* https://havevirginmediaenabledipv6yet.co.uk/
A major ISP in the U.K., that said in a public statement on World IPv6 Day in 2011 that
> As well as our core and access networks being capable of supporting IPv6, we're rigorously testing our entire network to ensure that all customers have a smooth and simple transition when the time comes to flick the switch and turn IPv6 on. We're really pleased with how our tests are advancing and are happy to say that by the end of 2012, we'll be able to fully support customers looking to switch to IPv6.
has not managed to actually flick that switch in 15 years.
* https://ispreview.co.uk/story/2011/06/08/uk-isp-fluidata-hai...
1. Sites that help shoppers choose can add a big visual red flag to any ISP that doesn’t support IPv6. Consumers don’t know what IPv6 is by and large but they do understand seeing a big red flag.
2. Same thing for websites. Add a banner that says “hey your ISP doesn’t support proper internet connectivity which this site utilizes. Contact them to let them know that you are having internet issues.” Again, consumers do not know what’s IPv6 is, but they do know what annoying banners are.
(It’s true that you can use cellular for your home internet, but I consider that extremely compromised.)
As far as IPv6, both provide it, but after running with IPv6 on AT&T for about a year, I disabled it because whenever I had a rare random connection issue, I never knew whether IPv6 was the culprit and it was one less variable to debug.
This is one of those “if everyone just” solutions that doesn’t work because shopping websites would never do that. Amazon has tons of evidence that even the slightest bits of friction result in noticeable drops in sales.
I don't think I bothered asking them again!!
(Edit "them" = Virgin Media)
But the way that they dealt with the whole thing smelt very "we don't know what we're talking about", enough to put us off.
And shifting all the IP space about would have had costs with very little return, so little business appetite to go through it.
That plus other ISPs v6 implementations breaking things randomly, I understand why they don't bother.
This has taken pressure off the IPv4 legacy address pool, reducing the urgency for older providers.
End-users are typically completely unaware of whether their traffic is being carried over IPv6 or IPv4, and so simply do not care one way or the other. (This particular post is more than likely being made over IPv6, since news.ycombinator.com has an IPv6 address and my OS, browser, router and ISP all support IPv6 straight out of the box, as is now true for the majority of users in my country.)
IPv6 not being supported in many places means the internet is more centralised, less likely to use proper p2p tech- because it's a lot harder to make it work rather than throwing up a TURN box and relaying everything.
"The latency? Who cares? IPv6 sometimes breaks right now" - because nobody is testing it, so why should people be the first to support it? There's no easy upside.
The only real upside for businesses is not having to pay for increasingly expensive IPv4 allocations. But they don't really care, its not nearly expensive enough yet. Customers will get GCNAT, businesses will continue as normal.
All that will happen is that the internet gets slower and less equal.
Which is exactly the same thing that's happening with inefficient memory hungry software: people either have to buy a more expensive laptop or they have a shitty experience.. Nobody is advocating for them, they just feel things getting shittier year on year and many are just choosing to avoid technology instead.
Realistically nobody outside some devoted HN readers are going to self host their own content. At best you'd see something like netflix trying to offload their video hosting costs onto their customers.
bittorent has been around for decades and nobody used it. They emailed files to themselves instead, or used dropbox. This all happened before the ipv4 shortage and people getting moved to CGNAT.
no reason this has to be centralised.
in fact, Jitsi uses p2p with WebRTC until a third person joins the call: then migrates the call to be relayed.
A really nice latency win.
ISPs had/have whole groups trying to stomp it out.
And it was a nightmare due to NAT even then.
It just got worse with CGNAT.
Even Linux distros push you so direct downloads now rather than pointing to trackers.
BitTorrent only has healthy usage for content that’s untenable to host legitimately.
Also, hey now - I have a lot of (actual) Linux disk images, and it works well for that!
It's almost always faster than anything else available, and ipv6 would make that method of sending files closer to the default for most people.
Having VOIP in games or 1v1 lobbies is, in the strictest sense, "hosting" something in the same way.
