nanog mailing list archives
Re: Definitive Guide to IPv6 adoption
From: Mark Andrews <marka () isc org>
Date: Tue, 19 Oct 2010 12:32:05 +1100
In message <35804BC3-9EFE-4CE4-B13A-F2E15C420EFA () americafree tv>, Marshall Euba nks writes:
It makes a bigger difference if everyone starts using 6RD - to give out = a /48 effectively=20 requires a /16, and the number of /16s is by no means approximately = infinite.=20 Regards Marshall
Only if you deploy 6rd in a naive manner. Encoding all of IPv4 into the IPv6 prefix you hand your customers in naive. The best way is to just have a table that matches 6rd prefixes to IPv4 blocks you have assigned. This table only changes when you add or remove a IPv4 assignments from RIRs. You don't change existing entries in the table. The entries are static for the life of the IPv4 allocation. <6rdPrefix1><6rdPefixLen1><IPv4Prefix1><IPv4PrefixLen1> <6rdPrefix2><6rdPefixLen2><IPv4Prefix2><IPv4PrefixLen2> <6rdPrefix3><6rdPefixLen3><IPv4Prefix3><IPv4PrefixLen3> When you configure a IPv4 DHCP pool and associated router interface you find the covering IPv4 prefix and plug in the values from the table. The next best way is to have a similar table but per covering IPv4/8 you have allocated. This is very wasteful but not as having a IPv4PrefixLen of 0. <6rdPrefix1><6rdPefixLen><192.0.0.0><8> <6rdPrefix2><6rdPefixLen><202.0.0.0><8> For the global naive case the table degenerates to a single row. <6rdPrefix><6rdPefixLen><0.0.0.0><0> As a exercise the first table was ~20 entries for Comcast Cable and the second table about ~10 entries if I did the lookup correctly so we are not talking about a lot of prefixes and they don't change very often. Mark -- Mark Andrews, ISC 1 Seymour St., Dundas Valley, NSW 2117, Australia PHONE: +61 2 9871 4742 INTERNET: marka () isc org
Current thread:
- Re: Definitive Guide to IPv6 adoption, (continued)
- Re: Definitive Guide to IPv6 adoption Jack Bates (Oct 18)
- Re: Definitive Guide to IPv6 adoption Franck Martin (Oct 18)
- Re: Definitive Guide to IPv6 adoption Jack Bates (Oct 18)
- RE: Definitive Guide to IPv6 adoption Schiller, Heather A (HeatherSkanks) (Oct 19)
- Re: Definitive Guide to IPv6 adoption Jack Bates (Oct 19)
- Re: Definitive Guide to IPv6 adoption Owen DeLong (Oct 19)
- Re: Definitive Guide to IPv6 adoption Lee (Oct 19)
- Re: Definitive Guide to IPv6 adoption Robert E. Seastrom (Oct 18)
- Re: Definitive Guide to IPv6 adoption Marshall Eubanks (Oct 18)
- Re: Definitive Guide to IPv6 adoption Robert E. Seastrom (Oct 18)
- Re: Definitive Guide to IPv6 adoption Mark Andrews (Oct 18)
- Re: Definitive Guide to IPv6 adoption Owen DeLong (Oct 19)
- Re: Definitive Guide to IPv6 adoption David Conrad (Oct 18)
- Re: Definitive Guide to IPv6 adoption Owen DeLong (Oct 19)
- Re: Definitive Guide to IPv6 adoption Doug Barton (Oct 18)
- Re: Definitive Guide to IPv6 adoption Owen DeLong (Oct 19)
- Re: Definitive Guide to IPv6 adoption Dan White (Oct 19)
- Re: Definitive Guide to IPv6 adoption Doug Barton (Oct 19)
- RE: Definitive Guide to IPv6 adoption George Bonser (Oct 18)
- Re: Definitive Guide to IPv6 adoption Eugen Leitl (Oct 19)
- RE: Definitive Guide to IPv6 adoption George Bonser (Oct 19)