GE 82-POE Benutzerhandbuch

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Chapter 4: Web-Based Management 
44 
GE-DS-82 and 82-PoE Ethernet Managed Switch User Manual 
An SNMP-managed network consists of four key components: Network management 
stations (NMSs), SNMP agents, Management information base (MIB) and Network-
management protocol: 
•  Network management stations (NMSs):  Sometimes called consoles, these 
devices execute management applications that monitor and control network 
elements. Physically, NMSs are usually engineering workstation-caliber computers 
with fast CPUs, megapixel color displays, substantial memory, and abundant disk 
space. At least one NMS must be present in each managed environment. 
•  Agents:  Agents are software modules that reside in network elements. They 
collect and store management information such as the number of error packets 
received by a network element. 
•  Management information base (MIB):  A MIB is a collection of managed objects 
residing in a virtual information store. Collections of related managed objects are 
defined in specific MIB modules. 
•  Network-management protocol:  A management protocol is used to convey 
management information between agents and NMSs. SNMP is the Internet 
community's de facto standard management protocol. 
SNMP Overview 
SNMP itself is a simple request/response protocol. NMSs can send multiple requests 
without receiving a response. 
•  Get - Allows the NMS to retrieve an object instance from the agent. 
•  Set - Allows the NMS to set values for object instances within an agent. 
•  Trap - Used by the agent to asynchronously inform the NMS of some event. The 
SNMPv2 trap message is designed to replace the SNMPv1 trap message. 
SNMP Community 
An SNMP community is the group that devices and management stations running 
SNMP belong to. It helps define where information is sent. The community name is 
used to identify the group. A SNMP device or agent may belong to more than one 
SNMP community. It will not respond to requests from management stations that do 
not belong to one of its communities. SNMP default communities are:  
•  Write = private  
•  Read = public 
System Options 
Use this page to define management stations. You can also define a name, location, 
and contact person for the Managed Switch.