Hi; For the case I'm focused on -- namely a BES service exposing what it has available -- one can argue that the service already knows who the requestor is because of standard WS-Security. So it can choose to tailor its answers accordingly if it wants to. By-the-way, I'm now thinking that maybe the simplest case for describing available resources is actually to specify a very small number of aggregate values, such as number of compute nodes that are available, rather than specifying an array of jsdl documents. What do you think? Marvin. -----Original Message----- From: Donal K. Fellows [mailto:donal.k.fellows@manchester.ac.uk] Sent: Friday, June 09, 2006 3:20 AM To: Karl Czajkowski Cc: Marvin Theimer; JSDL Working Group; ogsa-bes-wg@ggf.org; Ed Lassettre; Ming Xu (WINDOWS) Subject: Re: [jsdl-wg] Questions and potential changes to JSDL, as seen from HPC Profile point-of-view Karl Czajkowski wrote:
One thing Donal mentioned which I would like to emphasize:
The discovery ought to be "what types of job are acceptable" and not what resources are there. Or rather, the latter is part of some administrative interface which is misleading for job-submitting users and middleware.
This may sound pedantic, but it will be crucial for interop. The discovery has to capture realistic operating policy, and not just give enticing catalogues of resources which can never be combined in a single request!
I'm in strong agreement with Karl here (yes, it does happen from time to time! ;-)) I'd go further and state that a resource that I cannot access should not exist at all. Well, at least from my perspective. A side effect of this is that resource discovery and selection *must* be aware of the identity of the user for whom a resource is being chosen (and that in turn means that the EPS spec will have to make non-trivial statements about security. Yuck.) Donal.