To automate the process of Service Level Specification negotiation, admission control and configuration of network devices correctly to support the provisioned QoS, each DiffServ network may be added with a new component called a Bandwidth Broker (BB). The bandwidth broker is a complex entity that might need integration of several technologies such as standard interface for inter/intra domain communication, protocol entity for communication, standard protocol and database. It would be sensible to implement the bandwidth broker that can make use of ease of programming, robustness, extensibility, object-orientation and simple definition of interface. This paper describes a bandwidth broker implementation in Java that is capable of managing and provisioning resources of a Diffserv domain. Both COPS and COPS-PR are implemented using Java language. Diffserv kernel package for Linux is extended to support bandwidth broker functionality. The source code of our implementation is publicly available to enable QoS researcher in building their prototype. RAP working group is developing a policy based management framework. A Policy Enforcement Point (PEP) is usually a router that handles IP traffic, implementing policy-based admission control. The Policy Deicision Point (PDP) has a view over the whole network area through its PEPs, decides whether or not to admit a specific data flow. The purpose of the Common Open Policy Service (COPS) protocol is to exchange policy information between a PDP and its clients PEPs (RFC 2748). COPS supports two models, outsourcing and policy provisioning (RFC3084). The policy provisioning model is supported in DiffServ architecture where user contacts the PDP. However outsourcing model, in which the user approaches the PEP for instance the router, which in its turn contacts the PDP is supported by IntServ/RSVP architecture.
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