Joe, > Read this text. Tell me what part of it you do not understand regarding nodes > THAT DO NOT SUPPORT an option (if “skipping over” isn’t not supported, then > what is it?): > > The Option Type identifiers are internally encoded such that their > highest-order 2 bits specify the action that must be taken if the processing > IPv6 node does not recognize the Option Type: > 00 - skip over this option and continue processing the header. > ** 01 - discard the packet. > ** 10 - discard the packet and, regardless of whether or not the packet's > Destination Address was a multicast address, send an ICMP Parameter Problem, > Code 2, message to the packet's Source Address, pointing to the unrecognized > Option Type. > ** 11 - discard the packet and, only if the packet's Destination Address was > not a multicast address, send an ICMP Parameter Problem, Code 2, message to > the packet's Source Address, pointing to the unrecognized Option Type. > >>> I’m talking about a conflict in the text of 8200 - which has those fields >>> as required to support - and 7045, which says they can be silently ignored. >> >> 8200 says: >> If the router is explicitly configured to process the HBH header it MUST >> adhere to the option flag 2 high order bits. >> Otherwise it MUST forward the packet. >> >> There is no conflict. > > The conflict is in the issue of “not supported”. Skipping over headers means > they’re not supported, but it’s not possible to “NOT SUPPORT” them two > different ways - one silent, one that *requires* action.
I don’t know where you found the use of “support”. The text from RFC8200 is: The Option Type identifiers are internally encoded such that their highest-order 2 bits specify the action that must be taken if the processing IPv6 node does not recognize the Option Type: This only apply if you are actually processing the option in the first place. Which is a change from RFC2460. Cheers, Ole _______________________________________________ OPSEC mailing list [email protected] https://www.ietf.org/mailman/listinfo/opsec
