has a AAAA record, some people using 4G will not be able to access ANY of your services. This issue forced me to beg my ISP to obtain an IPv4 "fullstack" as they call it.
Without that IPv4 you have to go through some kind of tunneling (like Cloudflare) -> and guess what? Cloudflare sometimes crashes (it happened super recently remember?) and in that situation -> ALL your services accessible through the tunnel are "down" for your users. Plus, it is EXTREMELY unsatisfying to rely on an external private-owned service for a selfhosting project.
In almost ALL context IPv6 is seen as optional, additional, additional configuration and is NEVER the default. NEVER. Which means: more configuration, possibly more struggle.
>ALL your services accessible through the tunnel are "down" for your users
Not all.
I operate site with IPv6 only origins behind cloudflare.
During the outage I manged to login to the dashboard after some time and remove cloudflare for nearly 2 hours, and traffic level stayed close to 50% during the IPv6 only period.
Nobody complained: those who did not have working IPv6 probably blamed it on cloudflare.
> traffic level stayed close to 50% during the IPv6 only period.
> Nobody complained: those who did not have working IPv6 probably blamed it on cloudflare.
You described a situation where the outage resulted in 50% of your customers were unable to reach you and you were unable to do anything about it. I don’t think this story is a win for IPv6, regardless of whether your customers blame CloudFlare or not.
Compared to 0% like others?
50% is a very substantial retention rate.
Would hand been 100% if his site supported ipv4 natively instead of relying on CloudFlare to do the translation.
so it turned into a good ol' legacy problems
idk if arma3 does server discovery, but in case of manual ip input there some kind of OS-networking-level adapter should help. Usecase seems too obvious for something like that not to exist
Most 4G networks are actually IPv6-only, with IPv4 traffic being routed through inefficient tunnel systems. This is why Apple and Google require all mobile apps to use IPv6.
Certainly not all networks. Optus (Australia's #2 carrier) for example does not support IPv6 at all on their mobile network.
I have fiber to my house and no native IPv6 support. I did some research and it seems there is a way to enable IPv6, but it’s janky and just tunnels over IPv4 so what’s the point?
I would love for IPv6 to actually take off but somehow it feels like we are still a decade away from ubiquitous adoption.
> In almost ALL context IPv6 is seen as optional, additional, additional configuration and is NEVER the default.
Weird. The past two ISPs I've had (Comcast and Monkeybrains) both had IPv6 enabled by default. I've looked at a bunch of SOHO networking gear and IPv6 is on by default. On every Linux and Windows system I've touched in the past ten, fifteen years you have to go significantly out of your way to disable IPv6.
> Some programs do not handle IPv6 at all. Game servers for instance, do not support it...
Depends on the game server. Many I run absolutely do.
Your complaints smell like you tried to run an IPv6-only client network, which would be an absolute nightmare. That's just a stupid thing for a SOHO network (and the networks that serve most corporate client hosts) to do. IPv4-only Internet hosts exist, so it's a no-brainer to provide IPv4 connectivity to clients.
On the other hand, running IPv6-only infrastructure networks can make a ton of sense. One very large such operator is Comcast, a US ISP.
IPv6-only is the future for mobile phones, and mobile devices are the future of the internet.
And it is consumer devices (and IoT devices) which are the most numerous and also the most price sensitive, and this is where IPv4 is disappearing first.
IPv6 might not have taken over the world, but it sure seems to be getting forced on the world.
Even more than IPv4, not knowing enough about IPv6 can introduce a lot of unintended issue, consequence and even security gaps in your assumptions.
Maybe there was an IPv7 or 8 that will be more palatable.
It's reaching around 50% adoption according to Google stats? Steady growth, though still annoyingly slow. It will need a few more decades at this rate.
Is IPv6 going to see it's epitaph instead of it's takeover soon?
reminder that in 2026 Microsoft GitHub(TM) still doesn't support ipv6
but if you need maximum AI slop, that's everywhere
As GitHub keeps Azureifying, it'll be interesting to see if this changes.
The article itself is fairly short & fluffy.
Vs. real meat is in the comments on the Register's site.
