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Re: NEW ISSUE 4130: Ignorable assertions must be ignored

From: Sergey Beryozkin <sergey.beryozkin@iona.com>
Date: Mon, 8 Jan 2007 18:35:54 -0000
Message-ID: <019a01c73353$d4cdaea0$3901020a@sberyoz>
To: "Ashok Malhotra" <ashok.malhotra@oracle.com>, <public-ws-policy@w3.org>
Hi

"- ASSERTIONS THAT THE OTHER PARTY SHOULD NEVER SEE
Such as logging.  These are private to my implementation.
Glen: Such assertions should be removed prior to intersection and never exposed to the other party.
Ashok:  They can be included in the policy and always 'ignore' d."

S.B. Ashok what you're suggesting is exactly what we were trying to pursue with our wsp:local proposal, without success :-). We wanted a standard attribute which can be used to mark private assertions (would be useful for writing generic tools, etc), furthermore we were agreeing that such assertions must be stripped of, but ignored by requesteres if leaked (inadvertently or due to some constraints). 
Now that we have wsp:ignorable I don't see a way of getting back...So I agree with Glen.

As was noted before, you can now use a lax mode if you want your provider assertions be ignored. Otherwise, why to expose assertions which need to be always ignored ? Assertions are for requesters.

"
- ASSERTIONS THAT CANNOT BE MATCHED BY MACHINE
A: I think these are useful to include in policies for advertising.
For example, legal or privacy policies.  Users cannot match on these but will look at them and decide whether to use a particular service or not based on their contents.
These too must be always 'ignore' d during intersection.
G: Such assertions should not be included in policies but, rather, included in some other metadata bucket.
A: But we have not defined any other metadata buckets. "

S.B. I agree that these are useful to include in policies for advertising. Two options :
* Make these assertions as "ignorable" and use the lax mode to handle such policies. This will require a smart requester UI tool which will offer users a chance to vote on "ignorable" provider assertions which have not been understood during the intersection.
* As Tom noted, you can use a strict mode too. This will require requesteres though to be aware of these assertions in advance.

"- ASSERTIONS THAT THE OTHER PARTY MAY BE ABLE TO MATCH
G: If he can match the assertions, great!  If not, he should be able to proceed even if he cannot match.  This is the rationale for lax and strict matching.
A: I accept this usecase but that's not what I was thinking of."

So if you agree with Glen here then I'm not qute sure what exactly is your scenario...

Thanks, Sergey





Glen Daniels and I had a chat about 'ignorable'.

It turns out, not surprisingly, that we had different usecases in mind
and different ideas as to how they should be handled.

Here is a summary of our positions.  Please respond if you have views on
them.

Glen, please correct me if I have misrepresented your positions.

- ASSERTIONS THAT THE OTHER PARTY SHOULD NEVER SEE
Such as logging.  These are private to my implementation.
Glen: Such assertions should be removed prior to intersection and never exposed to the other party.
Ashok:  They can be included in the policy and always 'ignore' d.

- ASSERTIONS THAT CANNOT BE MATCHED BY MACHINE
A: I think these are useful to include in policies for advertising.
For example, legal or privacy policies.  Users cannot match on these but will look at them and decide whether to use a particular service or not based on their contents.
These too must be always 'ignore' d during intersection.
G: Such assertions should not be included in policies but, rather, included in some other metadata bucket.
A: But we have not defined any other metadata buckets.

- ASSERTIONS THAT THE OTHER PARTY MAY BE ABLE TO MATCH
G: If he can match the assertions, great!  If not, he should be able to proceed even if he cannot match.  This is the rationale for lax and strict matching.
A: I accept this usecase but that's not what I was thinking of.

All the best, Ashok

> -----Original Message-----
> From: public-ws-policy-request@w3.org [mailto:public-ws-policy-
> request@w3.org] On Behalf Of Ashok Malhotra
> Sent: Tuesday, January 02, 2007 6:37 AM
> To: public-ws-policy@w3.org
> Subject: NEW ISSUE 4130: Ignorable assertions must be ignored
> 
> 
> 
> 
> Title
> 
> Ignorable assertion must be ignored
> 
> Description
> 
> At the last f2f meeting the WS-Policy WG agreed to add an attribute called
> 'ignorable' to the WS-Policy assertion syntax.  We think this is a step in
> the right direction.  The WG, however, blunted the effect of this change
> by
> allowing the ignorable attribute to be ignored during policy intersection
> by
> allowing two intersection modes one of which honors the ignorable
> attribute and the other which ignores it.
> 
> We argue this creates a problem as the parties attempting to agree on a
> policy alternative may use different forms of the intersection algorithm
> and come up with different solutions.  A standard that allows such
> variation is not very useful.
> 
> We suggest that the policy intersection algorithm be changed so that
> assertions marked ignorable are always ignored.
> 
> Justification
> 
> See above.
> 
> Target
> 
> WS-Policy Framework
> 
> Proposal
> 
> 1. In section 4.5 Policy Intersection, add a third bullet after the first
> two bullets that says:
> o Assertions with ignorable = 'true' are ignored in during policy
> intersection.
> 
> 2. Remove the first bullet, including its sub-bullets from the second set
> of 2 bullets.
> 
> 3. Add an ignorable assertion to the following example.
> 
> 
> 
> 
Received on Monday, 8 January 2007 18:34:58 GMT

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