SNMP version 1 (SNMPv1) (Original version)
SNMP version 2 (SNMPv2) (Additional Protocol Enhancements)
SNMP version 3 (SNMPv3) (Additional Security Enhancements)
SNMP has become the de-facto standard for network monitoring and management operations and is always being added to and improved. It is a simple agentt/manager protocol whereby agents are managed from a central point in the network by a management device. The devices in the network are configured with agent software and a MIB (Management Information Base) is used to determine which objects on an agent are to be managed. The objects can be protocol operations or physical attributes of the agent device.
In terms of the TCP/IP protocol suite, SNMP is described as an application layer protocol which allows network administrators and engineers to manage performance issues in the network and identify and solve network faults.
There are 3 main components in an SNMP network:
Agent – This is software that runs on a physical devices such as a Router, Switch, Printer or Workstation. The agent updates a local database with information about the current state of the device. The agent will be configured with the IP Address of the Network Management System hosting the manager software.
Manager – An application program that is in communication with agents and is used to query agents about aspects of its database, or even configure additional elements.
MIB – Management Information Base which describes a group of configurable objects within a device.
Everything is controlled from one or more Network Management Systems residing on the network that contain the manager software. The NMS will often give visual and sometimes audible alarms when something critical changes on a device. This will normally be in response to an SNMP agent sending what is known as a TRAP message back to the Network Management System.
Look out for SNMP Part 2 which will describe the operation of SNMP in more detail.
SNMP is covered as part of a number of training courses within the NSTUK Course Portfolio including TCP/IP – A Practical Foundation