Stephane -

Implementations based on the drafts that currently exist advertise a topology 
independent SRGB. A SID which is advertised in a specific MT Prefix 
Reachability advertisement is interpreted as an index into the topology 
independent SRGB. This is NOT compatible with an implementation which is 
written assuming that a SID is an index into a topology specific SRGB. So the 
introduction of topology specific SRGBs would have to be supported network-wide 
before it could be deployed. Sub-TLVs cannot resolve this incompatibility.

   Les


> -----Original Message-----
> From: spring [mailto:[email protected]] On Behalf Of
> [email protected]
> Sent: Wednesday, August 26, 2015 12:25 AM
> To: Pushpasis Sarkar; Les Ginsberg (ginsberg); Uma Chunduri; Peter Psenak
> (ppsenak); Eric Rosen; SPRING WG
> Subject: Re: [spring] SRGBs, indexes, and topologies within a domain
> 
> Hi Pushpasis,
> 
> I just want to remember that the discussion is not only for MT, but there was
> also a thread for per algorithm SRGB (as presented in Prague). IMO, there
> must be some consistency in the choice we do.
> Regarding encoding nothing is impossible (as example a new subTLV can be
> created ensuring backward compatibility).
> I would say let's first have a consensus of what is good to do independently
> of the encoding.
> 
> Best Regards,
> 
> -----Original Message-----
> From: Pushpasis Sarkar [mailto:[email protected]]
> Sent: Wednesday, August 26, 2015 07:36
> To: Les Ginsberg (ginsberg); Uma Chunduri; LITKOWSKI Stephane SCE/IBNF;
> Peter Psenak (ppsenak); Eric Rosen; SPRING WG
> Subject: Re: [spring] SRGBs, indexes, and topologies within a domain
> 
> Hi Les,
> 
> 
> 
> 
> On 8/26/15, 7:13 AM, "Les Ginsberg (ginsberg)" <[email protected]>
> wrote:
> 
> >[Les:] Topology specific SRGBs requires a specification change for the IGPs.
> The new advertisements are NOT backwards compatible w existing
> implementations. So we cannot simply say "do what you please".
> >Peter has repeatedly made this point - and also pointed out that since the
> prefix advertisements as currently defined in the IGP drafts includes
> topology identifiers including the topology identifier in the SRGB
> advertisement is redundant.
> [Pushpasis] Why not add a MT-SR_Capability Sub/TLV then? That way it
> won’t break backward compatibility?
> 
> Thanks
> -Pushpasis
> 
> __________________________________________________________
> __________________________________________________________
> _____
> 
> 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]
> https://www.ietf.org/mailman/listinfo/spring
_______________________________________________
spring mailing list
[email protected]
https://www.ietf.org/mailman/listinfo/spring

Reply via email to