"Web Friendly" Policy Ids

[Hal Lockhart <hal.lockhart@oracle.com>]

Paul,

On the last call you made a remark about making XACML more web friendly by allowing policies to be retrieved by dereferencing their Policy ID which would be an HTTP URI.

(If I have this wrong, please correct me.)

I would like to make two observations about this. First, it has generally found to be operationally inconvenient to put the fully qualified name of any file inside the file. There are many reasons which it may be desirable to change the location of a file, but undesirable to modify the file contents. XML Schema, for example, recognizes this by defining the value of xsi:schemaLocation as merely a hint as to where the schema may be found.

My second comment is that I did look at what 3.0 (and 2.0) says about Policy Id. Policy ID (and Policy Set ID) are required and defined as type anyURI. The values are required to be unique within any PDP and it specifically says that: If the policy identifier is in the form of a URL, then it MAY be resolvable.

It seems to me that this allows you to do what you want to using the current spec, while others are free to use a different scheme.

Hal