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Comment by alt227 | Hacker News Reader

IPv6 was superceded by NAT a long time ago.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.

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Oh no, somebody should warn all the ISPs deploying IPv6-native connections with v4 reachable over some fallback technology (464XLAT, DS-Lite, NAT64 etc.) to their hundreds of millions if not billions of customers!

--Sent from my IPv6

The only ISPs issuing IPv6 only connections are mobile device operators and Telcos. THey are a small subset of ISPs in the world and IPv6 only connections will never gain any traction outside of that world.

I agree it will not die so I retract that statement, but it will never fully replace IPv4 in standard wired internet connections.

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.

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.

The legacy of the Ping of Death and redirect abuse still looms over people that may not have been born yet :)

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.

The biggest tangible benefit is you don't need to worry about NAT port mapping any more. Every device can have a public address, and you can have multiple servers exposing services on the same port without a conflict.

(The flip side is having a network-level firewall is more important than ever.)

You also don't have to worry about running a DHCP server anymore, at least on small networks. The simplicity of SLAAC is a breath of fresh air, and removes DHCP as a single point of failure for a network.

Few people care about exposing a server in the first place, even fewer care about multiple servers on a single port.

So the benefit is that you dont need to worry about NAT for a couple of port forwarded services you may use (which might well even use UPnP for auto setup), but the tradeoff is you now need to think about full individual firewall protection for every device on your network?

I'll take full security by default and forward a couple of ports thankyou!

> All of my devices are assigned 4 IPv6 IPs

Loopback, link local and network assigned. What's that problem? Your ipv4 hosts are can reach themselves through millions of addresses already.

> hostnames are replaced by auto assigned stuff from the ISP

Hostnames replaced? IPv6 doesn't do DNS...

> lots of random things don’t work.

Lots of random things also don't work on ipv4. :)

> 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.

It's not the bandwidth it's the latency. Because of the latency you need to pack a small amount of data in VoIP packets so the extra header size of IPv6 stings more than it would for ordinary http traffic

https://www.nojitter.com/telecommunication-technology/ipv6-i...

I have a lot of trouble believing IPv6 matters here. Your link only talks about bandwidth (an extra 8kbps) and doesn’t even mention latency.

Edit: NAT also adds measurable latency. If anything I’d think avoiding NAT might actually make IPv6 lower latency than IPv4 on average.

You can maybe connect to everyone over IPv4, but chances are that that path is strictly worse (in terms of latency, P2P reachability, congestion et.c) than a v6 one would be.

For example, two IPv6 peers can often trivially reach each other even behind firewalls (using UDP hole punching). For NAT, having too restrictive a NAT gateway on either side can easily prevent reachability.

I have tailscale on all my mobile/portable devices I use away from home. It punches holes so I don't have to, even makes DNS work for my tailnet in a way I've never been able to get to work the way I want the normal way.

Yes, Tailscale is great, and it does manage to traverse pretty much every firewall or NAT in my experience as well. Quite often, it even does so using IPv6 :)

Last time I looked at Digital Ocean they had completely missed the purpose of IPv6 and would only assign a droplet a /124 and even then only as a fixed address like they were worried we are going to run out of addresses.

But really what's the point of giving half an internet worth of addresses to every machine? I never understood that part of IPv6.

I think it would have been better having shorter addresses and not waste so many on every endpoint.

Yeah, the current system is really weird, with many address assigning services refusing to create smaller pools. I really hope that's fixed one day. We already got an RFC saying effectively "going back to classful ranges was stupid" https://datatracker.ietf.org/doc/html/rfc6177 (for over a decade...)

Because 2^128 is too big to be reasonably filled even if you give a ip address to every grain of sand. 64 bits is good enough for network routing and 64 bits for the host to auto configure an ip address is a bonus feature. The reason why 64 bits is because it large enough for no collisions with picking a ephemeral random number or and it can fit your 48 bit mac address if you want a consistent number.

