Richard Barnes wrote: > Document: draft-ietf-6man-udpzero-06 It's interesting that the draft denies the following statements in RFC2765: Fragmented IPv4 UDP packets that do not contain a UDP checksum (i.e. the UDP checksum field is zero) are not of significant use over wide-areas in the Internet and will not be translated by the translator. While the draft considers only tunnels and states: IPv6 middlebox deployment is not yet as prolific as it is in IPv4. Thus, relatively few current middleboxes may actually block IPv6 UDP with a zero checksum. interactions between the draft and existing implementations of RFC2765 will be quite exciting. The following statement of the draft: The computed checksum value may be cached (before adding the Length field) for each flow /destination and subsequently combined with the Length of each packet to minimise per-packet processing. is bogus, because searching cache means a lot more effort than recomputing checksum. Masataka Ohta