Re: [spring] Penultimate Segment Popping and RFC8200 (Was Re: We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping))

Robert Raszuk <> Tue, 10 December 2019 23:39 UTC

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From: Robert Raszuk <>
Date: Wed, 11 Dec 2019 00:39:18 +0100
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To: Fernando Gont <>
Cc: Bruno Decraene <>, Ron Bonica <>, SPRING WG <>, "" <>, Andrew Alston <>, rtg-ads <>, Bob Hinden <>, Brian E Carpenter <>, Ole Troan <>, Suresh Krishnan <>
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Subject: Re: [spring] Penultimate Segment Popping and RFC8200 (Was Re: We don't seem to be following our processes (Re: Network Programming - Penultimate Segment Popping))
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Dear Fernando,

Allow me to make something very clear here.

And, since we are at it, please let me know if IPv6 is and end to end
> protocol. And, if it is, how does that e2e-ness work with inserting and
> removing EHs on the path to the ultimate destination of a packet.

The dream of IPv6 flat end to endless is long gone if it ever was
even real.

There is no end to end IPv6 or for that matter IPv4 delivery today across
any network. Regardless if this is private or public network of any
reasonable size and service portfolio.

Some form of encapsulation or tunneling is used in enterprises, in ISPs, in
SPs or even in largest public clouds.

So if you think that you can send an IPv6 packet and that this packet will
be delivered to its final destination without any encapsulation on the way
- this is just unreal. And the sooner you and others like you realize this
the better for everyone.

Think about L3VPNs reachability segmentation, think about SFC/NSH, think
about L2 transport emulation of your circuits, think about seamless
mobility, LISP  ...

Just a tiny reality check,