[ebxml-cppa-negot] Re: Negotiation pattern, transactions, CPPA

[Martin W Sachs <mwsachs@us.ibm.com>]

Bob,

In my mind, we want to permit either party to be able make an offer or
counter offer while avoiding the race conditions.  Your (2) is interesting.
If I send you a counter-pending response, I am telling you that I want the
ball to initiate tne next transaction.  I had not thought about that
possibility.

As to (1), we can't avoid that but we still need to figure out who gets the
ball next if the two parties have both each other sent initial requests.

Regards,
Marty

*************************************************************************************

Martin W. Sachs
IBM T. J. Watson Research Center
P. O. B. 704
Yorktown Hts, NY 10598
914-784-7287;  IBM tie line 863-7287
Notes address:  Martin W Sachs/Watson/IBM
Internet address:  mwsachs @ us.ibm.com
*************************************************************************************


                                                                                                                                 
                      bhaugen                                                                                                    
                      <linkage@interacc        To:       Martin W Sachs/Watson/IBM@IBMUS                                         
                      ess.com>                 cc:       ebtwg-bps@lists.ebtwg.org, ebxml-cppa-negot@lists.oasis-open.org        
                                               Subject:  Re: Negotiation pattern, transactions, CPPA                             
                      03/05/2002 01:42                                                                                           
                      PM                                                                                                         
                                                                                                                                 
                                                                                                                                 



From: Martin W Sachs
> The race condition issue is simply this:  Some protocols might get to
a
> point where the two parties, more or less simultaneously, send request
> messages to each other.  The two requests might be conflicting
proposals
> for some particular aspect of the CPPA being negotiated.  It that
point, it
> may not be clear whose proposal takes precedence.  That in turn could
lead
> to conflicting responses, at which point the state of the draft CPPA
might
> be unclear.

1. How is this different from the situation where two parties,
more or less simultaneously, kick off the initial request
messages to each other?

2. I think of the negotiation pattern as a game, where
the trading partners take turns.  Strictly.  When I send
you an offer, you must respond with either acceptance,
rejection or counter-pending.  You cannot send a counter-
offer without first sending the counter-pending response
and receiving my ack.  Etc.

3. If that is too strict for you (you really want to allow
anybody to make an offer at any time in the collaboration)
then:  if you use the transaction protocol, each offer starts
a separate transaction.  It's the same as #1 above.
(But I wouldn't do that...)

What am I missing?

-Bob Haugen