Re: [Tsv-art] HbH flags [Tsvart last call review of draft-ietf-opsec-ipv6-eh-filtering-06]

[Ole Troan <[e-mail]>]

Joe,

I think you misunderstand.

> 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.

If you think a different behaviour is required, then propose that. But preferably in 6man and on a different thread.

This was discussed at length. The consequence of relaxing the processing rules, is that an end-host can no longer use those bits to guarantee that every router on the path implements the option. That was the compromise we accepted. There is clearly a need for something like HBH, where it’s a cheap to process for the router signal that this packet requires further attention. The alternative is much worse, that the router must parse deep into the packet and where the trigger to process is a magic cookie in transport somewhere (and yes this has been proposed). 

Ole