Re: M2PA Alignment Clarification

Mark,

Well, if the implementation does not follow the recommendations
of RFC 4165 section 4.1.8, then there will be a problem.

If, at the receiver, you should wait until it can be determined
that no messages are outstanding for stream 0 before reading data
messages on stream 1, per section 4.1.8.  When you read an SLTM
and have a missing TSN, as all M2PA messages are sent ordered,
you can easily detect that there is a missing message from stream 0.

Per 4.1.8, your receiver should wait until the link status stream
messages are read before processing messages read from stream 1.

Therefore, if you make your receiving implementation follow 4.1.8
to the letter, then you will not have a problem: it will wait until
all proving messages have been received before processing the SLTM.

--brian


Davidson, Mark wrote:                    (Wed, 04 Oct 2006 07:21:45)
> Brian,
> 
> I agree that if ALL senders wait for the last LSP to be acked by SCTP
> before sending LSR/DATA then the problem is fixed (though I dislike
> munging the layers in this way).  But the original problem is one for
> the receiver, not the sender.  I.e., the receiver cannot guarantee that
> the far end follows this procedure.  Changing what is sent, doesn't help
> guarantee what is received.  We don't get to assume the same vendor on
> both ends.  So the problem remains.
> 
> -Mark Davidson
> 

-- 
Brian F. G. Bidulock
[email protected]
http://www.openss7.org/