P3P Future Work Items 4.a: Compact Policies Performance Issues

P3P Future Work Items 4.a: Compact Policies Performance Issues

Purpose

The abbreviated syntax of Compact Policies, CPs, and the delivery system via
the HTTP P3P header stems from the belief that Full (XML) Policies cannot be
presented at cookie set time.  This belief is held because Set-Cookie
headers are received and acted upon in the initial response to an HTTP
delivered asset.  It is upheld that discovery of a Full Policy prior to
acceptance of a cookie would be difficult/resource intensive for a User
Agent, UA.   

This lack of Full XML Policy, and the extensibility therein however creates
numerous issues particularly with regard to accuracy.


Scope:

Possible areas of exploration could include:

	1.	Empirical study of effect on UA performance with real time
discovery of Full Policy through PRF of cookie policies
	2.	Possibility of "cached" Set-Cookie's Statements pending
subsequent resolution on related Full Policies.
	3.	Pre-fetching and storing Cookie Policies within allowed
expiry for given hosts. 


Resources:

As this is entirely a User Agent issue, resources for this project would
likely need to come from UA developers with input from all members of a
future working group.

Time Frame:

These issues are difficult to resolve and are highly dependent on user
experience - which it self highly dependent on issues such as average user
bandwidth, internet latency and connectivity.  The need to resolve this
issue may be hastened by the legal interpretations of the inherent inability
for CPs to be sufficiently nuanced.





Brooks Dobbs
Director of Privacy Technology
DoubleClick, Inc.

office: 404.836.0525
fax: 404.836.0521
email: bdobbs@doubleclick.net

Received on Friday, 20 December 2002 13:54:13 UTC