| The complexity, heterogeneity and distributed architecture of the present network has considerably add difficulties to network management. Policy Based Network Management , being a new developing research and subject in the field of network management , can efficiently simplify the network management process. It separates control of the administration behavior from concrete execution ,so the administrator need not to configure all the network devices one by one, but just establish some meaningful management policies and the system will carry out the management of network resources automatically according to policy. Being the abstract of management intelligence and independent of the concrete devices, Management policy can guarantee the dependability and consistency of management. IETF policy management frame includes policy management tool(PMT),policy repository(PR),policy decision point (PDP) and policy enforcement point (PEP). PMT offers the GUI to network administrator for input, modification or deletion of policy and relevant information. PR is used to store policy and relevant information. PDP know the state of the network devices and can configure and rectify the policies in the devices. It can also receive the requests from PEP and make policy decisions. PEP is the component that enforce policy on network devices. To manage through policies ,consequent network devices have to be configured with policy information by PEP. As to QoS management , PBNM can make corresponding policy according to SLA, control the treatment of user application demands and offer certain quality of service guarantees. It can manage network resources effectively and reasonably according to different level o or demand of user. It can not only guarantee high using efficiency of networks, but also offer different ranks of quality of service to different users.There are mainly two kinds of modes in QoS policy management: outsourcing mode and providing mode. Outsourcing mode is used when PEP request an instant policy decision , under this mode, network event and policy request and decision take place at the same moment, their communication protocol being COPS-RSVP. While under providing mode , the network administrator defines the policy that is correlated with the devices in advance, and download it to PEP. The network event and policy request do not take place at the same time as under outsourcing mode ,namely PDP responds to outside events ,PEP events and their combination in advance (the relationship of N:M) unlike that of the relationship of 1:1 of PEP event and PDP decision under outsourcing mode. Its communication protocol is COPS-PR.On the basis of studying the policy-based system frame presented by IETF and analyzing the end to end IP QoS ,we designed the end to end QoS policy management environment that appy the policy-based idea to the end to end QoS management. Through analysis of how the RSVP(Resource Reservation) message pass through DiffServ network under policy control ,the End to end QoS working process based on policy management ideology with IntServ being the access network and DiffServ being the backbone is illustrated .Hereby, the idea of applying the combination of outsource mode and providing mode to solving the policy decision-making ,distribution and configuration and relevant problems during the management process. The unitary system architecture is also given which includes mainly five parts: policy management tool, directory server store module, PDP module, COPS communication module and PEP module.This paper further analyze and study the monitoring component and PEP module in this architecture and define the corresponding solutions.Policy based QoS management system should be a flexible one. To assure the performance of the network, it must make policy decision according to the present network state and update policy as soon as the state of the network changes.To realize the flexible application of the policy, it is necessary to offer monitoring for the state of the network. With...
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