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RE: Are nested assertions part of the policy vocabulary?

From: Katy Warr <katy_warr@uk.ibm.com>
Date: Wed, 9 May 2007 15:19:32 +0100
To: Ram Jeyaraman <Ram.Jeyaraman@microsoft.com>, Ashok Malhotra <ashok.malhotra@oracle.com>
Cc: Bob Freund <bob@freunds.com>, Daniel Roth <Daniel.Roth@microsoft.com>, Anthony Nadalin <drsecure@us.ibm.com>, Maryann Hondo <mhondo@us.ibm.com>, "public-ws-addressing@w3.org" <public-ws-addressing@w3.org>, public-ws-addressing-request@w3.org, "public-ws-policy@w3.org" <public-ws-policy@w3.org>, Sergey Beryozkin <sergey.beryozkin@iona.com>
Message-ID: <OF515E116D.05321EC4-ON802572D6.004DA19F-802572D6.004EB1FC@uk.ibm.com>
Ashok

As Ram states - we agreed on solution G. 

In order to express full WS-Addressing support (and intersection with all 
WS-Addressing clients), a service provider would need to specify:
<policy>
    <wsam:UsingAddressing>
       <policy/>
    </wsam:UsingAddressing>
</policy>
 <policy>
    <wsam:UsingAddressing>
         <policy>
              <wsam:AnonymousResponses>
          </policy>
    </wsam:UsingAddressing>
</policy
 <policy>
    <wsam:UsingAddressing>
         <policy>
              <wsam:NonAnonymousResponses>
          </policy>
    </wsam:UsingAddressing>
</policy>
As you say, the empty assertion allows for replyTo=anon and faultTo= 
nonAnon (or vice-versa) in a single message.

Best regards
Katy




Ram Jeyaraman <Ram.Jeyaraman@microsoft.com> 
Sent by: public-ws-addressing-request@w3.org
09/05/2007 04:09

To
Ashok Malhotra <ashok.malhotra@oracle.com>
cc
"public-ws-addressing@w3.org" <public-ws-addressing@w3.org>, 
"public-ws-policy@w3.org" <public-ws-policy@w3.org>, Daniel Roth 
<Daniel.Roth@microsoft.com>, Sergey Beryozkin <sergey.beryozkin@iona.com>, 
Bob Freund <bob@freunds.com>, Maryann Hondo <mhondo@us.ibm.com>, Anthony 
Nadalin <drsecure@us.ibm.com>
Subject
RE: Are nested assertions part of the policy vocabulary?






Ashok,
 
> but this seems to be the behavior that WS-Addressing folks want.
 
I believe the WS-Addressing WG agreed that proposal G satisfies the 
WS-Addressing use case sufficiently during the penultimate WG call [1][2]. 
Currently, the WS-Addressing WG is just waiting for feedback [3] from the 
WS-Policy WG, before entering the Last Call stage.
 
Section 3.1.6 [4] of the WS-Addressing specification provides guidance [5] 
on policy intersection and sufficiently warns the consumer to carefully 
craft its policy alternatives so as to increase its chances of being 
compatible. So, a policy consumer should be able to successfully intersect 
as long as it is careful about maximizing its chances of intersection by 
following the guidance [4].
 
Thank you.
 
[1] http://www.w3.org/2002/ws/addr/7/04/23-ws-addressing-minutes.html
[2] http://www.w3.org/2002/ws/addr/7/04/02-ws-addressing-minutes.html
[3] http://lists.w3.org/Archives/Public/public-ws-policy/2007Apr/0094.html
[4] 
http://dev.w3.org/cvsweb/~checkout~/2004/ws/addressing/ws-addr-wsdl.html?content-type=text/html;%20charset=utf-8#usingintersection 

[5] ?The policy used by the client must be written carefully to avoid 
unexpected results.?
 
From: public-ws-addressing-request@w3.org 
[mailto:public-ws-addressing-request@w3.org] On Behalf Of Ashok Malhotra
Sent: Tuesday, May 08, 2007 2:30 PM
To: Daniel Roth; Sergey Beryozkin; Bob Freund; Maryann Hondo; Anthony 
Nadalin
Cc: public-ws-addressing@w3.org; public-ws-policy@w3.org
Subject: RE: Are nested assertions part of the policy vocabulary?
 
Hi Dan:
You made a very important point that I want to highlight.  You said:
?In some cases a single message may specify both an anonymous ReplyTo EPR 
and a non-anonymous FaultsTo EPR.  To satisfy this scenario you need to 
have some way of saying that addressing is fully supported without 
qualifications.?
 