> "IPv6 wasn't about turning IPv4 off, but about ensuring the internet could continue to grow without breaking,"
Then it's failure is by design. I should not want to multiplex/bridge different versions of the network-layer protocol; and certainly not to avoid using the new protocol because the old one seems more usable and approachable.
I think the original plan was definitely to turn IPv4 off. Obviously that's probably not practical in our lifetimes.
it was an explicit non goal to ever schedule the end of ipv4
My "conspiracy theory" is IPv6's point to point connectivity is inconvenient to anyone except end users. And, rent-seekers can't extract money if the ranges aren't limited. American mind can't comprehend not rent-seeking any new invention.
Oh it's much more mundane.
IPv4 "works" and ISPs are incredibly resistant to changing things that "work".
Because support is needed basically end to end, it's going to take an ungodly amount of time for ISPs to figure this stuff out.
It's pretty frustrating having all my hardware support v6 with the only barrier being my ISP who refuses to support it in my location (they support it in other locations).
America has one of the highest IPv6 adoptions in the world.
> America has one of the highest IPv6 adoptions in the world.
Except for people. Specifically, wireline end users. Triply so if they're on Fiber.
ex: T-Mobile fiber rollout is IPv4-only and CGNAT.
Conversely, their mobile network is the only 100% – or near 100% – IPv6.
For Google connecting clients it's only half the internet.
Half. The. Internet.
What a failure. /s
This is mainly due to mobile devices only being issued ipv6 addresses by the telco 4g networks. They are the only ones using ipv6 on the millions of clients scale.
Comcast/Xfinity implemented v6 on their residential cable network 14 years ago ( https://corporate.comcast.com/comcast-voices/ipv6-deployment...)
Most other large eyeball networks have as well.
My current home ISP and my last one both support IPv6 just fine. It is not a mobile-only thing.
Everything supports both. We are talking about being issued only IPv6 addresses where you actually use it to connect to stuff.
Most mobile devices are only issued an IPv6 address and therefore when the masses do google searches it uses IPv6 and makes it look like there is huge adoption.
Unsurprisingly Google actually does also have IPv4 addresses. What they're measuring isn't "How did you reach our servers?" but instead "Could you have reached our IPv6 servers?"
So that measures everybody who has working IPv6. https://www.google.com/intl/en/ipv6/statistics.html
> We are talking about being issued only IPv6 addresses where you actually use it to connect to stuff.
You seem to be asserting that dual-stack machines use IPv4 by default, but that's not really true. If your machine has both IPv4 and IPv6 connectivity, browsers will in fact use IPv6 to connect to sites that support it, like Google. They prefer IPv6 by default and fall back to IPv4 if IPv6 is slower (Happy Eyeballs algorithm).
Of course, random software can mostly use whichever it wants, so I'm not claiming every process on such a machine will use IPv6, but most common stuff does.
Still disabled on all my networks and will be forever. Incoming HN downvotes because I'm not using the coolest latest technology.
ipv4 accidentally provides "casual anonymity" and "one ip does not identify device", which is incredibly important in this age of overbearing surveillance by government and private companies. ipv6, even with the "privacy extensions", is one subpoena away form directly identifying your individual device. ("ISP X: who did you assign this block of ips to on Y date?")
ipv4 has a boatload of issues (the worst of it is probably the unused and 'dangerous' flags), and ipv6 offers a boatload of cool features (The most beautiful is probably the flow state tracking).
However ipv6 was designed in a naive vacuum where no one possibly imagined the internet being abused to destroy an individual's inherit right to anonymity.
Oddly enough, the people most hellbent on spying on you: Facebook, Google, etc are the ones screaming for ipv6 the loudest.
It’s ok to understand something and disagree with it. It’s another to proudly wear ignorance on one’s sleeve. That’s never a good look.
There’s no way in which IPv6 is less private than IPv4. An ISP issues your house an IPv4 address and an IPv6 /48 network. Both of those can be subpoenaed equally. The privacy extensions work as advertised.
And in reality land, the big companies are the ones pushing for the upgrade because they’re the ones hardest hit by IPv4’s inherent limitations and increasing costs. Same rando in Tampa isn’t leading the charge because it doesn’t affect them much either way.
