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The IPv6 Transition

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Re: The IPv6 Transition

#381

Post by matrix2003 »

vetinari wrote: post #238
matrix2003 wrote: post #188

Earlier quoted context omitted.

Why do dynamic address allocations matter? Most IPv4 consumer WAN addresses are also dynamic. I’m asking, because I’m an advocate of having your gateway advertise a separate, stable ULA /64 in conjunction with the globally-routable dynamic /64. This gives you a stable set of addressable LAN IPs, and you can usually ignore the dynamic globally routable IPs. Granted this won’t work for everyone, but if dynamic global a…

It matters, because when the prefix changes, it changes IP addresses of every single device in your network. As you wrote, internally, you can use ULA. But you cannot open access from outside, because your firewall rules will become invalid with prefix change. With classic IPv4 NAT, your internal addresses don't change, so your port forwarding works, even if the WAN address changes. Together, with a single /64 -- whi…

Could you NAT the router WAN external address and route it to a static ULA?

I think the more elegant solution is to use static IP space for hosting services, but most of us home users aren’t used to that.

Re: The IPv6 Transition

#382

Post by matrix2003 »

preisschild wrote: post #240
matrix2003 wrote: post #188

Earlier quoted context omitted.

Why do dynamic address allocations matter? Most IPv4 consumer WAN addresses are also dynamic. I’m asking, because I’m an advocate of having your gateway advertise a separate, stable ULA /64 in conjunction with the globally-routable dynamic /64. This gives you a stable set of addressable LAN IPs, and you can usually ignore the dynamic globally routable IPs. Granted this won’t work for everyone, but if dynamic global a…

Having an extra 1:1 ipv6 NAT for ULA is added complexity that wouldn't be neccessary if you just give out static addresses. Its not like IPv6 /56 subnets are expansive. Just give each customer a full /56 net and you are done.

I think the OC was arguing that if your global /64 changes, the firewall rules would change as well for any hosted services.

I proposed that you might be able to route the external router’s WAN to a ULA via NAT to save in complexity when the PD changes, but I agree that a static delegation would by far be the easiest. Us home hosters aren’t used to that even though it is technically against the license agreement more often than not.

Re: The IPv6 Transition

#383

Post by cyberax »

elcritch wrote: post #377
cyberax wrote: post #358

Earlier quoted context omitted.

> I'd use hostnames in either case How? There is no way to associate hostnames with addresses in IPv6 that works unversally. Stateful IPv6 is _not_ _supported_ by Android, for example. And since _each_ _device_ handles its own address selection, there's no central way to say "hey, this is an IP camera, let it have a static ::1:2:3:4 address suffix". Moreover, with IPv6 I'm losing an ability to do quick checks of the…

> How? There is no way to associate hostnames with addresses in IPv6 that works unversally. It looks like SLAAC and RDNSS is supported by most modern OSes, including android. It’s definitely much more painful currently, but no reason you couldn’t have your router broadcast RDNSS. Then in your routers local DNS registry associate IP camera at ::aac::eda3::1 to ‘ip-camera-1.internal’. In theory about as easy as configu…

RDNSS is simply a DNS server name, it doesn't do anything for the reverse process (host-to-server registration).

> Then in your routers local DNS registry associate IP camera at ::aac::eda3::1 to ‘ip-camera-1.internal’. In theory about as easy as configuring device at Mac ‘de:fe:34:21:00’ is set to IP 10.0.0.5 and host name.

I don't see how it works. RDNSS is purely unidirectional and doesn't affect the assigned IPv6 addresses.

Re: The IPv6 Transition

#384

Post by josephg »

selcuka wrote: post #375
josephg wrote: post #194

Earlier quoted context omitted.

> IPv4 exhaustion is a real problem, it's just not enough to motivate people much. Well, its only really a problem if you're poor. Rich people don't care - IPs are still cheap enough when you live in a wealthy country & have a decent job. The people affected by IP address exhaustion are largely the exact set of people who can't do anything about it.

Remember rich people wants to sell stuff to poor people, so if it's a problem for poor people then it's also a problem for the rich.

True. But CG-NAT is mostly fine for disempowered consumers.

Re: The IPv6 Transition

#385

Post by kevvok »

AStonesThrow wrote: post #349
kevvok wrote: post #236

Earlier quoted context omitted.

According to the IANA assignment list, 2600::/12 is assognrd to ARIN. https://www.iana.org/assignments/ipv6-unicast-address-assign...

Yes, that's correct -- I'm in the USA, and not in Europe or Africa. What is your point with this? ARIN has, of course, delegated my assigned IPv6 network to my ISP; you do realize that this is SOP for ARIN?

The point was a prefix from 2600::/16 isn’t special; it’s just from one of the blocks assigned to ARIN. One ISP I know of with an allocation in that range is Verizon, which announces a number of prefixes over BGP in 2600:1000::/24

Re: The IPv6 Transition

#386

Post by AStonesThrow »

kevvok wrote: post #385
AStonesThrow wrote: post #349

Earlier quoted context omitted.

