ZyXEL Communications 4728F User Manual

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Chapter 46 Access Control
XGS-4526/4528F/4728F User’s Guide
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46.3  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), 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 217   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.