FD: I work in video games so I speak from this bias.
Isn't self hosting, and small, private/semi-private communities the only way forwards for much of the internet? AI has made content extremely valuable, which in turn has started to destroy the openness of the web. Things are getting more and more siloed, with entry fees.
There's a world where self hosting comes back in a big way. AI ironically makes it much easier.
How about Xbox/PS multiplayer/P2P gaming? Hosting a Minecraft server?
When Skype first came out it was P2P, but had to come up with the "supernode" concept (basically STUN/TURN/ICE) because of NAT: now all of our communication methods basically have to phone into the mothership.
Do we want the Internet to be more centralized (possibly given more power to the tech bros) or more decentralized?
So p2p stuff still doesn’t work without explicit configuration that rules out 99% of your users. It’s super annoying.
It's a shame because if we could only get over stateful firewalling we'd be one step closer to the impossible task of using voice chat in console video games.
Right now they don't have that of course and the only hurdle is "NAT Types" which, as we all know, is a much easier problem to solve for the average person...
(this was sarcasm, if it wasn't clear).
If I'm with a small-time ISP that has to use CG-NAT because they don't have the cash to buy/lease enough IPv4 addresses to give one to each CPE WAN interface, then using things like Xbox/PS multiplayer/P2P gaming is no longer possible. Want to host a Minecraft server? Too bad.
Are those two use-cases "useful to the consumer"?
It wasn't meaningfully more difficult than setting up the server.
It’s gotten much worse.
It also just reduces resource waste (of labor time). Countries like China that have insufficient IPv4 addresses and political power have mandated it. One IP per home is manageable, for now, but CGNAT is really bad.
The reason to regulate in maybe 2000 or so was that staying with IPv4 led to NAT. NAT led to it being impossible for users to receive incoming connections. Inability to receive incoming connections led to (a) horrendous protocol complexity, (b) probably some applications never even being invented, and, (c) everybody using ultra-centralized services. Ultra-centralized services led to advertising-driven distortions of service utility, concentration of political and economic power, and choke points. Choke points led to surveillance state bullshit that's just fully ripening today.
And, yes, this was (in broad outline) foreseeable in 2000. I wasn't the only one.
It's Optimum Communications and Frontier (my provider) that are really holding the numbers down at ~15% each. The latter is improving very slowly, but not a lot of evidence of change in the former.
Their core network has IPv6, but not their customers, 17% market share in telecom in the Netherlands.
Are there more?
PS: From the millions of customers' details leaked it sounds like their market share is a hell of a lot higher than 17%!
Virgin Media exist for two reasons: first they were given a monopoly by their Tory chums (Thatcher) and, second, all ISPs are allowed to make you sign absurdly long, anti-competitive contracts (18 months is common). If ISPs were treated the same as utility suppliers we'd probably be in a better place.
IPv6 traffic crosses the 50% mark - https://news.ycombinator.com/item?id=47777894 - April 2026 (621 comments)
---
Other recent threads, if anyone would like a thousand more IPv6 comments:
The world in which IPv6 was a good design (2017) - https://news.ycombinator.com/item?id=47821429 - April 2026 (166 comments)
IPv6 is the only way forward - https://news.ycombinator.com/item?id=47680124 - April 2026 (339 comments)
IPv6 Adoption in 2026 - https://news.ycombinator.com/item?id=47083086 - Feb 2026 (21 comments)
IPv6 is not insecure because it lacks a NAT - https://news.ycombinator.com/item?id=46696303 - Jan 2026 (577 comments)
Good example of the 2020s on why there is practically truly only one Internet instead of many.
But simply it is impossible to go full ipv6, as many of isps of the clients do not support it.
Currently there is no pressure to the isps to move to ipv6. In fact the incentives are OPPOSITE! They love charging for static IPs.
My company has just turned off all ip6 connectivity for its corporate laptops because it’s considered a security risk. I disagree, but I do agree that having 4 and 6 is a higher risk than 4 alone or 6 alone, and 6 alone sadly still doesn’t work reliably.
