Erik Liden and Anders Torger wrote a master's thesis in January 2000 on the "Implementation and Evaluation of the Common Open Policy Service (COPS) Protocol and its use for Policy Provisioning" that you might want to review.
They did their master's work at the Department of Computer Science and Electrical Engineering of the Lulea University of Technology.
> -----Original Message-----
> From: Marco De Bernardi [mailto:firstname.lastname@example.org]
> Sent: Monday, February 18, 2002 7:54 AM
> To: 'email@example.com'
> Subject: COPS, COPS-PR performance and scalability
> Hi to everybody,
> I'm interested to evaluate COPS/COPS-PR performance and
> scalability. Do any
> studies already exist? Where can I find them?