The Structure of Management Information, version 2 (SMIv2) is a component for network management. Its functions are

1. To name objects
2. To define the type of data that can be stored in an object
3. To show how to encode data for transmission over the network

Name

• SMI requires that each managed object (such as a router, a variable in a router, a value)have a unique name. To name objects globally, SMI uses an object identifier, which is a hierarchical identifier based on a tree structure

Type

• The second attribute of an object is the type of data stored in it. To define the data type,SMI uses fundamental Abstract Syntax Notation 1 (ASN.l) definitions and addssome new definitions.

• In other words, SMI is both a subset and a superset of ASN.1.SMI has two broad categories of data type: simple and structured. We first definethe simple types and then show how the structured types can be constructed from thesimple ones

Encoding Method

• SMI uses another standard, Basic Encoding Rules (BER), to encode data to be transmitted over the network. BER specifies that each piece of data be encoded in triplet format: tag, length, and value, as illustrated in Figure