Re: Compatibility with SRH requirement (was Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)")

Robert Raszuk <> Sat, 30 May 2020 09:17 UTC

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From: Robert Raszuk <>
Date: Sat, 30 May 2020 11:17:06 +0200
Message-ID: <>
Subject: Re: Compatibility with SRH requirement (was Re: Adoption Call for "The IPv6 Compact Routing Header (CRH)")
To: Tom Herbert <>
Cc: James Guichard <>, Bob Hinden <>, IPv6 List <>
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Routing information and protocol and node capabilities are by design
ephemeral and are maintained only till supplier is still alive.

If such state would be kept in the network upon reboot (modulo GR restart
procedures) we would end up running completely broken networks.

So no other nodes can not keep memory of previously advertised capabilities
before reboot or upgrade and keep using it based on
historical advertisements.


Suppose if a node advertises it is compression capable but at some
> point the administrator downgrades the software to no longer support
> compressed SIDs and reboots. When the node comes back what prevents
> other nodes from sending compressed SIDs to the node based on the fact
> the node previously advertised them but no longer does?