With a fixed size host identifier compared to a variable size ipv4 host identifier network renumbering becomes easier. If you separate out the host part of the ip address a network operator can change ip ranges by simply replacing the top 64 bits with prefix translation and other computers can still be routed to with the unique bottom 64 bits in the new ip network.

This is what you do if you start with a clean sheet and design a protocol where you don't need to put address scarcity as the first priority.

Thanks for this. It's pointless to argue, but I wonder if shifting from 32 to 64 bits, instead 128, would have seen faster uptake.

Aside, isn't embedding MAC addrs in ones IP address a bad idea?

Point of fact it's giving 4 billion Internets worth of addresses to every local subnet.

You will sometimes see admins complain that IPv6 demands that you allow ICMP (at least the TOOBIG messages) through the firewall because they're worried that people on the internet will start doing pingscans of their network. This is because they do not understand what 2^64 is.

And won't that allow pingscans?

Do the math on 2^64 possible host addresses, multiply by the length of an IPv6 ICMP ECHOREQUEST, and then divide by available bandwidth to determine how long it might take you to scan a single subnet.

Hint: the ICMPv6 packet is no shorter than 48 bytes and there are 1.8446744e+19 addresses to scan.

"Simple" VPS providers like DigitalOcean, etc. really need to get the hell onboard with network virtualization. It's 2026, I don't want to be dealing with individual hosts just being allocated a damned /64 either. Give me a /48, attach it to a virtual network, let me split it into /64's and attach VM's to it - if I want something other than SLACC addresses (or multiple per VM) then I can deal with manually assigning them.

To be fair, the "big" cloud providers can't seem to figure this shit out, either. It's mind boggling, I'm not saying I've gone through the headache of banging out all the configuration to get FRRouting and my RouterOS gear happily doing the EVPN-VXLAN dance; but I'm also not Amazon, Google, or Microsoft...

Do you think anything other than trivial internal networking is a common requirement on DO? I’m not saying it’s not, I really don’t know— I haven’t been in the production end of things for a while and when I was, everyone was basically using AWS et. al. for non-trivial applications. They make it easy enough to set up a private ipv4 subnet to connect your internal services. Does that not satisfy you use case or are you just avoiding tooling that might be obsolete sooner than ipv6?

I use IPv6 on my authoritative DNS servers and that's basically it. To your point keeping it disabled on all my hobby crap keeps everything simple for me. If someone can not reach IPv4 then something is broken on their end.

IMO ipv6 is a perfect example of why interface designers can be valuable on technical projects. One of the genius things about ipv4 is it’s a pre-chunked number you can shout across the room or keep in your head as you run down the hall to your keyboard. IPv6 addresses simply don’t have that feature. If they had kept the 4-chunk format and made it alphanumeric, or added a chunk and made it hexadecimal, or something along those lines, I think they could have reasonably alleviated the problem of running out of addresses while not making the addresses SO unfriendly to remember.

But when designers bring things like that up, you get “it’s really not that complicated,” or “I explained this to my 200 year old grandmother over tea/my 16 month old child over the course of a diaper change/my non-technical wife that I intellectually respect less than I should/etc. and they wrote a book on it the next day,” kind of crap. Human factors engineering. Ergonomics matter in technical products.

NAT doesn't solve everything, and creates a whole new class of problems that you can just avoid by adopting IPv6 natively. And it's definitely not being ignored at larger companies.

In particular, just off the top of my head...

- T-Mobile US doesn't even assign clients an IPv4 address anymore. Their entire network is IPv6 native.

- Many cloud providers charge extra for IPv4 addresses, but give IPv6 addresses out for free.

For trivial cases NAT is easy, for complex situations it's a nightmare. I've been fighting a lonely battle against multiple-NAT VPNs as being the solution to the wrong problem for longer than I care to remember, and I'm tired boss. A few years ago we had a client site go offline because a local network guy just didn't like IPv6 and turned it off, not realizing that a huge amount of stuff was happening automatically and that's why he hadn't been needing to work on it.

