[tsvwg] SCTP: association restart in the SHUTDOWN_PENDING or SHUTDOWN_SENT state

Jeff Morriss <jeff.morriss.ws@gmail.com> Tue, 24 February 2015 22:39 UTC

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Date: Tue, 24 Feb 2015 17:39:26 -0500
From: Jeff Morriss <jeff.morriss.ws@gmail.com>
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Subject: [tsvwg] SCTP: association restart in the SHUTDOWN_PENDING or SHUTDOWN_SENT state
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Hi folks,

RFC 4960's section 5.2.4 talks about association restart (action (A)). 
My reading is that restart can happen in any state other than CLOSED.

But if the association is in the SHUTDOWN_PENDING or SHUTDOWN_SENT state 
then I'm not sure it makes sense to allow the association to restart: 
from the API perspective the application has called shutdown() and/or 
close() (possibly with SO_LINGER set) so it's unlikely to be able to 
handle a restarted association.

I saw a patch to one SCTP implementation on the web because it needed to 
add logic to shut down the association when this happens (actually the 
patch I saw only handled the SHUTDOWN_PENDING state).  Should the RFC 
explicitly cover this scenario?

Regards,
-Jeff