All the “promise” of ip6, direct connections etc, were lost when stateful firewalls became required and memory became cheaper than $20 a megabyte. Some bespoke old protocols don’t like ports changing, which can be a problem, but it’s a very small number and easier to work around with modern protocols than support a dual stack environment securely for the majority of places that struggle securing a single stack.
If your corporate laptops are running Windows, then you're going against the officially supported configuration of the vendor (Microsoft):
> Internet Protocol version 6 (IPv6) is a mandatory part of Windows Vista and Windows Server 2008 and newer versions.
> We don't recommend that you disable IPv6 or IPv6 components or unbind IPv6 from interfaces. If you do, some Windows components might not function.
* https://learn.microsoft.com/en-us/troubleshoot/windows-serve...
> Cg nat does everything that’s needed […]
Except for making it convenient for end-user to, say, play P2P video games, or host Mindcraft servers, etc.
> […] and 6 alone sadly still doesn’t work reliably.
It's so unreliable that half of all Internet traffic uses it. It's so unreliable that Microsoft has been going IPv6-only in their corporate networks (a decade ago):
* https://labs.ripe.net/author/mirjam/ipv6-only-at-microsoft/
It's so unreliable that Google is now 99% IPv6-only/mostly on their corporate networks:
With ipv4 you have a two tier internet. Computers talk to servers, servers talk to servers, computers can't talk to computers so every video call must be routed through a server.
That the server can figure out that two computers in the same house are different since your laptop and phone no longer share the same ipv4 address but instead have two ipv6 address?
Your phone and laptop can just have multiple ipv6 addresses and rotate through them regularly... as apple does by default https://support.apple.com/en-ca/guide/security/seccb625dcd9/...
Security? NAT is not a firewall, you need a firewall, and switching to IPv6 does not remove your firewall.
Before IPv6: The server gets "1.2.3.4:56789" for your device. After IPv6: the server gets "1:2:3:4::56" or whatever for your device. In either case, if the server makes a connection to 1.2.3.4:56789 or 1:2:3:4::56, your router sees the packet and firewalls the connection. Cool.
Want to give me a concrete example of where IPv6 is hurting my privacy or security, because I've been using it for over a decade with zero mishaps, zero privacy issues, zero security issues (to my knowledge at least)
I've only read that on HN, I've never heard this anywhere else. Since it's been a good 20+ years since my CCNA (and haven't needed to renew it since), could you please offer a real-world example where NAT is not a firewall w/ practical examples relating to 99.9% of cases of home use? I just can't get why people say this a lot here.
NAT works and passes the grandma test. If grandma buys a crappy vulnerable 40$ printer and plugs it in, even if it accepts unauthenticated stuff on every local port, you will not be able to connect to it behind NAT. So what's the difference? The only way I could think this can apply is if the ISP is compromised or criminally mismanaged, in which case you probably already have bigger problems.
But why would you rather have an always-broken network that might block attackers instead of a deliberate "deny incoming" rule that does exactly what you want -- and that you can punch holes in if desired?
Instead we have apps circumventing this accidental barrier with STUN, uPNP, etc with little/no oversight and we also regularly encounter brokenness.
Using a random address (Privacy Extensions) solves this problem though, but do we expect everyone to know what that is and check it's enabled? Mine wasn't enabled by default (on Linux) and I only noticed when a bittorrent site warned me.
* https://support.apple.com/en-ca/guide/security/seccb625dcd9/...
As does Windows (since Vista), and Android (8+).
So why are we still talking about this?
(All of that hinges on the key question that people seldom ask: what is being protected, and from who. The "two-tier" Internet is, in a way, pointing out a case where regular users are seen as threat actors.)
Some people will mention stateful firewalls. They're pretty easy to holepunch through because you just need each side to send a packet to the other, then each firewall sees it as an outgoing connection and allows it. It's nothing like IPv4 NAT.