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.

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

GitHub only has IPv4 addresses, for instance :-/

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.

That's a bit like saying AC electricity was just a fancy way of delivering what customers really wanted, DC energy.

I'm sure that DC customers used their Edison DC equipment for decades after the grid went AC only; but in the long run the newer, flexible, lower overhead system became the default for new equipment and the compatibility cludges were abandoned.

High voltage AC actually gives more overhead than the same voltage DC.

HVDC is enormously expensive even today and completely impractical for bulk transport 100 years ago. You can't look just at corona, capacitive etc. losses of HVAC, you need to factor in the entire economic equation. The total overhead of AC (cost of equipment + energy lost for the lifetime of the line) is still lower for overground transport over reasonable distances and will remain so for the foreseeable future.

I don't think they even had a way to do dc-dc voltage step-up and step-down at high power and efficiency, needed semiconductors for that to do high speed switching in buck and boost converters

Well, yes. Except that AC came to dominance much faster than IPv6, the AC/DC war lasted less than 10 years, with the AC quickly coming to domination. Because AC provides a clear performance advantage over DC.

This is not really true of IPv6. It _still_ has tons of actual operational issues, and in the best case, it does not provide any tangible improvements over IPv4+NAT for the vast majority of users.

For example, in-flight entertainment works by assigning you an IPv4 address and allowlisting it in the gateway rules. This does not work with IPv6 because of privacy addresses and SLAAC. You might think that you just need to do stateful DHCPv6, but Android doesn't support it. Heck, even simple DHCPv6 PD automatic configuration is _still_ not a standard ( https://datatracker.ietf.org/doc/rfc9762/ )!

So to this day, some of the most visited sites like amazon.com, ebay.com, tiktok.com, slack.com or even github.com do not support IPv6. I also keep providing this example, year after year: there are no public VoIP SIP providers in the US that simply _support_ IPv6. Go on, try to find one.

Yep, mobile device space ISPs again which is what keeps being argued. IPv6 only connections will never gain full traction outside of the mobile marketplace.

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.

> So… the largest ISPs.

Yep, a few gatekeepers of a single device space.

Your numbers are wrong, seee the google graph everybody is pointing to:

https://www.google.com/intl/en/ipv6/statistics.html

Name a large isp not using V6

They are all using IPv6.

Name one which has stopped using IPv4.

Goalposts -> thataway.

Maybe in the US. I've seen IPv6-only connections via DS-Lite in more than one other country on wired home ISPs.

AWS charges for ipv4 addresses but ipv6 addresses are free. ipv4 with NAT doesn't supercede ipv6, it just extends its life.

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.

Matter/Thread use private IPv6 addresses so it's just an implementation detail. Nobody is exposing light switches to the public Internet.

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

> 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

More IPv6 deployments may (ironically?) help reduce IPv4 prices as you can get IPv6 'for free' and have Internet connectivity (and not have to worry about exhaustion in any practical way). Doing CG-NAT could reduce the number IPv4 addresses you need to acquire.

IPv4 addresses are basically free - indeed they are a profit centre. At $20 an address that’s $2 a year at most (10% ROI) where many charge 20 times that ($5/month isn’t unheard of)

NAT fixes it in the sense that blocks become available when providers switch to CGNAT.

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.

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.

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?

The trend on that graph is slowing, and when we reach criticl mass on the number of mobile devices the graph will be flat.

There is no chance we will be at 95% usage in 5 years or so.

If you like, we can make a wager?

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=...

Wow, billions of devices per country and they have still only reached 50%.

Damn, the jealousy (?) is palpable. You know you will have literally zero impact on adoption no matter how snarky you are, right?

Jealousy? I think you may need to expand your vocabulary a bit!

I have an opinion on something, I assume thats ok? You seem to be here trying to prove me wrong, and also commenting on my tone of reply.

Im not trying to tell you that you are wrong, only stating what I think. If you dont like my opinion, feel free to ignore it. You are not forced to comment.

