Hello Larry, Weiguo and Greg, there seem multiple ideas or requirements for OAM. I mentioned in another thread (started by Erik) that we may want "punt, don't forward" as well as "punt & forward". The forwarding would stay in the fast data plane.
And instead of flags I propose to use a protocol/next-header field (which seems to exist in several of the proposed data plane encapsulations) and let the hardware react on this field, so introducing different OAM behaviour is "simple" on the encoding side. The OAM would then carry information like counters in a TLV sitting between the initial header and the payload. > If it is more than a flag (and I assume it would be), and is not mandatory > for all implementations, then it seems to fall into the category of > optional extensions. Agree, unless the control plane ensures that features like OAM are only used when all nodes support it. This would shift some complexity from the (fast) data plane into the control plane. Regards, Marc On Tue, 11 Nov 2014 20:33:26 +0000, Larry Kreeger (kreeger) wrote: > Hi Weiguo, > > What do you envision this marking looking like? e.g. is it just a single > flag bit, or large field with a counter or sequence number, or some kind of > flow ID? If not a single flag, how large do you see the field being? > > If it is more than a flag (and I assume it would be), and is not mandatory > for all implementations, then it seems to fall into the category of > optional extensions. > > Thanks, Larry > > From: Haoweiguo <[email protected]> > Date: Tuesday, November 11, 2014 10:18 AM > To: Greg Mirsky <[email protected]> > Cc: "[email protected]" <[email protected]> > Subject: [nvo3] 答复: Comments on NVO3 data plane requirements for OAM > > Hi Greg, > I fully agree with you. > The real time OAM is passive performance measurement methods. I would like > NVO3 data encapsulation has a field for marking and not affect forwarding > of packets, the marking field is only used for performance measurement. The > NVO3 packet with this marking flag don't need to be sent to control plane, > it is different from OAM(ping/Trace) packet processing. > Thanks > weiguo > > 发件人: Greg Mirsky [[email protected]] > 发送时间: 2014年11月12日 4:07 > 收件人: Haoweiguo > 抄送: [email protected] > 主题: Re: [nvo3] Comments on NVO3 data plane requirements for OAM > > > Hi Weiguo, > marking groups of packets that belong to the particular flow to facilitate > measurement of some performance metric, whether loss or delay/delay > variation, may be viewed as one of passive performance measurement methods. > But such marking should not alter, at least not significantly alter, > treatment of data flow in the network. Because of that, I believe, OAM flag > should not be used for marking as that will force punting marked packets > from fast forwarding path to the control plane. But it might be good to > have a field in NVO3 header that may be used for marking and not affect > forwarding of packets if altered. > > Regards, > Greg > > On Tue, Nov 11, 2014 at 12:34 AM, Haoweiguo <[email protected]> wrote: >> Hi All, >> I maybe not clearly said in today’s NVO3 meeting, pls allow me to >> reiterate the OAM data plane requirements on the mail list. >> Currently NVO3 data plane encapsulation only includes one OAM flag, it is >> used for Ping/Trace similar applications. This kind of OAM application is >> initiated by operators for network connectivity verification, normally >> when network failure occurs. There is another OAM requirements of real >> time OAM or synthesizing OAM. It can be used for packet loss detection in >> real time. When ingress NVE receives traffic from local TS, it gets packet >> statistics, and mark(coloring) the OAM flag relying on local policy when >> it performs NVO3 encapsulation. When egress NVEs receives the traffic, it >> decapsulates NVO3 encapsulation, and gets packet statistics with the real >> time OAM flag marking. By comparing the packet number of ingress NVE and >> the sum of all egress NVEs, packet loss can be deduced. This method can be >> applicable for both unicast and multicast traffic. Local policy on ingress >> NVE is configured by operators or automatically acquired from centralized >> orchestration. >> Thanks >> weiguo >> >> _______________________________________________ >> nvo3 mailing list >> [email protected] >> https://www.ietf.org/mailman/listinfo/nvo3 >> > > > > _______________________________________________ > nvo3 mailing list > [email protected] > https://www.ietf.org/mailman/listinfo/nvo3 _______________________________________________ nvo3 mailing list [email protected] https://www.ietf.org/mailman/listinfo/nvo3
