On 20/08/2013 16:02, Fernando Gont wrote: > Hi, Mike > > On 08/19/2013 09:58 PM, C. M. Heard wrote: >> My main question is why this draft is not better integrated with >> draft-wkumari-long-headers-01 and draft-bonica-6man-frag-deprecate, >> which have overlapping or at least related subject matter. > > Because what's in draft-ietf-6man-oversized-header-chain is what the wg > agreed upon over time.
And because taking baby steps when playing with such a basic aspect of the protocol seems wiser. I don't think the topics overlap; saying that the header chain must not be fragmented seems straightforward and non-controversial. The other drafts are more contentious. Brian > For instance, some earlier version of > draft-ietf-6man-oversized-header-chain enforced an upper limit t the > size of the extension header length (1280 bytes, at the time) but such > limit was removed from the document in responses to wg consensus. > > >> The thrust of draft-wkumari-long-headers-01 is the claim that >> operators have a requirement to filter at Layer 3 and Layer 4, at >> line rate, in the network, and that in order to be able to do that, >> the entire header chain needs to appear within a relatively short >> initial segment of the IPv6 datagram -- the draft suggests 128 >> bytes. This is MUCH shorter that the "within the first fragment" >> constraint specified by draft-ietf-6man-oversized-header-chain. > > And it was agred by this wg that this limit would be an operational BCP, > but not a protocol update. That's thy these items are kept in different > documents. > > > > >> There is also a strong hint (though not an explicit statement) in >> draft-wkumari-long-headers-01 that entities that do in-network >> line-rate filtering need to see layer 3 and 4 information in ALL >> datagrams, which is at the heart of the subject matter of >> draft-bonica-6man-frag-deprecate. > > The wg discussed this, and I seem to recall that the outcome was that we > were not ready to ban the use of fragmentation, but rather that we > should move away from it. > > Cheers, -------------------------------------------------------------------- IETF IPv6 working group mailing list [email protected] Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
