nanog mailing list archives
Re: Waste will kill ipv6 too
From: valdis.kletnieks () vt edu
Date: Thu, 28 Dec 2017 20:56:18 -0500
On Thu, 28 Dec 2017 14:14:06 -0500, bzs () theworld com said:
My wild guess is if we'd just waited a little bit longer to formalize IPng we'd've more seriously considered variable length addressing with a byte indicating how many octets in the address even if only 2 lengths were immediately implemented (4 and 16.)
Actually, that got heaved over the side fairly early in the IPng discussion, because nobody who was building silicon last century wanted to deal with arbitrary-length addresses. The IPv4 header had source and destination addresses on 4-byte boundaries for good reasons which still held true when we did the IPv6 headers. And "even if only 2 lengths were implemented" is a non-starter, because whenever you decide that 7 should be allowed too, you *still* have to do a forklift upgrade on all the stuff that's got 4/16 baked into the silicon. Variable length was only going to work if it was in there from the start - otherwise you never get the first user of 8-byte or 20-byte to interoperate (in other words, the same exact problem we have right now getting legacy IPv4 to talk to anybody who isn't also doing IPv4).
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Current thread:
- Re: Waste will kill ipv6 too, (continued)
- Re: Waste will kill ipv6 too Mark Andrews (Dec 28)
- Re: Waste will kill ipv6 too Owen DeLong (Dec 28)
- Re: Waste will kill ipv6 too Lyndon Nerenberg (Dec 28)
- Re: Waste will kill ipv6 too Ricky Beam (Dec 28)
- Re: Waste will kill ipv6 too Mark Andrews (Dec 28)
- Re: Waste will kill ipv6 too Owen DeLong (Dec 28)
- Re: Waste will kill ipv6 too bzs (Dec 28)
- Re: Waste will kill ipv6 too Owen DeLong (Dec 28)
- Re: Waste will kill ipv6 too bzs (Dec 28)
- Re: Waste will kill ipv6 too Large Hadron Collider (Dec 28)
- Re: Waste will kill ipv6 too valdis . kletnieks (Dec 28)
- Re: Waste will kill ipv6 too sthaug (Dec 29)
- Re: Waste will kill ipv6 too Mikael Abrahamsson (Dec 29)
- Re: Waste will kill ipv6 too Nick Hilliard (Dec 29)
- Re: Waste will kill ipv6 too Owen DeLong (Dec 29)
- Re: Waste will kill ipv6 too Nick Hilliard (Dec 29)
- Re: Waste will kill ipv6 too William Herrin (Dec 29)
- Re: Companies using public IP space owned by others for internal routing james machado (Dec 17)
- Re: Companies using public IP space owned by others for internal routing Harry McGregor (Dec 17)