By your final sentence I presume you are saying that
 
<policy>
    <wsp:Addressing>
         <policy/>
    </wsp:Addressing>
</policy>
 
means that addressing is fully supported without qualifications.   Is this 
correct?   If so, then the above policy should intersect successfully 
with, for example:
 
<policy>
    <wsp:Addressing>
         <policy>
              <wsp:AnonymousReplies/>
         <policy/>
    </wsp:Addressing>
</policy>
 
Do you agree?    We understand that this is not what the spec says but 
this seems to be the behavior that WS-Addressing folks want.
All the best, Ashok 

From: public-ws-addressing-request@w3.org 
[mailto:public-ws-addressing-request@w3.org] On Behalf Of Daniel Roth
Sent: Tuesday, May 08, 2007 1:26 PM
To: Sergey Beryozkin; Bob Freund; Ashok Malhotra; Maryann Hondo; Anthony 
Nadalin
Cc: public-ws-addressing@w3.org; public-ws-policy@w3.org
Subject: RE: Are nested assertions part of the policy vocabulary?
 
Hi Sergey,
 
> According to [1] If the provider uses <Policy/> then it means this 
provider will work with consumers using either anonymous or non-anonymous 
WSA qualifications. 
> And yet, the requester saying, by using <ws-addressing><Policy>
<AnonymousResponses/></Policy></ws-addressing>, that it wishes a provider 
to support 
> <AnonymousResponses/> will fail to intersect with the provider using 
<Policy/> which says that all types of responses are supported
 
A client that requires a service that supports anonymous responses will 
work with a service that supports all of addressing or just anonymous 
responses.  This means, the client should reflect that by including both 
alternatives in its policy.  The client policy with both alternatives 
intersects with the service policy and is specifically recommended in 
section 3.6.1 of the WS-Addressing Metadata spec.
 
> I'd even say that the empty nested ws-adressing <Policy> should be 
prohibited
 
In some cases a single message may specify both an anonymous ReplyTo EPR 
and a non-anonymous FaultsTo EPR.  To satisfy this scenario you need to 
have some way of saying that addressing is fully supported without 
qualifications.
 
I hope this helps.
 
Daniel Roth
 
 
From: Sergey Beryozkin [mailto:sergey.beryozkin@iona.com] 
Sent: Tuesday, May 08, 2007 2:25 AM
To: Bob Freund; Daniel Roth; Ashok Malhotra; Maryann Hondo; Anthony 
Nadalin
Cc: public-ws-addressing@w3.org; public-ws-addressing-request@w3.org; 
public-ws-policy@w3.org; public-ws-policy-request@w3.org
Subject: Re: Are nested assertions part of the policy vocabulary?
 
Hi
 
What confuses me is that it appears to be some inconsistency in the 
definition of what the empty nested Policy means in the scope of 
ws-addressing (see [1]), <ws-addressing><Policy/></ws-addressing> and the 
fact that this nested <Policy> does not intersect with a more qualified 
nested Policy such as <ws-addressing><Policy><AnonymousResponses/>
</Policy></ws-addressing>.
 
According to [1] If the provider uses <Policy/> then it means this 
provider will work with consumers using either anonymous or non-anonymous 
WSA qualifications. And yet, the requester saying, by using 
<ws-addressing><Policy><AnonymousResponses/></Policy></ws-addressing>, 
that it wishes a provider to support  <AnonymousResponses/> will fail to 
intersect with the provider using <Policy/> which says that all types of 
responses are supported...
 
I think what this means is using an all inclusive <Policy> alternative 
alone on the server is just not safe as it will cause compliant clients 
(say those wishing a provider to support <AnonymousResponses/>) to 
break...I'd even say that the empty nested ws-adressing <Policy> should be 
prohibited...Just have two nested policies, one allowing anonymous 
responses, another one allowing non-anonymous ones...That way a provider 
supporting all types of responses can list two alternatives and it will 
match all clients....
 
 
Thanks, Sergey
 
[1] 
http://lists.w3.org/Archives/Public/public-ws-policy/2007Apr/att-0094/WSAddrPolicyAlgerntiveGprime.htm
----- Original Message ----- 
From: Bob Freund 
To: Daniel Roth ; Ashok Malhotra ; Maryann Hondo ; Anthony Nadalin 
Cc: public-ws-addressing@w3.org ; public-ws-addressing-request@w3.org ; 
public-ws-policy@w3.org ; public-ws-policy-request@w3.org 
Sent: Tuesday, May 08, 2007 12:22 AM
Subject: RE: Are nested assertions part of the policy vocabulary?
 
