Re: [spring] Is srv6 PSP a good idea

Fernando Gont <fernando@gont.com.ar> Wed, 26 February 2020 16:55 UTC

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To: Dirk Steinberg <dirk@lapishills.com>
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From: Fernando Gont <fernando@gont.com.ar>
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Date: Wed, 26 Feb 2020 13:54:44 -0300
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Subject: Re: [spring] Is srv6 PSP a good idea
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On 26/2/20 12:57, Dirk Steinberg wrote:
> Hi Fernando,
> 
> adding to my own comment and to be more specific:
> 
> The existing RFCs are very clear in their wording that
> the node identified in the Destination Address field of
> the  IPv6 header is free to do whatever it desires with
> the packet it just received. After all, the packet was
> addressed specifically to that node.
> 
> These nodes are called segment endpoint nodes in SRv6.
> 
> Only nodes that are *NOT* identified in the DA are
> prohibited from making any changes.
> This should be very clear, even if you seem to
> wish that IPv6 had been defined differently.

Are you saying that IPv6 allows for in the network header insertion/removal?

If so, please tell me how AH, Path-MTU Discovery, and ICMPv6 error 
reporting works -- all very basic functions of IPv6.

IPv6 is an end to end protocol. With RH you change the DA on the flight, 
because routing only works based on the DA -- there's no other way to 
specify waypoints.

If you claim otherwise, that can be, at best, a major misunderstanding 
of how IPv6 works.

Thanks,
-- 
Fernando Gont
e-mail: fernando@gont.com.ar || fgont@si6networks.com
PGP Fingerprint: 7809 84F5 322E 45C7 F1C9 3945 96EE A9EF D076 FFF1