A policy based QoS management system for the IntServ/DiffServ based Internet

This paper reports the design, implementation, and performance evaluation of a policy based QoS management system for the IntServ/DiffServ based Internet which is based on COPS for interfacing with the network device and on LDAP for interfacing with a directory for storing policies. The design is based on distributed components and CORBA is used as a middleware for component interaction. The Diffserv policies are installed based on the role combination assigned to the network device interfaces and policy caching is used to improve the performance. The feasibility and performance of managing and deploying IntServ and Diffserv, policies for QoS management is demonstrated using Linux-based routers. The preliminary performance measurements show that the policy server response time is below 5 ms per request for 20 COPS-RSVP requests per second. COPS-PR processing takes more time compared to COPS-RSVP requests. It is found that the directory access could become a bottleneck in scaling the performance of the policy server and it can be improved substantially by employing appropriate policy caching mechanisms.