undefined | Better HN

0 pointstsoukase2mo ago0 comments

Something like 1:2:3:4:a:b:c:d where the most significant 32bits are a valid IPv4. The kernel figures out and keep all others the same (NAT etc). We extend the address space, not invent a new stack. The IPv6 critics shout out that this would be a viable solution.

0 comments

4 comments · 1 top-level

Dagger22mo ago· 3 in thread

Okay, so you've figured out how to make v4 addressable from v8. Good job. That lets v8 hosts address a v4 host via a v8 address.

How are you going to make v8 addressable from v4? Because you need to do this too for communication to work.

Also, you've made v4 addressable from v8, and you're about to explain how you make v8 addressable from v4... but that's just addressing, i.e. identifying the right host. How are you going to actually send packets from v8 to v4, and also from v4 to v8?

> The IPv6 critics shout out that this would be a viable solution.

But they never bother to understand enough of the problem to contribute anything useful. Either they can't come up with something that works, or they come up with something that they didn't realize v6 already did.

tsoukaseOP2mo ago

> How are you going to make v8 addressable from v4?

I expected this question and have thought about it. Here is an idea: all nodes (PCs, routers etc) run an updated stack, which sends/receives 64bit addresses. If it receives 1:2:3:4:0:0:0:0, that's v4 and continues as such. It's on the ISP when the switch happens because they deliver the addresses. The user notices nothing. Edge cases can arise and be handled accordingly.

The update from 32-to-64 will be massively pushed to all kernels and userspaces in a short time so to shorten outages.

lolc2mo ago

At what point could I confidently publish the addresses 1:2:3:4:0:0:0:1 and 1:2:3:4:0:0:0:2 in DNS records for people to reach those two servers? After my ISP has switched, or after everybody's ISP has switched?

The idea that any ISP would do a Dagen H is very alien to how an ISP thinks. https://en.wikipedia.org/wiki/Dagen_H

1 more reply

Dagger22mo ago

So basically, instead of extending the v4 address space you're going to make a new stack and everybody needs to switch to it to be able to communicate with v8. That's the exact thing you said you weren't doing.

> If it receives 1:2:3:4:0:0:0:0, that's v4 and continues as such

1:2:3:4:0:0:0:0 isn't v4, so it can't "continue as v4"... perhaps you meant that a router somewhere converts the packet to a v4 packet, but this is still only the v8->v4 direction. How do you map v8 into v4 so that the destination can reply?

> The update from 32-to-64 will be massively pushed to all kernels and userspaces in a short time so to shorten outages.

Right, add support for the new stack everywhere like we did with v6's 32-to-128 update. But just saying that it'll be done in a short time doesn't mean it will be.

j / k navigate · click thread line to collapse