Yes, that's correct -- I'm in the USA, and not in Europe or Africa. What is your point with this? ARIN has, of course, delegated my assigned IPv6 network to my ISP; you do realize that this is SOP for ARIN?

The point was a prefix from 2600::/16 isn’t special; it’s just from one of the blocks assigned to ARIN. One ISP I know of with an allocation in that range is Verizon, which announces a number of prefixes over BGP in 2600:1000::/24

Uhm, anyone with an ISP in the United States is going to have a block delegated from ARIN. That's the whole point of ARIN, isn't it? Nothing they delegate is inherently special, because ARIN administers all of the allocations for their region.

I'm saying that perhaps the 2600::/16 delegation is especially reserved for a certain class of user in order to tag us as something. Surely, my own ISP holds more delegations than that slice alone. It's certainly standing out like a sore thumb to anyone analyzing logs. As I said, it can't be merely a coincidence.

Interestingly, I also subscribe to mobile voice/data service from the same ISP, and activating mobile data here at home gives me, sure enough, another 2600::* delegation.

Re: The IPv6 Transition

#387

Post by kortilla »

tialaramex wrote: post #152
kortilla wrote: post #65

Earlier quoted context omitted.

> Anyone willing to place a bet on this? Ill bet against it. The tail on this one is going to be super long. There are embedded systems today that are shipping in things expected to last 30 years with IPv4 only. The logistics of the bet are going to be hard. I do see a world where IPv6-only becomes the default for ISPs and IPv4 becomes an add-on you pay for either from your ISP or from another via a tunnel. Does that…

The long tail doesn't matter. Once IPv4 traffic is a small fraction, the big transit providers will make it cost too much to bother with, and their customers (retail ISPs) will just cut it. Only global IPv4 matters. If in fifty years there's still a device that insists on speaking IPv4 with the address 10.20.30.40 that will still work and it still won't matter to the Internet any more than it does now. The appropriat…

> The long tail doesn't matter.

We’re talking about the logistics of a bet, it’s the only thing that matters in this context.

The big transit providers pay very little to carry ipv4 prefixes. They will never even consider cutting it as long as there are any semi large content providers offering v4. Transit cores are prefix-free with segment routing so the cost is basically just the device that peers at the exchanges with other peers.

> The appropriate comparison is leaded gasoline.

It is not. The price dynamics make it so cheap to keep supporting ipv4 that it’s nothing like the unleaded switch. That’s before you even consider how dumb “banning the sale of new IPv4 devices” is.

Re: The IPv6 Transition

#388

Post by kortilla »

agubelu wrote: post #114
kortilla wrote: post #80

Earlier quoted context omitted.

Seat belts have a reason. If I want to communicate with some computers using IPv4 or IPX, that’s my choice. Putting laws on what I can put inside of Ethernet is absolute stupidity

I fail to see how mandating ISPs to implement and use IPv6 is equivalent to "putting laws on what you can put inside of Ethernet"

Maybe don’t talk about stuff you don’t have any experience with then. Many ISP products are carrying Ethernet frames (metro Ethernet, the fabric at an exchange) or are even just leasing fiber.

In order to force IPv6 and ensure nobody is using IPv4, you absolutely are putting laws on what goes over those Ethernet frames.

Re: The IPv6 Transition

#389

Post by nikanj »

growse wrote: post #98
nikanj wrote: post #62

Earlier quoted context omitted.

Serious, competent network engineers are not created in vacuum from platonic ideals and TCP fragments. They're home hobbyists who grew up hating ipv6, and won't magically learn it overnight when their previous networking guy quits and they get handed the keys to the server cage

These people are neither competent nor serious. In the real world, people who design and operate large networks are the very same people who staffed the working groups who designed IPv6. It's their design.

"IPv6 is great and easy to use, if you're one of the leading experts who designed it"

This is not the kind of glowing endorsement you think it is, if you're expecting your technology to see widespread adoption

Re: The IPv6 Transition

#390

Post by znpy »

iam-TJ wrote: post #264
NelsonMinar wrote: post #122

Earlier quoted context omitted.

Starlink uses CGNAT. It's awful, I'm regularly getting CAPTCHAs on random websites. They now support IPv6 but only with dynamic address allocations so you don't get a lot of advantages from it.

I've been using Starlink since early 2021 with IPv6 only internally. Starlink User Terminal hands out a /56 prefix (via DHCPv6) and mine has not changed in all that time so I wouldn't call it dynamic. The User Terminal issues a router advertisement (RA) and my gateway gives itself an address in that /64 via SLAAC in addition to assigning itself an address from the /56 prefix. If not using prefix delegation each host'…

> Starlink User Terminal hands out a /56 prefix (via DHCPv6) and mine has not changed in all that time so I wouldn't call it dynamic.

Unless the service explicitly states that your subnet is your or yours alone you should assume it's dynamic.

If you start relying on the prefix not ever changing you might have a bad surprise.

And from experience, that kind of surprises always come when you least need them.

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