US Patent 7321556 Application prioritization policy engine

A system and method for enforcing policies on data packets in a computer network is disclosed. The enforcement of policies is done by prioritizing and regulating the flow of data packets. The regulation of prioritized data packets includes a determination of: service level agreement violations, flow control of data packets of a predefined priority and session resettings. For determination of service level agreements the policy engine carries out a response time calculation and finds if it is in consonance with the response time agreed upon in the service level agreement. Flow control in case of a service level agreement violation is implemented either by reducing the server side window size or by delaying acknowledgement packets sent by the client.