1. 基于TCP/IP的网络管理包含3个部分：1） MIB， specifies what variables the network elements maintain (the information that can be queried and set by the manager).包含所有代理进程的所有可以查询和修改的参数2） SMI， A set of common structures and an identification scheme used to reference the variables in the MIB3） SNMP，The protocol between the manager and the element, called the Simple Network Management Protocol (SNMP).2. SNMP5 messages1) get-request2) get-next-request3) set-request4) get-response5) trapThe first three messages are sent from the manager to the agent, and the last two are from the agent to the manager.The manager sends its three requests to UDP port 161. The agent sends traps to UDP port 162. using ASN1 and BER encoding rule.3. Object IdentifierAn object identifier is a data type specifying an authoritatively named object. An object identifier is a sequence of integers separated by decimal points.All variables in the MIB start with the object identifier 1.3.6.1.2.1Case Diagrams visually illustrate the relationships between the various MIB variables in a given group.4. Instance Identification1) Simple variables are referenced by appending ".0" to the variable's object identifier.2) TablesAll the entries in MIB tables are lexicographically ordered by their object identifiers. tables are accessed in a column-row order.5. 应用举例1） 接口MTU2） 路由表