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Chapter 13 System Configuration
NetAtlas EPON Manager User’s Guide
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network via SNMP version 2c. The next figure illustrates an SNMP management
operation. SNMP is only available if TCP/IP is configured.
Figure 104 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
(your OLT). 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.
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:
Table 74 SNMP Commands
COMMAN
D
DESCRIPTION
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 SNMP, 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.