common open policy service (COPS)

The COPS framework, Common Open Policy Service (COPS), is a method to automatically distribute configuration rules to a large number of devices. COPS was originally developed to provide for the distribution and monitoring of admission rules in the Resource Reservation Protocol( RSVP). This approach, which has been extended by the Internet Engineering Task Force( IETF) to include other components, is characterized by its universality.

COPS is a simple request/ response protocol built on top of TCP/ IP that acts between the policy server, the policy decision point( PDP) and the COPS client. It defines three basic elements that make up a policy transaction system: The Policy Enforcement Point( PEP), referred to as the COPS client, enforces the rules on the network and supports different clients in which Differentiated Services( DiffServ) or IPsec may also be implemented. The Policy Decision Point (PDP) sets the central rules while supporting different COPS client types, and the COPS protocol itself conveys the policies.

COPS has the advantage of constantly coordinating between the policy server and the COPS client and can respond to Resource Reservation Protocol (RSVP) requests, for example, by providing more bandwidth to a switch, constantly monitoring status, and responding to other important sessions.