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3 about snmp, Figure 124 access control, Figure 125 snmp management model – ZyXEL Communications ZyXEL Dimension GS-4012F User Manual

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GS-4012F/4024 User’s Guide

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Chapter 33 Access Control

Figure 124 Access Control

33.3 About SNMP

Simple Network Management Protocol (SNMP) is an application layer protocol used to
manage and monitor TCP/IP-based devices. SNMP is used to exchange management
information between the network management system (NMS) and a network element (NE). A
manager station can manage and monitor the switch through the network via SNMP version
one (SNMPv1) and/or SNMP version 2c. The next figure illustrates an SNMP management
operation. SNMP is only available if TCP/IP is configured.

Figure 125 SNMP Management Model

An SNMP managed network consists of two main components: agents and a manager.

An agent is a management software module that resides in a managed switch (this switch). An
agent translates the local management information from the managed switch into a form
compatible with SNMP. The manager is the console through which network administrators
perform network management functions. It executes applications that control and monitor
managed devices.

The managed devices contain object variables/managed objects that define each piece of
information to be collected about a switch. Examples of variables include such as number of
packets received, node port status etc. A Management Information Base (MIB) is a collection
of managed objects. SNMP allows a manager and agents to communicate for the purpose of
accessing these objects.