| In recent years, with the rapid development of Internet, and especially the strong impulse of the relevant technology such as IPv6, Next Generation Network and the 3rd Generation Mobile Communication, it makes that the present network has manifested characteristics, which has numerous business and kinds of equipment, and is difficult to manage uniformly. Traditional network management based on SNMP(Simple Network Management Protocol)has exposed obvious weaknesses. It regards equipment as the centre, manages statically, and requires network administrators to know well the interface and names of various kinds of equipment, which is difficult to reach the objectives of flexibility and efficiency.Policy Based Network Management , being a new developing research and subject in the field of network management , can efficiently simplify the network management process. Policy is a set of rules to manage, configure and control the access to network resources. PBNM system 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 apply the policy-based idea to the end to end QoS management. 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. Taking two representative QoS policies as example, the paper combines PBNM and QoS, discusses the basic principle of policy information model and the mapping to the directory server, and extends it. It takes Netscape Directory Server as policy repository, designs and realizes the policy management tools.A g...
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