9032947 SNMP Management 65
5. SNMP MANAGEMENT

The SNMP Protocol

SNMP (Simple Network Management Protocol) is a communication
protocol designed specifically for the purpose of managing devices or
other elements on a network. Network equipment commonly managed
with SNMP includes hubs, switches, route rs, a nd ho st compu ters . SNMP
is typically used to configure these types of devices for proper operation
in their network environment, as well as to monitor them to evaluate their
performance and detect potential problems.
Managed entities supporting SNMP typic ally contain s oftware, whic h runs
locally on the device and is referred to as an ag ent. In Figure 5- 1, software
in an ELS100-24TXG switch functions as an agent, monitoring and
controlling the func tionality of the sw itch.
Figure 5-1. ELS100-24TXG Switches Managed by an
SNMP Management Workstation
A defined set of variables, referred to as managed objects, is m aintained
by the agent and used to manage the device. These objects are defined
in a Management Information Base (MIB) which allows for a standard
presentation of the information controlled by the agent over the network.
The software used to access the information maintained by the SNMP
agents across a network is referred to as the SNMP Manager, and
typically runs on a workstation.
The SNMP manager software uses a MIB spec ification , equiv alent to that
which the agent maintains, to read and write objects controlled by the
agent for purposes of configuring and mo ni toring the device. S NMP
defines the format of the MIB specifications and the protocol used to
access this information.