On Tue, Jun 23, 2015 at 9:24 PM, Liyizhou <liyiz...@huawei.com> wrote: > Probably it requires at least the edge nodes to be all upgraded to prevent > the leaking to the user. Either the deployment should guarantee that or some > mechanism like capability exchange would be used. > > IMHO prohibiting any usage of reserved bits is frustrating and goes against > the original intention to even having "reserved bits".
Indeed it is frustrating. This is precisely why in GUE we require a receiver do drop any packet with unknown flag bits set-- this avoids the forward compatibility problem from the get-go. In any case, this problem should at least be mentioned in the draft and what steps need to be taken to avoid issues in practice. Tom > > Thank, > Yizhou > > -----Original Message----- > From: nvo3 [mailto:nvo3-boun...@ietf.org] On Behalf Of Tom Herbert > Sent: Tuesday, June 23, 2015 10:21 PM > To: Dapeng Liu > Cc: nvo3@ietf.org > Subject: Re: [nvo3] New draft: Path Detection in VXLAN Overlay Network > > On Sat, Jun 20, 2015 at 1:04 PM, Dapeng Liu <maxpass...@gmail.com> wrote: >> Hello all, >> >> We have submitted a draft for path detection in VXLAN overlay network. >> http://datatracker.ietf.org/doc/draft-pang-nvo3-vxlan-path-detection/ >> >> The draft proposes a method for path detection in VXLAN network and it >> defines the path detection packet format by using one reserve bit in >> the VXLAN header. >> >> Comments & suggestions are welcomed. >> > > "PD (1 bit) - Indicates it is a PD packet and needs to be handled as > specified in this document." This does not seem not forward compatible since > per RFC7348 reserved bits are ignored on receipt. Since the VXLAN draft > purposely is putting valid headers in the VXLAN payload, I don't see anything > that would prevent misinterpretation if such a packet is sent to a legacy > device. Other attempts to extend VXLAN have hit this same problem, and it is > probably also an issue in for nvgre. > > Thanks, > Tom > > > >> >> -- >> Dapeng Liu >> >> >> _______________________________________________ >> nvo3 mailing list >> nvo3@ietf.org >> https://www.ietf.org/mailman/listinfo/nvo3 >> > > _______________________________________________ > nvo3 mailing list > nvo3@ietf.org > https://www.ietf.org/mailman/listinfo/nvo3 _______________________________________________ nvo3 mailing list nvo3@ietf.org https://www.ietf.org/mailman/listinfo/nvo3