+1
>From a plain reading of the WS-Policy intersection algorithm, these 
policies indeed are not compatible per the WS-Policy 1.5 framework CR 
spec.
-bob
 
From: public-ws-addressing-request@w3.org 
[mailto:public-ws-addressing-request@w3.org] On Behalf Of Daniel Roth
Sent: Tuesday, May 01, 2007 4:52 PM
To: Ashok Malhotra; Maryann Hondo; Anthony Nadalin
Cc: public-ws-addressing@w3.org; public-ws-addressing-request@w3.org; 
public-ws-policy@w3.org; public-ws-policy-request@w3..org
Subject: RE: Are nested assertions part of the policy vocabulary?
 
Hi Ashok, 
 
These two policies do not intersect and we believe this is verified in the 
test cases.  If Policy 2 is the policy for a requester then this 
intersection result may at first seem incorrect, so let me explain: 
 
It is incumbent on the Addressing authors to specify the semantics of the 
assertions.  The Addressing assertion expresses a requirement that 
WS-Addressing be used to exchange messages without qualifications.  The 
nested addressing assertions (which indicate additional characteristics of 
 the base WS-Addressing assertion)  qualify this semantic to say that 
either only non-anonymous responses are supported or that only anonymous 
responses are supported.  In the WS-Addressing protocol it?s the 
requester?s message that requests a specific kind of response ? anonymous, 
non-anonymous, or maybe even a mixture of the two. 
 
The thing to recognize is that if Policy 2 is a requester policy then it 
is incomplete in that it is not acknowledging that the base assertion also 
reflects support for anonymous responses.  The requester determines what 
response type should be used.  So, a client that needs non-anonymous 
responses will also work with a service that supports all of addressing. 
The client?s policy should reflect that  it is compatible with an endpoint 
that supports all of addressing by adding a second alternative.  This can 
be easily done using the Optional attribute as is shown in section 3.1.6 
in the WS-Addressing Metadata spec: 
              <Policy><Addressing ><Policy><AnonymousResponses 
wsp:Optional=?true? > </Policy></Addressing ></Policy> 
 
Note that if Policy 2 is a provider policy and Policy 1 is the requester 
policy ? where the requester wants unqualified support for addressing, but 
the provider only supports a specific response type ? then there is no 
issue.  These policies should not intersect and they don?t. 
 
We hope this helps. 
 
Daniel Roth
 
From: public-ws-policy-request@w3.org 
[mailto:public-ws-policy-request@w3.org] On Behalf Of Ashok Malhotra
Sent: Thursday, April 19, 2007 12:33 PM
To: Maryann Hondo; Anthony Nadalin
Cc: public-ws-addressing@w3.org; public-ws-addressing-request@w3.org; 
public-ws-policy@w3.org; public-ws-policy-request@w3.org
Subject: RE: Are nested assertions part of the policy vocabulary?
 
Hi Maryann:
Perhaps I misunderstood.  Let me rephrase my comments as questions.
 
Since Policy 1 
<Policy>
<ws-addressing>
<Policy/>
</ws-addressing>
</Policy> 
was intended to mean that ALL options ( anonymous, non-anonymous) are 
supported. 
 
And Policy 2
<Policy>
<ws-addressing>
<Policy>
<ws-addressing: Anonymous> 
</Policy>
</ws-addressing>
</Policy> 
was intended to mean that  ONLY anonymous was supported. 
Should Policy 1 match Policy 2 in the intersection algorithm?
All the best, Ashok 

From: public-ws-addressing-request@w3.org 
[mailto:public-ws-addressing-request@w3..org] On Behalf Of Maryann Hondo
Sent: Thursday, April 19, 2007 5:55 AM
To: Ashok Malhotra; Anthony Nadalin
Cc: Ashok Malhotra; public-ws-addressing@w3.org; 
public-ws-addressing-request@w3.org; public-ws-policy@w3.org; 
public-ws-policy-request@w3.org
Subject: RE: Are nested assertions part of the policy vocabulary?
 

Ashok, 
I would like to clarify my comments. 

