[GRAAP-WG] Modification to the wiki Page on Renegotiating anestablished Agreement

[Karl Czajkowski]

On Aug 24, Toshiyuki Nakata modulated:
> Karl:
> thank you very much for the excellent summary.
> (which I must  admit I would need a week to really digest.).
> 
> One thing that I (and I think you also pointed out ) was that that 
> in the case of AR not agreeing, there were not enough hints
> for the AI to initiate another request..
> 
> Any comments on this?
> 

Well, my practical view, keeping in mind bounded-rationality systems,
is that if the template was insufficient to guide you to an acceptable
agreement offer, then a "hint" would not fair any better.  Either the
advertiser announces its policies/restrictions in detail sufficient to
create an agreement, or it does not.  Why would it reveal more
information on the next iteration?  If you're trying to address
intelligent parties who do bluffing and bartering, then your problem
is out of scope for WS-Agreement...

Another intractable problem is that the resource manager making the
decision may not even be able to formulate a specific reason for "why
it didn't match", e.g. in a scheduler that is matching many properties
at once against a dynamic load of competing requests, it is not
necessarily easy to determine what would need to change to make a
request get handled above other requests. Furthermore, it would have
race conditions since the dynamic load may be different by the time
the next offer arrives.

So I think in practice, an automated WS-Agreement initiator is going
to operate with some narrowly-defined commodity offers and try
fallback, retry, and fail-over among responders.  If this fails,
offline analysis and problem determination will be required to
understand what went wrong, and how to improve templates and offering
systems to avoid these doomed offers.


karl

-- 
Karl Czajkowski
Software Architect

Univa Corporation
1001 Warrenville Road, Suite 550
Lisle, IL 60532

karlcz at univa.com
www.univa.com
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