Re: [spring] Updating the SPRING WG Charter

[Alexander Vainshtein <[e-mail]>]

Robert,
I think that you have cut the quoted text from the Segment Routing Architecture<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-15> draft a bit too short. The complete fragment says:

   Where possible, it is recommended that identical SRGBs be configured
   on all nodes in an SR Domain.  This simplifies troubleshooting as the
   same label will be associated with the same prefix on all nodes.  In
   addition, it simplifies support for anycast as detailed in
   Section 3.3<https://tools.ietf.org/html/draft-ietf-spring-segment-routing-15#section-3.3>.

In other words,  the Segment Routing Architecture draft:

-          Does not consider identical SRGBs on all nodes in an SR domain as a requirement.

-          Explains that such configuration, if used, simplifies troubleshooting and support of anycast segments. With regard to the latter, please note that the Anycast Segments<https://tools.ietf.org/html/draft-ietf-spring-mpls-anycast-segments-02> draft defines a mechanism that facilitates usage of anycast segments in an environment with different SRGBs on different nodes.


Therefore, from my POV, domain-wide labels have been purged (for quite some time now) from the SR-MPLS architecture. I do not think that they should be re-introduced.

My 2c,
Sasha

Office: [phone]
Cell:      [phone]
Email:   [e-mail]

From: [e-mail] [mailto:[e-mail]] On Behalf Of Robert Raszuk
Sent: Friday, June 8, 2018 11:44 PM
To: Alexander Vainshtein <[e-mail]>
Cc: Paul Mattes <[e-mail]>; [e-mail]; Xiejingrong <[e-mail]>; Michael McBride <[e-mail]>; Rob Shakir <robjs=[e-mail]>; Zafar Ali (zali) <[e-mail]>; Eric C Rosen <[e-mail]>; Voyer, Daniel <[e-mail]>
Subject: Re: [spring] Updating the SPRING WG Charter

Folks,

The only reason why SR-MPLS architecture is using indexes as opposed to domain wide labels is a claim from few folks that possibly in some networks deployed platforms would not be able to use the same global label block for SR.

So SR-MPLS architecture agreed to use index to offset possible per platform label block.

That said number of real deployment do use global (domain wide) identical block on all nodes and that is the actual recommendation from section 3.1.2 of SR architecture

"Where possible, it is recommended that identical SRGBs be configured on all nodes in an SR Domain."

But none of this really matters for the discussion at hand. Embedding instruction for specific function can be easily done within programmed domain wide index offset.

Best,
R.


On Fri, Jun 8, 2018 at 10:21 PM, Alexander Vainshtein <[e-mail]<mailto:[e-mail]>> wrote:
Robert, Paul and all,
I concur with Paul.
Domain-wide labels have been successfully purged from SR-MPLS for quite some time now, and, from my POV this purge is irreversible now.
My 2c.
Thumb typed by Sasha Vainshtein



___________________________________________________________________________

This e-mail message is intended for the recipient only and contains information which is 
CONFIDENTIAL and which may be proprietary to ECI Telecom. If you have received this 
transmission in error, please inform us by e-mail, phone or fax, and then delete the original 
and all copies thereof.
___________________________________________________________________________