Re: [IPv6] [spring] Subject: Mandating SRH when using C-SIDs (draft-ietf-spring-srv6-srh-compression)

Antoine FRESSANCOURT <> Fri, 05 April 2024 12:53 UTC

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From: Antoine FRESSANCOURT <>
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Thread-Topic: [spring] Subject: Mandating SRH when using C-SIDs (draft-ietf-spring-srv6-srh-compression)
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Subject: Re: [IPv6] [spring] Subject: Mandating SRH when using C-SIDs (draft-ietf-spring-srv6-srh-compression)
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After reading RFC 8754 and RFC 8986 together with the draft (version 14), it seems to me that the cases when the SRH will be omitted are quite limited, and will happen among nodes sharing the same locator block. We can assume that, in such cases, nodes exchanging packets carrying a C-SID without SRH will be managed by a single entity and that this entity can check whether some middlebox infer with packet relaying. 

Then we could modify the text to mention that, if such an inference is detected, the packet should use a SRH. In my view, being clear about potential issue related with omitting the SRH and giving an alternative is enough, and gives some freedom to people willing to use C-SID without SRH in their context.

Best regards,

Antoine Fressancourt

-----Original Message-----
From: spring <> On Behalf Of Alvaro Retana
Sent: jeudi 28 mars 2024 13:06
To: SPRING WG List <>
Cc: 6man <>;
Subject: [spring] Subject: Mandating SRH when using C-SIDs (draft-ietf-spring-srv6-srh-compression)

Focusing on the C-SID draft, some have suggested requiring the presence of the SRH whenever C-SIDs are used. Please discuss whether that is the desired behavior (or not) -- please be specific when debating the benefits or consequences of either behavior.

Please keep the related (but independent) discussion of requiring the SRH whenever SRv6 is used separate. This larger topic may impact several documents and is better handled in a different thread (with 6man and spring included).


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