Alcatel-Lucent OmniAccess 700, Cli Configuration Manual

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SNMP (Simple Network Management Protocol)
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Alcatel-Lucent
Beta Beta
CLI Configuration Guide
SNMP A
GENT AND
M
ANAGER
Major components of SNMP that form an integral part of its foundation are the
network device, and the agent and the manager. Let us look at each of these
components individually. A network device or the managed object is a part of the
network that requires some form of monitoring and management.
Agent is a mediator between the manager and the device. The agent is a
program that resides in the device and not a separate entity. It collects
management information from the device and makes it available to the manager.
The agent implements the SNMP protocol which helps in retrieving management
information as defined in the MIBs (Management Information Base) supported on
the device. The agent signals an event to the manager through traps.
A Manager is a management system, which is a separate entity that manages the
devices from a remote place through agents installed on the devices. This
application runs on a computer that is used to manage one or more network
management systems.
Consider an organization having its branches in different geographical locations.
Administration of all the computers present in different localities would be difficult.
When the System Administrator’s computer is installed with the manager and all
other systems and devices across all the offices are installed with the agent,
management becomes easier. The administrator has to just query the agent
through its manager to know the functioning of a specific device. The manager will
implement the network management system, implement SNMP protocol, query
agents, get responses from agents, set variables in agents, and receive
asynchronous events from agents.
The communication between the manager and the agent in a network happens by
means of PDU (Protocol Data Units). The PDUs allow the manager to interact with
the agent in the device. The extent of management depends on the data available
to the manager from the agent, which in turn depends on the support of MIBs on
the agent.
PDUs are encapsulated in the UDP (User Datagram Protocol) for transportation
across the network. UDP is a connectionless transport protocol included in the
TCP/IP suite and described in RFC.