For example here is how to achieve the same result in PF, note the single additional operator needed to specify nat.
block in on $EXT_IF
#NAT
pass in on $INT_IF to any rdr-to $EXT_IF
#statefullfirewall
pass in on $INT_IF to any
I had a very concreteish security risk with IPv6 and openvpn. At least in Debian config openvpn tunneled only IPv4 by default. I only noticed this by being surprised I got results tailored to my origin country instead of the VPN out node country.
It's eternal (dual stack) paper cuts like this why just turning IPv6 off makes life a lot easier.
Ubiquity gateways also seem to not support it sadly. It would be awesome if they supported something like Hurricane Electric’s tunneling.
$ curl -v https://news.ycombinator.com
* Host news.ycombinator.com:443 was resolved.
* IPv6: 2606:7100:1:67::26
* IPv4: 209.216.230.207
* Trying [2606:7100:1:67::26]:443...
* ALPN: curl offers h2,http/1.1
* TLSv1.3 (OUT), TLS handshake, Client hello (1):
HE tunnel IP space is now sufficiently penalized as non-residential/office that I’ve had to turn it off anyway. YouTube, for example, largely seems to block users in HE space unless they are logged in, and I frequently ran into neverending captchas.
While T-Mobile US has been IPv6-only since ~2018:
But you can't use HE tunnels because every website you visit will block you. You also can't use them from CGNAT or if your home router doesn't have a DMZ.
Is there a law mandating this?
I forgot one detail: your ISP could pay a different tier-1 ISP, as they all interconnect. Nonetheless, your ISP pays top rates for that traffic - tier-1 routes are usually last-resort routes.
Obviously if the ISP is buying transit from HE, they'd have to pay for it, but it'd be surprising if HE was strongarming their customers by adding a clause that's like "oh also, if any of your customers use our ipv6 tunnel, we'll charge you $x/user/month" or whatever.
All my packets go through Seattle, using a Seattle tunnel server adds negligble latency.
But as someone else said, being connected with an he.net tunnel gets you marked as undesirable traffic these days, so that's annoying.
Put all work into reorg, for what? Some numbers to change? Why when IPv4 works?
The real security risk is thinking that just because you have an internal RFC 1918 address space your security has improved.
It's been a decade+ since a firewall being considered a castle/moat of security being best practice. Any IT person that thinks that if they see a device with an 10/8 (or 172.16/12 or 192.168/16) IP and think you're safe you should be fired: it's lazy thinking.
At least if you had a GUA address it would force you to pay more attention to the rest of your security controls. Just recently a co-worker retired some systems that were accessible to the outside via DNAT—but forget to clean up the firewall rules. So he then—for some fucking stupid reason—decided to re-use those same IPs, even though we had so many fucking other IPs available, and one of the boxes got compromised because it happened to have a simple, guessable password on the initial image install.
The bigger issues is not remembering hostnames vs IP addresses.
Unless you have explicitly changed it what is the hostname of your mobile device? How about your PC?
The reality is with an even mildly competent DNS+DHCP implementation that is all you would need...
And mDNS otherwise but it seems only Apple ever bothered with that being default.
I've never seen this chart before, was taking a peek from the link in the article. Does anyone with networking knowledge know why IPv6 usage peaks on Saturdays and dips during the middle of the week? (something related to mobile ISPs?)
But my TP-Link router blocks by default inbound IPv6 connections, without any option to configure it, still bad for pure IPv6 bidirectional streaming, gaming or services on home networks.
I selfhost web and email over my Wireguard VPN using a free VPS (at OCI but I did it with AWS Lightsail too, though it wasn't free but cheap). This can work for you too or you can use easier to configure solutions like Tailscale. This way, your home isn't exposed directly to the Internet.
To your point, IPv6 sought to replace NAT with just having enough addresses but interestingly, that created a problem. If you used NAT and had a service on your computer request a port for incoming connections, that showed intent on behalf of the owner of that service. IPv6 doesn't have that intent, which forces home router makers do block addresses by default because you don't want most PCs on the Internet such that an external agent can scan your PC. You may end up with an unintended service on the open Internet.
