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RE: [EFM] Should There Be A Sequence Number In Variable Request/R esp onse PDUs?

Hi John,
I agree, calling it sequence number may mislead people to think it has to be incremented in certain ways, or may imply a state of connection. I like your idea of calling it a correlater.
Further, I agree that such a field should be set by the requester to any value it pleases and the responder should simply return it untouched, and without using the value in any way.
Thanks for responding.
Yonhong Ren
Appian Communications
-----Original Message-----
From: John Messenger []
Sent: Thursday, August 14, 2003 5:36 AM
To: 'Yonghong Ren'; ''
Subject: RE: [EFM] Should There Be A Sequence Number In Variable Request/R esp onse PDUs?

At least the responses contain the information on which values are being returned, so to some extent one can simply use that as a kind of correlator.
However, I agree that a correlator field might well be useful to correlate requests and responses, but I'd recommend calling it a correlator rather than a sequence number, and avoid any language requiring it to be incremented in each request etc.  Simply say that the correlator from the variable request PDU should be returned in each resulting variable response PDU - then, anyone who wanted to, could set it to a unique value, and anyone else could just set it to zero and ignore it when returned.
Does anyone else have an opinion?
    -- John
-----Original Message-----
From: Yonghong Ren []
Sent: 13 August 2003 21:25
To: ''
Subject: [EFM] Should There Be A Sequence Number In Variable Request/Resp onse PDUs?

Variable Request and Response PDUs don't have a sequence number field.
If one is allowed to send multiple outstanding Variable Requests, then how is to match a response to its corresponding request? Should not we introduce a sequence number? Sure, to some extent one could match them by looking at what variables are included, but it's not a sure way.
If the intention is not to allow more than one Variable Request at a time, which I think is reasonable in order to keep the OAM operation simple, then a note to that effect in the standard would be nice.
Your comments are welcome and appreciated. 
Yonghong Ren
Appian Communications