Hi Santosh, Even for single-hop we had discussions about implementations which support the option of having multiple BFD single-hop sessions on 1 interface between 2 endpoints. That was an argument for having the BFD config in routing applications. This is what was discussed today in the WG. And I think Greg's point is that we don't have to support this in the base model, but implementations are have vendor specific model which supports this behaviour.
Regards, Reshad. From: Rtg-bfd <[email protected]<mailto:[email protected]>> on behalf of Santosh P K <[email protected]<mailto:[email protected]>> Date: Tuesday, November 3, 2015 at 1:25 AM To: Gregory Mirsky <[email protected]<mailto:[email protected]>>, "[email protected]<mailto:[email protected]>" <[email protected]<mailto:[email protected]>> Subject: RE: Multiple BFD sessions between the same pair of end-points This is form RFC 5881 section 3. In this application, there will be only a single BFD session between two systems over a given interface (logical or physical) for a particular protocol. The BFD session must be bound to this interface. Which says for singlehop you will have only single BFD session for an interface. The case where we are struggling in Yang is for multihop BFD session. Thanks Santosh P K From: Rtg-bfd [mailto:[email protected]] On Behalf Of Gregory Mirsky Sent: Tuesday, November 03, 2015 7:57 AM To: [email protected]<mailto:[email protected]> Subject: Multiple BFD sessions between the same pair of end-points Dear All, I think that this paragraph from Section 2 of RFC 5881 prohibits multiple single-hop BFD sessions between the same pair of end points: Each BFD session between a pair of systems MUST traverse a separate network-layer path in both directions. This is necessary for demultiplexing to work properly, and also because (by definition) multiple sessions would otherwise be protecting the same path. Regards, Greg
