Tom, it might also be helpful to think of the new HBH option as a "Don't Fragment (DF)" flag for IPv6. If the option is absent, then it is the equivalent of DF=1 and the network is not permitted to fragment. If the option is present, then it is DF=0 and the network can fragment if necessary.
Fred > -----Original Message----- > From: Int-area <int-area-boun...@ietf.org> On Behalf Of Templin (US), Fred L > Sent: Friday, September 01, 2023 8:17 AM > To: Tom Herbert <tom=40herbertland....@dmarc.ietf.org>; Templin (US), Fred L > <Fred.L.Templin=40boeing....@dmarc.ietf.org> > Cc: int-area@ietf.org; i...@ietf.org > Subject: Re: [Int-area] [IPv6] FW: I-D Action: > draft-templin-intarea-ipid-ext-04.txt > > Tom, a correction: > > > This started out as a destination option *after* the Fragment header but > > *before* > > the Routing header according to the order stipulated in RFC8200. > > I meant a destination option *before* both the routing and fragment headers > per > Section 4.1 of RFC8200. But regardless, I now still do want to use hop-by-hop. > > Fred > > > -----Original Message----- > > From: Templin (US), Fred L > > Sent: Friday, September 01, 2023 8:11 AM > > To: 'Tom Herbert' <tom=40herbertland....@dmarc.ietf.org>; Templin (US), > > Fred L <Fred.L.Templin=40boeing....@dmarc.ietf.org> > > Cc: int-area@ietf.org; i...@ietf.org > > Subject: Re: [IPv6] [Int-area] FW: I-D Action: > > draft-templin-intarea-ipid-ext-04.txt > > > > Tom, see below: > > > > > Hi Fred, > > > > > > I don't see how the Hop-by-Hop Option can work. In IPv6, fragmentation > > > is always end to end so a Hop-by-Hop Option really isn't appropriate. > > > It should be a Destination Option, but then we'd have to have DestOps > > > before the Frag header but after any Routing Header which would > > > diverge from the recommended EH ordering in section 4.1 of RFC8200. > > > Also, it seems the high order bits of the option type can't be 00 > > > (presumably the option must be processed in order to correctly perform > > > reassembly), if this is done in a Hop-by-Hop Options then an > > > intermediate node may drop the packet even though it doesn't care > > > about fragmentation. > > > > This started out as a destination option *after* the Fragment header but > > *before* > > the Routing header according to the order stipulated in RFC8200. But, then I > > realized that I wanted to enable network fragmentation for IPv6 and for that > > I needed a hop-by-hop option to tell intermediate IPv6 hops that recognize > > the option that fragmentation is permitted. This document updates RFC8200. > > > > Fred > > > > > Tom > > > > > > > > > > > The IETF datatracker status page for this Internet-Draft is: > > > > https://datatracker.ietf.org/doc/draft-templin-intarea-ipid-ext/ > > > > > > > > There is also an HTMLized version available at: > > > > https://datatracker.ietf.org/doc/html/draft-templin-intarea-ipid-ext-04 > > > > > > > > A diff from the previous version is available at: > > > > https://author-tools.ietf.org/iddiff?url2=draft-templin-intarea-ipid-ext-04 > > > > > > > > Internet-Drafts are also available by rsync at: > > > > rsync.ietf.org::internet-drafts > > > > > > > > > > > > _______________________________________________ > > > > I-D-Announce mailing list > > > > i-d-annou...@ietf.org > > > > https://www.ietf.org/mailman/listinfo/i-d-announce > > > > > > > > _______________________________________________ > > > > Int-area mailing list > > > > Int-area@ietf.org > > > > https://www.ietf.org/mailman/listinfo/int-area > > > > > > -------------------------------------------------------------------- > > > IETF IPv6 working group mailing list > > > i...@ietf.org > > > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > > > -------------------------------------------------------------------- > _______________________________________________ > Int-area mailing list > Int-area@ietf.org > https://www.ietf.org/mailman/listinfo/int-area _______________________________________________ Int-area mailing list Int-area@ietf.org https://www.ietf.org/mailman/listinfo/int-area
