> -----Original Message----- > From: Rémi Després [mailto:[email protected]] > Sent: Monday, July 25, 2011 8:38 AM > To: Dan Wing > Cc: 'james woodyatt'; 'RJ Atkinson'; [email protected] > Subject: Re: PMTUD and MTU < 1280 > > > Le 23 juil. 2011 à 04:34, Dan Wing a écrit : > > >> -----Original Message----- > >> From: [email protected] [mailto:[email protected]] On Behalf > Of > >> james woodyatt > >> Sent: Wednesday, July 20, 2011 2:44 PM > >> To: RJ Atkinson > >> Cc: [email protected] > >> Subject: Re: PMTUD and MTU < 1280 > >> > >> On Jul 20, 2011, at 14:35 , RJ Atkinson wrote: > >> > >>> One hopes IPv6 implementers will be tolerant of IPv6 MTUs below > 1280 > >> bytes, because they do exist in the deployed world and aren't going > >> away anytime soon. > >> > >> Those hopes are not well placed. > >> > >> I am aware of at least one packet filter implementation-- which > might > >> be refined in the future, one hopes, to conform fully with RFC 6092- > - > >> that treats this behavior as a resource exhaustion attack and drops > >> flows accordingly. > > > > Its behavior violates the last paragraph of Section 5 of RFC2460. > > Violation _only in case_ of "an IPv6 packet that is sent to an IPv4 > destination".
But how does one determine an IPv6 packet is, or isn't, going to an IPv4 destination? I don't think it's possible to determine if there is an IPv6/IPv4 translator on the path. -d > If the destination is IPv6, a PMTU below 1280 remains therefore a > network failure. > This authorizes a simple IPv6 host to refuse packets beyond 1280 octets > and to have no support of packet-reassembly. > > Right? > > Regards, > RD > > > > > > > -d > > > >> > >> -- > >> james woodyatt <[email protected]> > >> member of technical staff, core os networking > >> > >> > >> > >> -------------------------------------------------------------------- > >> 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 --------------------------------------------------------------------
