On Tuesday 19 February 2008, Marshall Eubanks wrote: > On Feb 19, 2008, at 3:39 PM, Brian E Carpenter wrote: > > On 2008-02-20 08:34, Marshall Eubanks wrote: > > ... > > > >> Not AFAICT in IPv6 : > >> > >> rfc2460 : > >> > >> o Unlike IPv4, when UDP packets are originated by an IPv6 > >> node, > >> the UDP checksum is not optional. That is, whenever > >> originating a UDP packet, an IPv6 node must compute a UDP > >> checksum over the packet and the pseudo-header, and, if > >> that > >> computation yields a result of zero, it must be changed > >> to hex > >> FFFF for placement in the UDP header. IPv6 receivers must > >> discard UDP packets containing a zero checksum, and > >> should log > >> the error. > > > > Of course, this decision was taken in parallel with the decision to > > drop > > the IP header checksum from IPv6. Nobody was quite ready to 100% trust > > the link layer. > > And the discussion about dropping this in IPv6 is in the context of > tunnel encapsulations where the > interior packet has a checksum. But "what is" the interior packet if the udp header is mangled and the ports were changed? AFAICT at least the header checksum is required when using IPv6. _______________________________________________ Ietf@xxxxxxxx http://www.ietf.org/mailman/listinfo/ietf