So is the bigger address range better? Technically, maybe? But you have to consider defaults and intents of users. And that can take a good technical solution to a bad solution or at least create a whole bunch of problems.
Using NAT as a firewall might work but it brings it's own problems. I find the IPv6 way better.
Glad to hear that you don't have a problem with your router, but how does that relate to GPs problems with theirs?
The solution for them is "get a better router" because the problem is not the IPv6 protocol. Opening a port is not harder than creating a NAT forwarding and if your hardware can't do it then it's bad.
Nobody includes their MAC address in their public IPv6 addresses anymore, but every IPv6 setup that I've seen still gives every device a unique globally-routable IPv6 address, with no NAT at all.
> One of my favorite is the decision to default to /64 blocks.
The nice thing is that a /64 is big enough that clients can just randomly pick any address, and it will almost certainly be available, meaning that you don't need DHCP. This is actually widely implemented, and is known as SLAAC [0].
> Yet we're still stuck with the 128 bit addresses that came from that.
The extra address space only adds 16 bytes to every packet, and it ensures that we will never run out of addresses like we did with IPv4.
[0]: https://en.wikipedia.org/wiki/IPv6#Stateless_address_autocon...
Crucially though, if we change it, we just have to change how addresses are allocated, not change the protocol again.
Yup, and only less than an eighth of the total IPv6 address space has been allocated [0] [1], so there's still plenty of room to expand, even if we have to throw every current address out and start from scratch.
[0]: https://www.iana.org/assignments/ipv6-address-space/ipv6-add...
[1]: https://datatracker.ietf.org/doc/html/rfc3513#section-4
Mine all have link-local addresses (I do have a real static IPv6 address block from my ISP, at great expense…) - so I’m not sure what I did wrong in my Ubiquiti gear.
Picking a random local address (which is very important for privacy, as you've mentioned) is much easier if you don't have to do an elaborate dance of listen, announce, listen for collisions etc. first (practically that still happens, but collisions are the absolute exception).
> So is the bigger address range better?
Yes, because consider the alternative of re-doing all of this again in a future in which IP usage for some reason jumps by a few orders of magnitude again.
Due to hardware getting better over time, the per-packet cost of a few extra bits is going down all the time, while the cost of rolling out a future IPv7 increases with every new deployed host.
Some ISPs are reportedly giving out a /128, and SLAAC works adequately with a router performing IPv6 NAT, so those ISPs don't see a problem.
Mobile phone as WiFi access point is another common way people access the net nowadays. I've occasionally seen permanent installations, with a phone taped to a window. I've never seen a mobile phone AP offer IPv6 to clients, but if they do they have to use SLAAC-compatible IPv6 NAT in that situation.
Randomizing the local address doesn't mean it isn't useful. You can't scan a /64 so that's already a major improvement. The fact that randomly selecting a number is effectively never going to collide greatly simplifies automatic network configuration.
The major issue is that the /64 isn't mandatory from a technical perspective. Being merely a subset of the larger address it's nothing more than a convention. In the end not all providers make it available to you even though supposedly they ought to.
If we're going to complain about anything it should be the godawful notation that so easily breaks parsers. Or the fact that the width is massively excessive which creates a usability nightmare due to normal humans not being able to readily recall 128 bit numbers (let alone how long it takes to type them in).
Every residential router already has PCP (RFC 6887) and UPnP IGD to deal with the NAT44 non-sense that is the status quo, and both protocols support IPv6 hole punching, so IPv6 default deny as a policy is hardly an issue in the residential space.
MiniUPnPd, which many Linux-based CPEs use, has supported IGDv2 (needed for IPv6) since 2012 (as well as PCP).
https://radar.cloudflare.com/adoption-and-usage#ipv4-vs-ipv6
But we have to remember that this reflects the adoption on the client side. With many high profile services still IPv4-only, the fraction of IPv6 flowing on the public Internet might be much lower.
I wonder what incentives are needed to push this forward, because it's not the same incentives as years ago for sure. We've long since exhausted new IPv4 allocations.