Some corrections/additions in my response earlier… On 8/19/15, 3:47 PM, "spring on behalf of Pushpasis Sarkar" <[email protected]<mailto:[email protected]> on behalf of [email protected]<mailto:[email protected]>> wrote:
Hi Peter, On 8/19/15, 3:27 PM, "Peter Psenak" <[email protected]<mailto:[email protected]>> wrote: Hi Pushpasis, On 8/19/15 10:43 , Pushpasis Sarkar wrote: Hi Peter, On 8/19/15, 1:22 PM, "Peter Psenak" <[email protected]<mailto:[email protected]>> wrote: Stephane, there are two things involved here - configuration and advertisement. If you look at the SR drafts for both IGPs, both MTID and algorithm is advertised with Prefix SID, not with SRGB. [Pushpasis] Again IMO, SRGBs published per topology and hence ISIS/OSPF SR extensions should be modified to add an optional MTID field as well. please bear in mind that there are implementation out there in the field with the existing encoding. [Pushpasis] That’s why I said that MTID in SR-Capability should be optional. The SRGB for the default topology can be encoded without a MTID (no impact to current implementation). The SRGB for other topologies can be encoded with a MTID field. Might as well be a separate MT-SRCapabality subTLV. If you move the MTID/algorithm fileds from Prefix SID to SRGB, what is the MTID/algorithm fields in prefix SID used for? [Pushpasis] The MTID in prefix TLV is for having the index associated with the prefix. If one uses the same index with differenet MTIDs(different topologies) the label allocated for the same prefix for the two different topologies shall be different same. If the forwarding path for the prefix for one topology needs to be different than the other, having the same label for the same prefix for the two different topology is not an option. Hence we need a different SRGB for each topology. That’s why we need a MTID in the SR-Capability. Having the MTID/algorithm fileds in both Perfix SID and SRGB would be redundant and confusing. That does not mean you have to manually configure prefix SID for each MTID or algorithm - there are ways how this can be achieved in an automated way while advertising a single topology/algorithm agnostic SRGB. [Pushpasis] I am assuming by 'automated way’ you still mean separate indexes per topology for the same prefix. Right? advertisement wise yes, config wise no. [Pushpasis] I did not understand how advertisement can be different from configuration. In my understanding advertisements are derived from configurations. Thanks -Pushpasis thanks, Peter Thanks -Pushpasis thanks, Peter On 8/19/15 09:36 , [email protected]<mailto:[email protected]> wrote: Hi, We come back to the same discussion for MT as for per algorithm SRGB. Do we need for operational reason the same index value to be configured for different algorithm or topologies ? IMO, it is useful operationally otherwise adding a topology or algorithm would be painful ... Adding a new index value is like assigning a new prefix but here we want to use the same prefix. Stephane -----Original Message----- From: spring [mailto:[email protected]] On Behalf Of Pushpasis Sarkar Sent: Wednesday, August 19, 2015 09:06 To: Peter Psenak; Eric Rosen; SPRING WG Subject: Re: [spring] SRGBs, indexes, and topologies within a domain Hi Peter, On 8/19/15, 12:01 PM, "Peter Psenak" <[email protected]<mailto:[email protected]>> wrote: SR protocol extensions clearly do - they advertise MTID with the prefix SID, not with SRGB. [Pushpasis] Do you mean that a separate index per topology is mandatory? That won¹t be a good idea in my opinion. Operators SHOULD have flexibility to choose a separate or same index for the same prefix under different topology. Not sure how other members (especially the operators) think about the same. Request SR authors to re-consider this. Thanks -Pushpasis _______________________________________________ spring mailing list [email protected]<mailto:[email protected]> https://www.ietf.org/mailman/listinfo/spring _______________________________________________________________________ __ ________________________________________________ Ce message et ses pieces jointes peuvent contenir des informations confidentielles ou privilegiees et ne doivent donc pas etre diffuses, exploites ou copies sans autorisation. Si vous avez recu ce message par erreur, veuillez le signaler a l'expediteur et le detruire ainsi que les pieces jointes. Les messages electroniques etant susceptibles d'alteration, Orange decline toute responsabilite si ce message a ete altere, deforme ou falsifie. Merci. This message and its attachments may contain confidential or privileged information that may be protected by law; they should not be distributed, used or copied without authorisation. If you have received this email in error, please notify the sender and delete this message and its attachments. As emails may be altered, Orange is not liable for messages that have been modified, changed or falsified. Thank you. . _______________________________________________ spring mailing list [email protected]<mailto:[email protected]> https://www.ietf.org/mailman/listinfo/spring
_______________________________________________ spring mailing list [email protected] https://www.ietf.org/mailman/listinfo/spring