I was trying to say, that the WS-Addressing group seemed to be trying to 
use nested assertions to indicate a "constraint". 
My understanding of the semantics are the following: 
<Policy>
<ws-addressing>
<Policy/>
</ws-addressing>
</Policy> 
was intended to mean that ALL options ( anonymous, non-anonymous) are 
supported. 

and 
<Policy>
<ws-addressing>
<Policy>
<ws-addressing: Anonymous> 
</Policy>
</ws-addressing>
</Policy> 
was intended to mean that  ONLY anonymous was supported. 

This to me, ths meant that the "intent" of the base assertion was being 
"constrained" by the presence off a nested assertion 
and that was ok if the working group understood the semantics they were 
expressing ( i.e. the "absence" of a nested assertion 
means "no constraints" or "all options are supported") 

 and I thought the language of the ws-policy spec allowed this 
interpretation since  a nested assertion could be seen to be 
qualifying the base assertion with a constraint rather than a capability. 

Authors MAY define that an assertion contains a policy expression (as 
defined in 4. Policy Expression) as one of its [children]. Nested policy 
expression(s) are used by authors to further qualify one or more specific 
aspects of the original assertion. 


The spec already says the following so I don't think alternative 1 really 
adds anything, unless I'm missing something, like Tony, I need more of an 
explanation of what you are suggesting you want the intersection to do: 

Because the set of behaviors indicated by a policy alternative depends on 
the domain-specific semantics of the collected assertions, determining 
whether two policy alternatives are compatible generally involves 
domain-specific processing. 

Maryann 

Anthony Nadalin/Austin/IBM@IBMUS 
Sent by: public-ws-addressing-request@w3.org 
04/19/2007 03:41 AM 


To
"Ashok Malhotra" <ashok.malhotra@oracle.com> 
cc
"public-ws-addressing@w3.org" <public-ws-addressing@w3.org>, 
"public-ws-policy@w3.org" <public-ws-policy@w3.org>, 
public-ws-policy-request@w3.org 
Subject
RE: Are nested assertions part of the policy vocabulary?
 


 
 




#1 " dependent on the semantics of the parent assertion." not sure what 
this would mean can you give some guidance here ?
#2 is real dangerous as you have no idea what you are matching on, one day 
it could be XYZ and another day it could be ABC.

Anthony Nadalin | Work 512.838.0085 | Cell 512.289.4122
"Ashok Malhotra" <ashok.malhotra@oracle.com>

"Ashok Malhotra" <ashok.malhotra@oracle.com> 
Sent by: public-ws-policy-request@w3.org 
04/16/2007 04:23 PM 
 




To

"public-ws-policy@w3.org" <public-ws-policy@w3.org>, 
"public-ws-addressing@w3.org" <public-ws-addressing@w3.org> 


cc



Subject

RE: Are nested assertions part of the policy vocabulary?
 







I?m at the OASIS Symposium and have had extensive discussions with the 
WS-Addressing folks re. the problems they are having in using WS-Policy to 
express their requirements.

As I see it, the sticky usecase is where the provider wants to say this it 
supports WS-Addressing in all its manifestations and the requester 
specifies that it supports a particular variation of WS-Addressing. These 
two policies must match. Thus, the provider says:

<Policy>
<ws-addressing>
<Policy/>
</ws-addressing>
</Policy>

And the requester says:

<Policy>
<ws-addressing>
<Policy>
<ws-addressing-specific-assertions> 
</Policy>
</ws-addressing>
</Policy>

These two policies must match in the intersection algorithm. The text that 
prevents them from matching says:

?If either assertion contains a nested policy expression, the two 
assertions are compatible if they both have a nested policy expression and 
the alternative in the nested policy expression of one is compatible with 
the alternative in the nested policy expression of the other.?

In the note below (which Glen +1ed), Maryann suggests that a Policy with 
just the <ws-addressing> assertion is expressing a constraint which can be 
met in several ways ? at least that?s how I read her note. She does not, 
however, suggest concrete wording. Here are a couple of suggestions: 
1. Change the quoted text above to say that matching of nested policy 
assertions is dependent on the semantics of the parent assertion. This 
way, WS-Addressing could define its own semantics for matching and solving 
their usecase.
2. Bob Freund suggested a wildcard assertion that could be included within 
a nested Policy that would match any other nested policy. 

All the best, Ashok 
 


From: Maryann Hondo [mailto:mhondo@us.ibm.com] 
Sent: Wednesday, April 04, 2007 7:37 AM
To: Glen Daniels
Cc: Ashok Malhotra; Monica J. Martin; public-ws-policy@w3.org; 
public-ws-policy-request@w3.org
Subject: RE: Are nested assertions part of the policy vocabulary?


