Hi Peter I think, considering we are using Ext Prefix LSA in 'Area-Flooding' scope, A should do PHP for 20.1.1.0/24 if C has advertised it. If A doesn’t pop for 20.1.1.0/24, and give the packet to B, it will drop it, since PHP is enabled by default for all nodes.
Regards Santanu -----Original Message----- From: Peter Psenak [mailto:ppse...@cisco.com] Sent: Thursday, April 02, 2015 1:08 PM To: Santanu Kar; ospf@ietf.org; sprev...@cisco.com; cfils...@cisco.com; han...@juniper.net; rob.sha...@bt.com; wim.henderi...@alcatel-lucent.com Subject: Re: PHP route determination in draft-ietf-ospf-segment-routing-extensions-03 Santanu, If B is not advertising a SID for 20.1.1.0/24, then A will not do PHP. regards, Peter On 4/2/15 08:39 , Santanu Kar wrote: > SANTANU> Iactually wanted to highlight the non-ABR cases here. > SANTANU> Consider > the3routers below,in same area. > > A -----10.1.1.0/24----- B ------20.1.1.0/24 -----C > > In thecontext of A, the route of 20.1.1.0/24 <http://20.1.1.0/24> is a > PHP route. Now the Prefix Segment for prefix 20.1.1.0/24 > <http://20.1.1.0/24> can be advertised by bothB, as well as by C > towards A. The case I am considering here is, C has advertised the > prefix segment of 20.1.1.0/24 <http://20.1.1.0/24> to Afirst.Stillwhen > A is calculating label for20.1.1.0/24 <http://20.1.1.0/24>,it should > take it as PHP. Howeverthe text in draft states "upstream neighbor of > the Prefix-SID originator MUST pop the Prefix-SID". Here A is not the > upstream neighbor of C. > -- . _______________________________________________ OSPF mailing list OSPF@ietf.org https://www.ietf.org/mailman/listinfo/ospf
