Re: [mpls] MPLS extension header

[" 徐小虎(义先) " <[e-mail]>]

Please see my response inline.


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From:Haoyu song <[e-mail]>
Send Time:2018年8月10日(星期五) 03:28
To:徐小虎(义先) <[e-mail]>; [e-mail] <[e-mail]>
Subject:RE: [mpls] MPLS extension header


For example, no support of network programming in MPLS-SR 

[Xiaohu] What concrete network programming capability is expected for MPLS-SR?

For another example, no support of metadata if MPLS-SR is used for SFC J

[Xiaohu] As for how metadata is carried in the MPLS-SR-based SFC mechanism, please see section 7.1 of https://tools.ietf.org/html/draft-xuclad-spring-sr-service-chaining-01.

Xiaohu

Haoyu

From: mpls [mailto:[e-mail]] On Behalf Of ???(??)
Sent: Wednesday, August 08, 2018 8:37 PM
To: 徐小虎(义先) <[e-mail]>; [e-mail]
Subject: Re: [mpls] MPLS extension header

By the way, I just noticed the following text in your draft:

"
   Segment Routing:  MPLS extension header can support the
      implementation of a new flavor of the MPLS-based segment routing,
      with better performance and richer functionalities.  The details
      will be described in another draft."
 
What's the rationale of implementing a new flavor of MPLS-based Segment Routing? In other words, what potential issues with the current MPLS-SR are to be addressed by the MPLS extension header-based MPLS-SR variation?
 
Best regards,
Xiaohu
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From:徐小虎(义先) <[e-mail]>
Send Time:2018年8月9日(星期四) 10:56
To:mpls <[e-mail]>; [e-mail] <[e-mail]>
Subject:Re: [mpls] MPLS extension header

Hi Haoyu,

I believe it's worthwhile to introduce an MPLS payload indicator into MPLS so as to support various MPLS payload types in a long run. However, I wonder whether the mechanism as described in (https://tools.ietf.org/html/draft-xu-mpls-payload-protocol-identifier) has met this demand.

Best regards,
Xiaohu
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From:Haoyu song <[e-mail]>
Send Time:2018年8月9日(星期四) 06:24
To:[e-mail] <[e-mail]>
Subject:[mpls] MPLS extension header

Dear all,

In IETF102 we presented the idea of MPLS extension header and received a lot of discussion. We have updated the draft to reflect the feedbacks we received.  
It seems most people agree that we need extension headers (EH) to support multiple emerging in-network services, but there could be debate on how to indicate the existence of the EHs.
In the document we provide our investigations and suggestions but we do want to see your opinion. Hopefully we can achieve a consensus before IETF103.   
Thank you in advance for your help!

https://www.ietf.org/id/draft-song-mpls-extension-header-01.txt

Best regards,
Haoyu