Extensible Snmp Agent

With the rapid development of Internet and the urgent requirement for network management,Internet Engineering Task Force (IETF) proposed the Simple Network Management Protocol (SNMP). SNMP contains a series of protocols and criterions that provide methods for the management system and network devices to exchange management information,as well as the status information and error reports. In the network management architecture based on SNMP,agents play an important role,because they are the source of management information and they take the responsibility to deal with SNMP protocol and support the Management Information Base (MIB).At the beginning of this article,the author introduce the history of network management technologies and discuss some important concepts in network management models,including the Structure of Management Information (SMI),the Management Information Base and the Simple Network Management Protocol.According to the urgent need to dynamically extend agents,methods about the implementation of extensible agent,including the method to deal with protocols,build the MIB frames and apply security models,are introduced in this article. The agent software introduced in this article is compatible for various SNMP versions. Using component models,the agent can extend the MIB modules and meet the requirement of new implements. Then the design and implement of a system that monitor the Internet content viewed by computer users are introduced. This implement verifies the usability and efficency of the extensible agent.At last the technologies that may be used to reform the extensibility agent and monitoring system are introduced in brief.