> There’s no way in which IPv6 is less private than IPv4
With IPv4 behind CGNAT you share an address with hundreds of other users. This won't protect you against a targeted subpoena, but tracking companies typically don't have this kind of power, so they have to resort to other fingerprinting options.
On the other hand, an IPv6 address is effectively a unique, and somewhat persistent, tracking ID, 48/56/64-bit long (ISP dependent), concatenated with some random garbage. And of course every advertiser, every tracking company and their dog know which part is random garbage; you are not going to fool anyone by rotating it with privacy extensions.
CGNAT is nowhere near the common case yet. And frankly, I’m horrified that anyone’s describing it as a good thing. CGNAT is the devil, even if it accidentally has one not-terrible feature, and especially when ISPs realize that they can sell those NAT logs to companies who still want to track end users.
For tracking purposes, an IPv6 address is 48 bits long. That’s what identifies a customer premise router, exactly like a IPv4 /32 identifies one. The remaining 80 random bits might as well be treated like longer source port numbers: they identify one particular connection but aren’t persistent and can’t map back to a particular device behind that router afterward.
>CGNAT is nowhere near the common case yet. And frankly, I’m horrified that anyone’s describing it as a good thing.
For some reason, "CGNAT == privacy" is a very common sentiment on Hacker News. Yeah, Hacker News. It's bewildering, and after my last comment [0] talking about it, I have kinda already given up trying to convince people that CGNAT is devilish and not at all a privacy protector.
[0]: https://news.ycombinator.com/item?id=40180058
Google aren't subpoenaed
Perhaps this is the difference, some people are concerned with being anonymous from companies like google, amazon, etc. Some don't mind that, as long as they are anonymous from a government.
Your mention of subpoena suggests you don't care about google tracking you.
Google gets subpoenad all the fucking time. They have whole departments set up to handle the case load.
Some public evidence: https://www.alphabetworkersunion.org/press/google-lays-off-c...
Sorry I meant to say google aren't subpoenaing
The people I want to protect my privacy from are google, facebook, amazon, they can't subpoena my IP, they can track me just fine though.
I was directly replying to someone saying they could subpoena the temporal owner of an IPv6 address, as though that were somehow different than IPv4.
The tracking is a moot point. You can be tracked using the same technologies whether you connect though v4 or v6, and neither stack has the advantage there.
Unless my understanding of how IPv6 is flawed, I don’t think your assertion is true in practice. One of the big benefits to IPv6 is that addresses are plentiful and fairly disposable. Getting a /48 block and configuring a router to assign from the block is pretty straightforward.
I’m aka unsure if IPv4 really gets you the privacy advantages you think it does. Your IP address is a data point, but the contents of your TCP/HTTP traffic, your browser JS runtime, and your ISP are typically the more reliable ways to identify you individually.
> Incoming HN downvotes because I'm not using the coolest latest technology.
The downvotes are because you’re needlessly combative, preemptively complaining about downvotes.
You can nat all your ipv6 traffic behind a single IP if you want. Or a new IP for every connection.
Realistically though there's enough fingerprinting in browsers to track you regardless of your public IP and whether it's shared between every device in the house or if you dole out a routable ipv4 to every device.
CG-NAT gives more privacy benefits as you have more devices behind the same IP, but the other means of tracking still tend to work.
For me I just don't see the appeal of supporting both ipv4 and ipv6. It means a larger attack surface. Every year or two I move onto my ipv6 vlan and last a few hours before something doesn't work. I still don't see any benefit to me, the user.
> Realistically though there's enough fingerprinting in browsers to track you regardless of your public IP and whether it's shared between every device in the house or if you dole out a routable ipv4 to every device.
Yes, browser fingerprinting is a big issue, but it can be mitigated. The first thing everyone should do is to use a network-wide DNS blacklist against all known trackers (e.g. https://github.com/hagezi/dns-blocklists) and run uBlock Origin in the browser.
You can go further and restrict third party scripts in uBlock, or even all scripts. This will break at lot of websites, but it is a surefire way to prevent fingerprinting.
Then of course there is Tor.
IPv6 itself seems to provide a larger attack surface based on IPv6-specific CVEs. I don’t know if it’s the added complexity or that it’s treated as a second class citizen by devs, but I still see a solid number of these coming across the CVE feed.
