System information

SNMP Overview

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MIBs

A Management Information Base (MIB) is a formal description of a set of network objects

that can be managed using the Simple Network Management Protocol (SNMP).

The unit of data collected is called the SNMP object. For each device, a set of SNMP

objects and rules for addressing the objects are defined in a MIB file. MIBs are key to the

logical, orderly functioning of SNMP. MIB objects (OIDs) are represented by a tree

hierarchy; each object has a unique address based on its position in the tree. The address

count begins from the “root” of the object tree; one number is added to the address with

each new branch. The root of the tree is unnamed and splits into three main branches:

Consultative Committee for International Telegraph and Telephone (CCITT),

International Organization for Standardization (ISO), and joint ISO/CCITT.

These branches and those that fall below each category have short text strings and integers

to identify them. Text strings describe object names, while integers allow computer

software to create compact, encoded representations of the names.

The object identifier in the Internet MIB hierarchy is the sequence of numeric labels on

the nodes along a path from the root to the object. The Internet standard MIB is

represented by the object identifier 1.3.6.1.2.1. It also can be expressed as

iso.org.dod.internet.mgmt.mib. The format of the MIB is defined as part of the SNMP.

ISO

(1)

ORG

(3)

DOD

(6)

Internet

(1)

Typical beginning of an

object identifier

1.3.6.1