Please see previous comments in this thread, such as this one: http://openvswitch.org/pipermail/dev/2016-July/074980.html
On Wed, Jul 13, 2016 at 10:06 AM, Brady Allen Johnson <brady.allen.john...@ericsson.com> wrote: > Is the current implementation really dependent on Simon's patch? > > I understood that the current implementation is for ethernet+NSH and > VXLAN+ethernet+NSH which doesnt require Simon's patch. Simon's patch would > be needed for VXLAN-GPE+NSH, which is not in this implementation. Maybe the > authors can verify this. > > Regards, > > Brady > > > > On 13/07/16 18:59, Jesse Gross wrote: >> >> On Wed, Jul 13, 2016 at 7:55 AM, Jiri Benc <jb...@redhat.com> wrote: >>> >>> On Wed, 13 Jul 2016 07:35:59 -0700, Jesse Gross wrote: >>>> >>>> I think history tells us how this will end - similar to IPv4 options, >>>> implementations that don't implement TLVs will become deployed and >>>> then when there is a use for them it's no longer possible. Since I >>>> don't want OVS to have a half implementation or contribute to this >>>> issue, I'd like to see the whole protocol implemented before I apply >>>> anything. >>> >>> I see a big difference between this and IPv4. While in IPv4, the >>> options are extension to existing headers, here we're talking about a >>> completely different payload. It's more comparable to http vs. ftp (of >>> course, it's a poor comparison, but I hope it illustrates at least a >>> bit what I mean). >>> >>> If NSH takes off (and it's a big "if" in my opinion), it's also well >>> possible we'll see more metadata types. The spec is pretty much open to >>> this. Obviously, the authors are aware of that and type 2 is optional. >>> As I guess will be type 3 and type 4 and whatever. >>> >>> It's pretty much inevitable that applications and deployments built >>> around MD type 1 won't support MD type 2. And vice versa. This is >>> regardless whether ovs supports MD type 2 or not. They're just a >>> different protocol. >>> >>> In my opinion, starting with MD type 1 is a good way to reduce the >>> initial scope. I see no problem with adding MD type 2 later. >> >> I understand what you are saying but I'm not sure that I agree that >> the two metadata types should be viewed as essentially independent >> protocols. I guess it's probably also pretty unlikely that additional >> metadata types will be created in the future. >> >> If you look at discussions in the IETF and other places, it seems like >> a frequent response to questions about MD type 1's design is that any >> limitations can be handled with type 2. So to me this looks like the >> two pieces are interrelated and the situation is quite similar to >> IPv4. >> >> In any case, I don't think this is a fundamental issue, just a matter >> of timing. Since the premise of the original question was that MD type >> 2 shouldn't be too much additional work and the series is currently >> dependent on Simon's patches, it seems like now might be a good time >> for the authors to look into implementing this. > > _______________________________________________ dev mailing list dev@openvswitch.org http://openvswitch.org/mailman/listinfo/dev
