Subject: [rrg] [ILNP] What to do when Locator Updates are lost

From: Stephane Bortzmeyer <[email-masked]>
Date: Mon, 16 Jul 2012 15:48:31 +0200

Another philosophical question on ILNP.  draft-irtf-rrg-ilnp-eng-06
and draft-irtf-rrg-ilnp-icmpv6-06 do not mention what to do when a
Locator Update (which is, after all, just an ordinary ICMP message) is
lost. There is no mention of retrying (DNS-style). Retrying could be
triggered by the absence of a Locator Update Acknowledgement but both
drafts say nothing about the use of Acknowledgements.

draft-irtf-rrg-ilnp-noncev6-06 says:

   Hence, the node that has had all previously valid Locators become
   invalid MUST include the Nonce Option with the appropriate nonce
   value in all packets (data or otherwise) to all correspondents
   for at least 3 round-trip times for each correspondent. [...] This
   'gratuitous authentication' ensures that the correspondent can authenticate
   any received packet, even if the ICMP Locator Update control
   message arrives and is processed AFTER some other packet using
   the new Source Locator(s). 

But this covers only the case where the Locator Update is delayed, not
the case where it is lost. Or should a node update its ILCC when
receving these 'gratuitous authentication' packets with a new Source
Locator? I do not find any explicit mention of it.