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.

Apologies maybe slow death was the wrong phrase. I did mean that, but only in the non-mobile space. Obviously mobile device networks have made good use of IPv6 and will continue to.

However In another thread it was argued that when IPv4 addresses become very expensive, that could trigger a big shift to IPv6. I agree with this statement and so IMO it is possible that IPv6 may well become ubiquitous in the future.

When usage is increasing rapidly and is literally ~ 50% of the entire planet right now, how is ANY kind of 'death' a useful descriptor?

IPv4 is the one that descriptor belongs on, eh?

No I dont agree at all.

Usage is in no way 'rapidly increasing', in fact the google graph everyone is touting around shows that it has taken over 10 years to not even get to 50%. It also shows it is slowing down, the curve is starting to become less steep.

When Maximum possible IPv6 usage is not even at 50% after over a decade and the usage curve is slowing, how can you possibly say that IPv4 is dying and IPv6 usage is rapidly increasing?

Oh, now it’s a problem because it’s been about a decade?

So what, another decade and we should be mostly done?

What do you think is a reasonable amount of time to redo the entire world’s networking infrastructure across 200+ countries and 8 something billion people, exactly?

This is an absurd argument, you know that right?

> Oh, now it’s a problem because it’s been about a decade?

No, but taking over a decade to not even be half adopted does not count as rapid in my opinion.

> So what, another decade and we should be mostly done?

No, as I have said many many times, the graph is slowing.

> What do you think is a reasonable amount of time to redo the entire world’s networking infrastructure

We dont need to, thats the point. All networking equipment in the world already supports IPv6, so why isnt it at 100% usage and IPv4 is turned off already?

>This is an absurd argument, you know that right?

Who is the fool, the person saying what they think or the person continuing to participate in an argument they consider absurd?

You dont need to make everybody in the world agree with what you are saying, it is ok to have differing opinions. You know that right?

I am done now. I accept that you disagree with me and thats fine. Can you afford the same decency or will you continue to tell me I'm wrong?

Hahahahaha

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.

Yep, every ISP and every device supports IPv6 and has done for ages.

Show me one where they have disabled IPv4 and only use IPv6 that is not a mobile device or Telco ISP.

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.

Yes good point, I agree that IPv4 addresses are going to become a commodity in the future and their value will start to increase dramatically to the point where it is only corporations which can afford to use them. IPv6 use may well start to spike again if that happens.

It was simply to point out that you are objectively incorrect. No commentary was necessary. My phone and home broadband both use IPv6 primarily.

If you were correct, that graph would have been over 50% ages ago.

As it is, that graph is showing how adoption is slowing and has been for the last 10 years.

Hardly anybodies physical internet connection is using IPv6 primarily worldwide, those numbers are all mobile device space.

> Over time you will see that graph flatline and peter out as mobile device uage reaches critical mass.

...what? The majority of people access the Internet from their phone, and not only since yesterday either. Are you arguing that this is temporary fad somehow?

I don't think they are arguing for a decrease. I took flatline and peter out to mean stabilize.

That is correct, thankyou for assuming the positive instead of the negative.

I personally believe that at about 60% utilisation the line on the graph will become flat and stay that way.

I am arguing that at some point there wont be any more people without phones, meaning it has reached critical mass and so IPv6 adoption will stall. The number of smartphones in the world will not keep on going up forever.

That would only happen if all of v6's growth is coming from mobile users, no mobile networks are growing/deployed without v6, and also no users are dropping their wired connections.

You can look at the AS breakdowns on APNIC's stats and see that ASs that serve non-mobile customers are getting v6, and that some ASs for mobile users aren't. So no, it won't stall.

Slow down perhaps, but it has to slow down at some point or it'll go above 100%.

What is the source of the seasonality in that graph? Spikes up a little each summer.

Maybe iPhone release time?!

If that is the case then why does it drop in absolute terms later in the year?

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