Brian E Carpenter <[email protected]> wrote: > > I'm not hearing much in response to the open issue: > > Should we delete most of the text concerning stateful methods > of handling the flow label?
I don't really have a horse in that race, but at first blush I'd say the I-D goes into too much detail about stateful handling. IMHO, most handling (assuming it happens at all) will be stateless, and will greatly resemble "damage" (as in what we route-around). > In fact I'm not hearing much at all. Should I ask the WG Chairs > to conclude that everybody is OK with these drafts? That would > save us some time in Prague... I won't be in Prague... :^( But while this I-D is a step in the right direction, where I think we ought to get should allow much more leeway in setting -- even changing -- Flow Labels _by_prior_arrangement_. The basic assumption that Flow Labels will be set by the sender and passed unchanged is certainly correct in the absence of arrangements that specify particular processing. I am a bit nervous about _always_ allowing a zero Flow Label to be changed without sender consent... But clearly, there _can_ be no protection against such changes -- or any changes, for that matter. My intuition is that any time the Traffic Class is changed during forwarding, rules about Flow Label particular to that Traffic Class should apply. Further, there probably need to be _various_ largely out-of-band mechanisms to validate a contractual basis for special handling of packets based upon Flow Labels. There could be one or more in-band mechanisms if we had what I'll call a "Middlebox Options" extension header (between Hop-by-Hop and Destination Options) to store validation information. Fundamentally, I don't believe the completely-insecure Flow Label can serve by itself as sufficient justification for special handling; and I don't believe that the sender alone can justify special handling by _all_ the different service-providers along the forwarding path. I think more infrastructure will need to evolve. Legislating what we can't specify any means to enforce isn't wise... ==== Disclaimer: I in some sense "represent" the ConEx WG, where several folks want to reserve one bit from the Flow Label for ConEx use. I am _not_ the right person to put the case for that, because frankly I don't agree with the idea. Nonetheless, it seems reasonable to me to allow things like that on an Experimental basis if clearly labeled by setting an Experimental Traffic Class. -- John Leslie <[email protected]> -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
