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b112last Saturday at 4:21 PM2 repliesview on HN

There are lots of legacy things in tcp/ip headers. One of them can be for the extra octlet.

When ipv4 legacy flies around, that oclet will be null or 0. The entire internet could route just fine, especially if you put the extra octlet at the end. 1.1.1.1 gets an extra 1.1.1.1.newoctlet.

So every existing IP gets a bonus 255 new IPs, and for now, routing of those is hardlocked to that IP, and it works with all legacy gear.

In 30 years or something, we can care about the mobility of those new IPs.


Replies

Ekaroslast Saturday at 5:41 PM

Pray tell me exactly where in the IP packet you put those extra octets. In a way that it affects zero other devices?

Dagger2last Saturday at 5:31 PM

You're at the very beginning, baby steps stage of inventing IPv6 there.

You aren't the first person to come up with the idea of adding extra bits to IP addresses to make them longer. The problem isn't finding somewhere to stash the extra bits in the packet format (which is trivial; you can simply set the next-protocol field to a special value and then put the bits at the start of the payload), it's getting all software to use those extra bits -- and getting that to work requires doing all of the new AF family, new sockaddr struct, new DNS records, dual stack/translation/tunnels etc etc that v6 does.

Please consider that maybe the people working on v6 weren't actually complete imbeciles and did in fact think things through.

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