ZyXEL GS1920 Series User Guide - Page 318

About SNMP

Page 318 highlights

Chapter 38 Access Control 38.7 Technical Reference This section provides technical background information on the topics discussed in this chapter. 38.7.1 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 1 (SNMPv1), SNMP version 2c or SNMP version 3. The next figure illustrates an SNMP management operation. SNMP is only available if TCP/IP is configured. Figure 234 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 (the 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 number of packets received, node port status and so on. 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 160 SNMP Commands LABEL 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 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. Trap Used by the agent to inform the manager of some events. GS1920 Series User's Guide 318

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Chapter 38 Access Control
GS1920 Series User’s Guide
318
38.7
Technical Reference
This section provides technical background information on the topics discussed in this chapter.
38.7.1
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 1 (SNMPv1), SNMP version 2c or
SNMP version 3. The next figure illustrates an SNMP management operation. SNMP is only available
if TCP/IP is configured.
Figure 234
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 (the 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 number of packets
received, node port status and so on. 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 160
SNMP Commands
LABEL
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 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.
Trap
Used by the agent to inform the manager of some events.