SNMP - NETWORK MANAGEMENT CONCEPTS
Network Management Architecture:
The model of network management that is used for TCP / IP network management includes the following key elements.
• Management Station
• Management Agent
• Management Information Base
• Network Management protocol
Management Station: It is a stand alone device but it may be a capability implemented on a shared platform. IN either case Management Station serves as the interface for the hu8man network manager into the network management system. At a minimum the station will consists of the following:
• A set of management application for data analysis, fault recovery and so on.
• An interface by which the network manager my monitor and control the network.
• The capability of translating the network manager‘s requirenment into the actual monitoring
and control of remote elements in the network
• A database of information extracted from the MIB of all the managed entities in the network.
Management Agent: This is other active element. Platforms like bridges, hosts, routers and hubs may be equipped with SNMP agents so that they may be managed from the management stations. The management agent responds to request for information and actions from the management stations and may asynchronously provide the management stations with important but unsolicited information.
Management Information Base :
Resources in the network may be managed by representing those resources as objects. Each objects is essentially a data variable that represents one aspects of management agent. The collection of object is referred to as a Management Information Base (MIB) The MIB functions as a collection of access points at the agent for the management station. These objects are standardized across system of a particular class (common set of objects is used for the management of various bridges). A management station performs the monitoring functions by retrieving the value of MIB objects. An Management station can cause an action to take place at an agent or can change the configuration setting at an agent by modifying the value of specific variables.
Network Management Protocol :
The management stations and agents are linked by Network Management Protocol. The protocol used for the management of TCP / IP networks is SNMP, which includes the following key capabilities:
get : enables the management station to retrieve the value of the objects at the agent. set : Enables the management station to set the4 value of objects at the agent.
trap: enables an agent to notify the management station of significant events.
It is prudent to have two system to perform Management station functions to provide redundancy.
Network Management Protocol Architecture:
SNMP was designed to be an application level protocol that is part of TCP / IP protocol suite. It operates over UDP. Following figure shows the typical configuration of SNMP Protocol: