Snmp - ZyXEL Communications NWA Seres User Manual

17.9 SNMP

Simple Network Management Protocol is a protocol used for exchanging management information
between network devices. Your Zyxel Device supports SNMP agent functionality, which allows a
manager station to manage and monitor the Zyxel Device through the network. The Zyxel Device
supports SNMP version one (SNMPv1), version two (SNMPv2c), and version three (SNMPv3). The next
figure illustrates an SNMP management operation.
Figure 119 SNMP Management Model
An SNMP managed network consists of two main types of component: agents and a manager.
An agent is a management software module that resides in a managed device (the Zyxel Device). An
agent translates the local management information from the managed device 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 device. 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.
SNMP itself is a simple request/response protocol based on the manager/agent model. The manager
issues a request and the agent returns responses using the following protocol operations:
• Get - Allows the manager to retrieve an object variable from the agent.
• GetNext - Allows the manager to retrieve the next object variable from a table or list within an agent.
In SNMPv1, when a manager wants to retrieve all elements of a table from an agent, it initiates a Get
operation, followed by a series of GetNext operations.
• Set - Allows the manager to set values for object variables within an agent.
Chapter 17 System
NWA/WAC/WAX Series User's Guide
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