| With the constant enlargement of the network scale, the network has already become the important pillars and basic platforms of different applications and information services. Network management is a series of supervising , maintaining and managing operations which could guarantee the network service safe, reliable and high-efficient. Network management is the key of whether the network could play its important role or not.At present, the standard of network management is the simple network management protocol made by IETF. IETF made SNMPvl in 1993, and then carried out improvement edition SNMPv2. In 1999, they issued SNMPv3 edition formally, which increased authentication and data secret function to SNMPvl and SNMPv2. SNMPv3 cleared away the potential safety hazard on the large scale of application of SNMP.Systems following SNMP include two parts: Agent and Manager. All managed equipments, including router, network bridge, server and workstation, should contain Agent module. Agent module is responsible for:1. Collecting and maintaining local information.2. Sending message to Manager, when receiving Manager's request; or sending trap to Manager when abnormity taking place.3. Changing configuration information or operating parameters according to Manager's requirement.4. Maintaining a MIB closely related to the equipment. Manager module achieves functions of network supervising,network management and network configuration through communicating with Agent module. It offers method of inquire and modify status of equipment, method of inquire and modify configuration information of equipment. In a word, it should support SNMP standard operations--GET, GETNEXT, GETBULK, SET, TRAP, WALK, at the same time it should provide user interface, such as GUI.Network management workstation (manager) connects to managed equipments(trap) via network. The agent modular in the equipment maintains state and current configuration information of the equipment, responds to the management workstation's request, triggerthe trap when specific events happen.At present many companies have developed their self-owned intellectual property network management systems based on SNMP. These systems all worked in IPv4 environments. With the coming into use of next generation IP technology -IPv6, these systems have to face the problem of upgrading to IPv6. There is still no mature SNMP software packets supporting IPv6 nowadays. So it is of great value to develop such a system which support IPv6.Developing a set of SNMPv3 APIs in IPv6 environment is the prerequisite of developing any other applications. So the first task of the project is to design a set of simple but practical SNMPv3 APIs, which should support the security feature of SNMPv3 (including user authentication and data encryption transfer) and support IPv6 at the same time. In fact, SNMP does not state the network environment required, here the supporting for IPv6 means two aspects: (l)SNMP packets can be transferred in IPv6 network ;(2)Applications built on such API can work on IPv6 hosts or equipments. These APIs should be simple, high efficient and easily transplanted. Any management function should based on these APIs.To simplify the design of SNMPv3 API, we can modify and extend existing software packets to satisfy the requirement. We use UCD-SNMP4.01 in this project. The main tasks including, (1) modifying UCD-SNMP software packets to fully support IPv4 and IPv6, (2) supplementing security mechanism that not included in UCD-SNMP software packets, (3) selecting proper technology to make the modification could be accepted and easily understood.This design is based on the existed SNMP packet. Through adding new module to original source program, we can make it support IPv6. The main modification including:(1) Adding module in agent to support IPv6 MIB;(2) Modifying data structure of IP address in the original packets to support IPv6;(3) Modifying functions that are not compatible with IPv6 in IPv4 packets;(4) Using basic APIs to build other parts of ne...
|
PDF Full Text Request