Hi, Jouni,
2012-12-12 10:04, Jouni Korhonen <[email protected]> : > > Hi, > > > On Dec 8, 2012, at 2:14 AM, Suresh Krishnan <[email protected]> > wrote: > >> Hi all, >> >> The 4rd draft (http://tools.ietf.org/html/draft-ietf-softwire-4rd-04) >> describes a solution for providing IPv4 connectivity over IPv6. The >> draft describes the method for mapping 4rd IPv4 addresses to 4rd IPv6 >> Addresses. It uses a 4rd specific mark called the V octet in the first 8 > > V-octet was AFAIR first time discussed within the Softwire MAP design team > and I had/expressed my concerns already that time. My argumentation was that > we cannot just redefine the u & g bit use without actually having it verified > against and reflected in RFC4291. Glad to see it happening now ;) > > IMHO the current language in RFC4291 does not give enough freedom to use > u=g=1, since such combination is not specifically left unused/reserved > (although u=g=1 makes no sense for the current IPv6). > IEEE allows MAC > addresses that have I/G set to 1 and U/L set to 0, which makes me rather > uncomfortable with IETF using u=g=1 for their own purposes. IEEE indeed permits group addresses for multiple interfaces that share a common address but, as we are in the context of IPv6 UNICAST addresses, interface all our IEEE-address derived IIDs have g=0. IETF can take advantage of this fact without risk to interfere with IEEE, For more details, please see my last answer to Bob. Regards, RD > - Jouni > > >> bits of the Interface Identifier. There were some concerns raised in >> softwire about whether such addresses are actually compatible with the >> IPv6 addressing architecture. Whether this is actually compatible with >> the IPv6 addressing architecture is outside the scope of the softwire >> wg. Hence we would like to hear the 6man wg's perspective on this. I >> would like to request the wg to please go over the NOTE in Section 4.5 >> page 18, which explains the issue, and over IANA Considerations Section >> 6, and chime in on whether this is acceptable from a 6man perspective. >> >> Thanks >> Suresh >> -------------------------------------------------------------------- >> IETF IPv6 working group mailing list >> [email protected] >> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 >> -------------------------------------------------------------------- > > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > [email protected] > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