Glen, 
I think the problem is that the assertions are really trying to express a 
constraint .....and should be something 
like "nonAnonymousONLY". so the absence, is not the absence of support but 
rather the absence of the constraint. 

And in this case I think the " no constraints" is sufficient for your use 
case 
The client has no constraints on what the provider will do. 
That should intersect with all the provider options. 

I hope we can talk this through on the call. 
Maryann 

"Glen Daniels" <gdaniels@progress.com> 
Sent by: public-ws-policy-request@w3.org 
04/04/2007 09:59 AM 
 


To
"Monica J. Martin" <Monica.Martin@Sun.COM>, "Ashok Malhotra" 
<ashok.malhotra@oracle.com> 
cc
<public-ws-policy@w3.org> 
Subject
RE: Are nested assertions part of the policy vocabulary?
 


 
 





Hi Monica:

I'm a little confused here. Are you and MaryAnn indeed saying that
selecting the first alternative in Ashok's (and indeed WS-Addressing's)
example means that neither anonymous nor non-anonymous responses are
allowed? That certainly isn't the goal of the policy, and indeed this
interpretation would seem to disallow ANY kind of response.

How would you write a consumer policy which was meant to successfully
intersect with endpoint policies which either a) express nothing about
anonymous responses, b) express a requirement for anonymous responses,
or c) express a requirement for non-anonymous responses?

--Glen

> -----Original Message-----
> From: public-ws-policy-request@w3.org 
> [mailto:public-ws-policy-request@w3.org] On Behalf Of Monica J. Martin
> Sent: Tuesday, April 03, 2007 5:30 PM
> To: Ashok Malhotra
> Cc: public-ws-policy@w3.org
> Subject: Re: Are nested assertions part of the policy vocabulary?
> 
> 
> 
> hondo: Ashok,
> My response is yes.
> Maryann
> 
> >>mm1: Ashok, agree with MaryAnn on question one answer - this point 
> has been made that the nested assertions are part of the policy 
> vocabulary. Yet, an important point associated with this surrounds 
> whether or not the guiding conformance [1] requires support for those 
> response types - that provides substance on your second 
> question and its 
> disposition.. [2]
> 
> We also state in Section 3.2 Framework before the statement you cite:
> 
> An alternative with zero assertions indicates no behaviors. An
> alternative with one or more assertions indicates 
> behaviors implied
> by those, and only those assertions.
> 
> Remember: (no position just stating the action-result), we augmented 
> this text in 
> http://www.w3.org/Bugs/Public/show_bug.cgi?id=3602 Issue 3602.
> 
> [1] WS-A specification(s) referenced
> [2] Related to empty and the base assumptions of WS-Addressing.
> 
> >Ashok Malhotra wrote: Section 3.2 of Framework says "When an 
> assertion whose type is part of the policy's vocabulary is 
> not included in a policy alternative, the policy alternative 
> without the assertion type indicates that the assertion will 
> not be applied in the context of the attached policy 
> subject." Are nested assertions included in the policy's 
> vocabulary?
> >
> >Consider the following example:
> >
> > <wsp:ExactlyOne>
> > <wsp:All>
> > <wsam:Addressing> <-- supports all response 
> types --> Alternative 1
> > <wsp:Policy> 
> > </wsp:Policy>
> > </wsam:Addressing>
> > </wsp:All>
> > <wsp:All>
> > <wsam:Addressing> <-- requires Anonymous 
> responses --> Alternative 2
> > <wsp:Policy>
> > <AnonymousResponses />
> > </wsp:Policy>
> > </wsam:Addressing>
> > </wsp:All>
> > <wsp:All>
> > <wsam:Addressing> <- requires nonAnonymous 
> responses --> Alternative 3
> > <wsp:Policy>
> > <NonAnonymousResponses />
> > </wsp:Policy>
> > </wsam:Addressing>
> > </wsp:All>
> > </wsp:ExactlyOne>
> ></wsp:Policy>
> >
> >If Alternative 1 is selected, does this mean that neither 
> Anonymous responses nor NonAnonymous responses are allowed as 
> both are part of the policy vocabulary but not included in 
> the alternative.
> >
> >All the best, Ashok
> >
> > 
> >
> 
> 
> 
> 







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Received on Wednesday, 9 May 2007 14:20:21 GMT

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