This one was particularly scary: https://malwaretech.com/2024/08/exploiting-CVE-2024-38063.ht...
When something happens over IPv4 people treat it like "the Internet has malicious actors, water is wet", but when it happens over IPv6 it must be IPv6's fault.
Sigh...
> Realistically though there's enough fingerprinting in browsers to track you regardless...
Yep. For the OP, IPv6 "Privacy" addresses do what he's looking for. You can change how long they're valid for on Linux, so you can churn through them very frequently if you wish.
> Every year or two I move onto my ipv6 vlan and last a few hours before something doesn't work.
Odd. I've been using IPv6 for like fifteen, twenty years now with no trouble at all. If you've been using a "single stack" IPv6-only network, well, there's your problem.
> For me I just don't see the appeal of supporting both ipv4 and ipv6. It means a larger attack surface.
The attack surface with IPv6 is exactly as large as if each of your LAN hosts had a globally-routable IPv4 address. Thinking otherwise is as smart as thinking that the attack surface on a host increases linearly with the number of autoconfigured IPv6 addresses assigned to that host from the same subnet.
If you don't want the IPv6 hosts on your LAN to be reachable by unsolicited traffic, set the default policy for your router's ip6tables FORWARD chain to DROP, and ACCEPT forwarded packets for ESTABLISHED or RELATED connections. If you're not using ip6tables, do whatever is the equivalent in the firewall software you're using. If you know that you have rules in your FORWARD chain that this change would break, then you already knew that you could simply drop unsolicited traffic in the FORWARD chain.
Unrelated to that, I see no reason to get rid of IPv4.
I expect that the future will be that nearly all "residental" [0] and non-datacenter business connections provide globally-routable IPv6 service and provide IPv4 via CGNAT, as IPv6 will be used for servers deployed at these sorts of sites. [1] I expect that the future will be that all datacenters and "clouds" will provide globally-routable IPv6 to servers and VMs, and globally-routable IPv4 to the same by way of load balancers.
So, home servers [1] will use IPv6, datacenter and "cloud" servers will use IPv4 and IPv6, and "legacy" devices that work fine but will never have their IP software updated will use IPv4.
I see IPv6 as a "reduce the pressure on the IPv4 address pool" mechanism, rather than a "replace IPv4" system. Again, I see no reason to get rid of "short" IP addresses. Default to using "long" ones, and keep the "short" ones around just in case.
[0] I'm including people's personal mobile computers in this definition of "residential".
[1] "Servers" here include things like "listen" video game servers or short-lived servers for file transfers and stuff like that.
> Incoming HN downvotes because I'm not using the coolest latest technology.
"IPv6 just turned 30" - literally the first part of the post title.
The rest of the post is equally baffling, you are just clinging to a legacy bottleneck (NAT) that was never designed to be a security feature
> never designed to be a security feature
It's virtually always used with some firewall rules, so it sort of is? It's just dogma to insist that there are no security benefits to having a single choke point for traffic.
The firewall is what is providing security, not NAT. And you can equally easily have a firewall in front of an IPv6 network.
NAT superceded ipv6 quite plainly, and it is obvious what technology won out.
Er… not at all. NAT and ipv6 are both very widely used, with IPv6 adoption steadily growing over time.
Only due to the mobile device space. It will not take off outside of Wireless telco networks.
Take a look at the IPv6 Google graph that everyone loves so much:
https://www.google.com/intl/en/ipv6/statistics.html
You can clearly see an initial steep spike to the curve where mobile adoption was new and fierce, and then the curve starts slowly becoming less steep over the last 10 years. It will peter out and remain steady when mobile device adoption reaches critical mass.
How do you look at a chart showing Google access is 50% IPv6 and then proclaim that clearly NAT “won out”? In what world is 50% market share a loss?
No, as I pointed out in another reply to you, home internet is commonly dual-stack (at least in the US and many other countries), and machines with dual-stack connectivity can and do use IPv6 to connect to sites that support it. You can verify this yourself using Wireshark or similar tools.
sudo networksetup -setv6off Wi-Fi ; sudo networksetup -setv6off Ethernet
to protect your privacy