RE: [spring] Is srv6 PSP a good idea

Andrew Alston <> Wed, 26 February 2020 14:15 UTC

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From: Andrew Alston <>
To: Sander Steffann <>, Robert Raszuk <>
CC: "" <>, 6man WG <>
Subject: RE: [spring] Is srv6 PSP a good idea
Thread-Topic: [spring] Is srv6 PSP a good idea
Date: Wed, 26 Feb 2020 14:15:22 +0000
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+1 Sander.

Furthermore - if indeed that is the contention - then - I suggest you move the whole thing out of SPRING - I quote from the SPRING charter:

The Source Packet Routing in NetworkinG (SPRING) Working Group is the home of Segment Routing (SR) using MPLS (SR-MPLS) and IPv6 (SRv6).

Relevant portion in bold.

You can claim that SRv6 is a new routing header - you cannot claim that it is not part of IPv6 - the IPv6 base header is maintained - you are adding a routing header - done/done - no point even entertaining this line of thought any further


From: spring <> On Behalf Of Sander Steffann
Sent: Wednesday, 26 February 2020 16:49
To: Robert Raszuk <>
Cc:; 6man WG <>
Subject: Re: [spring] Is srv6 PSP a good idea

Hi Robert,

> Regardless if folks agree or not with that SRv6 is a new data plane. SRv6 != IPv6 that's obvious.
> It also does not attempt to *extend* IPv6. It reuses some IPv6 elements and makes sure non SRv6 nodes can treat the packets as vanilla IPv6, but that's it. With that in mind all of this going back and forth between SPRING and 6MAN to me is triggered by wrong positioning of SRv6 as a new transport.

This is completely bogus. SRv6 is not a new L3 protocol that just happens to be compatible with IPv6. That is insane BS.

> Sure if SRv6 would be extending IPv6 then updates to RFC8200 would be needed - but here RFC8200 should at best be informative reference. I am not even sure why SRH needs to be 6MAN RFC. IETF is designed to build and improve prior art not be locked by it.

Because you are building SRv6 on IPv6, plain and simple.


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