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Ordering between assertions

From: ashok malhotra <ashok.malhotra@oracle.com>
Date: Mon, 13 Aug 2007 15:39:12 -0700
Message-ID: <46C0DD90.6010906@oracle.com>
To: public-ws-policy@w3.org
CC: Anish Karmarkar <Anish.Karmarkar@oracle.com>

Consider a policy that includes Reliable Messaging, Header Encryption 
and Signing.
It seems clear that the Reliable Messaging headers should be added 
first, the headers encrypted next that finally the signature created and 
affixed.  At the receiving end, the signature should be checked first, 
the headers decrypted next and finally the Reliable Messaging headers 
processed.  This implies that the Policy assertions be processed in a 
definite sequence.

The framework document says:
"Assertions within an alternative are not ordered, and thus aspects such 
as the order in which behaviors (indicated by assertions) are applied to 
a subject 
<http://www.w3.org/TR/2007/PR-ws-policy-20070706/#policy_subject> are 
beyond the scope of this specification. However, authors can write 
assertions that control the order in which behaviors are applied."

It seems to me that this is a fairly common scenario and it may be good 
to show an example, in the Guidelines document,.of how such an ordering 
assertion may be authored.
-- 
All the best, Ashok
Received on Monday, 13 August 2007 22:39:47 GMT

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