nanog mailing list archives
Re: Using /126 for IPv6 router links
From: Valdis.Kletnieks () vt edu
Date: Sun, 24 Jan 2010 18:26:14 -0500
On Sun, 24 Jan 2010 17:01:21 EST, Steven Bellovin said:
Actually, Scott Bradner and I share most of the credit (or blame) for the change from 64 bits to 128. During the days of the IPng directorate, quite a number of different alternatives were considered. At one point, there was a compromise proposal known as the "Big 10" design, because it was propounded at the Big Ten Conference Center near O'Hare. One feature of it was addresses of length 64, 128, 192, or 256 bits, determined by the high-order two bits. That deal fell apart for reasons I no longer remember;
I don't remember the details of Big 10, but I do remember the general objection to variable-length addresses (cf. some of the OSI-influenced schemes) was the perceived difficulty of building an ASIC to do hardware handling of the address fields at line rate. Or was Big 10 itself the compromise to avoid dealing with variable-length NSAP-style addresses ("What do you mean, the address can be between 7 and 23 bytes long, depending on bits in bytes 3, 12, and 17?" :)
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- Re: Using /126 for IPv6 router links, (continued)
- Re: Using /126 for IPv6 router links Larry Sheldon (Jan 23)
- Re: Using /126 for IPv6 router links Brandon Galbraith (Jan 23)
- Re: Using /126 for IPv6 router links Mark Smith (Jan 23)
- Re: Using /126 for IPv6 router links Owen DeLong (Jan 23)
- Re: Using /126 for IPv6 router links Larry Sheldon (Jan 23)
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- Re: Using /126 for IPv6 router links Larry Sheldon (Jan 23)
- Re: Using /126 for IPv6 router links Valdis . Kletnieks (Jan 24)
- Re: Using /126 for IPv6 router links Larry Sheldon (Jan 24)
- Re: Using /126 for IPv6 router links Owen DeLong (Jan 24)
- Re: Using /126 for IPv6 router links Mark Smith (Jan 24)
- Re: Using /126 for IPv6 router links Steven Bellovin (Jan 24)
- Re: Using /126 for IPv6 router links Valdis . Kletnieks (Jan 24)
- Re: Using /126 for IPv6 router links Steven Bellovin (Jan 24)
- Re: Using /126 for IPv6 router links Mark Smith (Jan 24)
- Re: Using /126 for IPv6 router links Rubens Kuhl (Jan 24)
- Re: Using /126 for IPv6 router links Andy Davidson (Jan 25)
- Re: Using /126 for IPv6 router links Richard A Steenbergen (Jan 25)
- RE: Using /126 for IPv6 router links TJ (Jan 25)
- Re: Using /126 for IPv6 router links Richard A Steenbergen (Jan 25)
- RE: Using /126 for IPv6 router links TJ (Jan 25)
- Re: Using /126 for IPv6 router links Tim Durack (Jan 25)
- Re: Using /126 for IPv6 router links Ryan Harden (Jan 25)