Subject: M2PA interop - LPO related questions

From: Vladi Arbetov <[email-masked]>
Date: Thu, 4 Oct 2001 19:48:33 +0200

Waine,

The questions relating to the LPO was raised during the today's M2PA
interop conference call. 

Test B3: should the Test Driver stop the data transmission before
entering the LPO and continue the data transmission after LPO recovery?
If not - that should M2PA do getting the data message from the upper
layer while in LPO state? 

Test B5 says: "Establish a link and begin data transmission. Tell one
side that it is in local processor outage. Remain in that state until
the other side Stops (ABORT) the link." The same in B9.
As far as I understand - Processor Outage shouldn't cause to this. In
SS7 - changeover due to Processor outage is done by timer and not by
link failure.
What should cause the other side to Stop (ABORT) the link? Should it be
a manual action?

My opinion is:
LPO indicates the unavailability of the upper layer to the M2PA layer.
Getting the message from the upper layer while LPO is abnormal and can
indicate its availability to M2PA. This can happen when Local Processor
Outage Recovered Request from the upper layer somehow wasn't treated
properly. It means exists misfit the statuses of the M2PA and upper
layer.
a) Discarding the message just keeps the status misfit on and cause to
discarding all follows messages.
b) Sending the message to peer without LPO reset probably will cause
just to discarding the message later at the peer because the RPO status
and keeps the status misfit on.
c) Reset LPO and send data to peer - corrects the status misfit and
doesn't cause to message lost. 

Option c) looks to me as a proper action. 

Correct me if I'm wrong.

Thanks a lot in advance,

   Vladimir Arbetov
   Director, SS#7 Networking
   Airslide Systems Ltd.
   http://www.airslide.com/
   Tel +972-9-9709805 
   Fax +972-9-9709843
   Cell +972-54-416441

---
You are currently subscribed to sigtran as: [email-masked]
To unsubscribe send a blank email to [email-masked]