Cisco 11503 Administration Guide - Page 187

Chapter 5 Configuring Simple Network Management Protocol (SNMP) Management Information Base (MIB) Overview Management Information Base (MIB) Overview SNMP obtains information from the network through a Management Information Base (MIB). The MIB is a database of code blocks called MIB objects. Each MIB object controls one specific function, such as counting how many bytes are transmitted through an agent's port. The MIB object comprises MIB variables, which define the MIB object name, description, default value, and so forth. The collection of MIB objects is structured hierarchically. The MIB hierarchy is referred to as the MIB tree. The MIB tree is defined by the International Standards Organization (ISO). The MIB is installed on the SNMP manager and is present within each agent in the SNMP network. At the top of the tree is the broadest information about a network. Each branch and sub-branch of the tree gets progressively more specific, and the lowest branches of the tree contain the most specific MIB objects; the leaves contain the actual data. Figure 5-2 shows an example of how the MIB tree objects become more specific as the tree expands. Note There are two versions of the MIB tree as defined by ISO: MIB-I and MIB-II. MIB-II has more variables than MIB-I. Refer to the MIB-II standard in RFC 1213, "Management Information Base for Network Management of TCP/IP-based Internets: MIB-II." OL-5647-02 Cisco Content Services Switch Administration Guide 5-5