Senthil,
2013-01-2815:24, Senthil Sivakumar (ssenthil) <[email protected]> : > I believe the prefix length > 64 should be allowed. > It is upto the > operator to choose the prefix length of their choice. Agreed. No one suggest to say the contrary. Yet, operators have the constraint of RFC 4291 that "For all unicast addresses, except those that start with the binary value 000, Interface IDs are required to be 64 bits long and to be constructed in Modified EUI-64 format". The draft says that: (a) The PSID is: +--+---+---+---+---+---+---+---+---+ |PL| 8 16 24 32 40 48 56 | +--+---+---+---+---+---+---+---+---+ |64| u | IPv4 address | PSID | 0 | +--+---+---+---+---+---+---+---+---+ (b) "If the End-user IPv6 prefix length is larger than 64, the most significant parts of the interface identifier is overwritten by the prefix." This is particularly unclear: - What happens to the u octet? - And to the IPv4 address if the prefix is longer than /68? - ... Of course, if a use case is provided where MAP-E would be actually used with an IID shorter than 64 bits, it should be discussed. But: - There is no such use case so far. - Looking for one doesn't seem useful. Regards, RD > > On 1/28/13 8:59 AM, "Ole Troan" <[email protected]> wrote: > >>>>> >>>>> The examples in my previous note sort of provided backing for my view >>>>> that the MAP endpoint IPv6 prefix can be limited to a maximum of a >>>>> /64, thus making the IID fully conformant both to RFC 4291 and to RFC >>>>> 6052. >>>>> >>> ... >>> >>>>> >>>>> I think limiting the prefix length to 64 bits is reasonable. Comments? >>>> >>>> I don't think that's reasonable. >>>> and I don't see what it buys us, given that supporting prefix lengths >>>> longer than 64 is simple. >>>> IPv6 isn't classfull, there isn't anything magic with the 64 boundary. >>>> ;-) >>>> >>>> cheers, >>>> Ole >>>> >>> >>> OK, then I agree with Rémi. Drop mention of prefixes greater than 64 >>> bits long and leave it to the reader to judge whether RFC 4291 imposes a >>> limit. >> >> you want this removed: >> <t>If the End-user IPv6 prefix length is larger than 64, the most >> significant parts of the interface identifier is overwritten by the >> prefix.</t> >> >> I disagree. this is the only text in there suggesting to an implementor >> that prefix lengths can be any value between 0-128. >> >> Tom, Remi and I have stated our opinions. does anyone else have a view on >> the matter? >> >> cheers, >> Ole >> _______________________________________________ >> Softwires mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/softwires > > _______________________________________________ > Softwires mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/softwires _______________________________________________ Softwires mailing list [email protected] https://www.ietf.org/mailman/listinfo/softwires
