+1 Hi Oliver,
Technically Adj-SID refers to an IGP adjacency between two nodes as per RFC8402 semantics. I don't think a passive (stub) link falls under that category. It would be better to define a passive link separately (somewhat on lines of what was done for inter-AS TE) so that it does not get mixed up with the classical IGP links. I would think a new draft would be apt for such an extension. Thanks, Ketan -----Original Message----- From: Lsr <[email protected]> On Behalf Of Acee Lindem (acee) Sent: 10 May 2019 17:39 To: Christian Franke <[email protected]>; [email protected]; SPRING <[email protected]>; LSR <[email protected]> Subject: Re: [Lsr] Adjacency SID and Passive Interface Hi Chris, Olivier, On 5/10/19, 4:41 AM, "Lsr on behalf of Christian Franke" <[email protected] on behalf of [email protected]> wrote: On 5/10/19 9:58 AM, [email protected] wrote: > In the current state of Segment Routing drafts, do you think it is possible to advertise > Adjacency SID on such passive or inter-domain interfaces or do we need to specify this behaviour > in a new draft ? > > For me I don't see anything in the drafts that prohibits this kind of advertisement, but perhaps I'm wrong. My understanding is that the SID is specific to an adjacency and advertised in IS-IS in either TLV 22, 222, 23, 223. As adjacencies will not be formed on a passive interface, an adjacency SID should not be advertised for the passive interface. I agree with Chris. We shouldn't reuse the existing Adj-SID when there will never be an adjacency and the current semantics require this. If we need advertisement of SIDs for passive interfaces, it would definitely be a new draft that clearly articulates the use case and designates a new type of SID that has different semantics. Also note that while passive interfaces are very useful in order to include a stub network in the topologies, they are not part of the OSPF specifications. I haven't done an exhaustive search on IS-IS. Thanks, Acee I might also be wrong here, though. All Best, Chris _______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr _______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr _______________________________________________ Lsr mailing list [email protected] https://www.ietf.org/mailman/listinfo/lsr
