simple network management protocol (SNMP)
The Simple Network Management Protocol (SNMP) allows centralized network management for many network components. The primary goals of the SNMP protocol are to reduce the complexity of the management functions, to make the protocol extensible, and to make it independent of any network components.
There are three management areas where this protocol can be used:
- Monitoring allows events to be recorded and network statistics to be collected.
- Controlling supports changing device parameters and variables.
- During administration, information is recorded that describes the development of the network setup.
The architecture model of SNMParchitecture model of SNMP is very simple. According to this model, a network is divided into the network management stations, the Network Management Stations( NMS), and the network components, the Network Management Agents( NMA). The NMS stations run applications to monitor and control the NM agents. The network components router, host, bridge or terminal server have network management agents that perform the management functions. Using SNMP, communication takes place between the management station (NMS) and the network components (NMA). This communication includes the transfer of relevant management data collected by the network components and stored in the MIB and transferred to the management station, as well as the control data for the network components.
Examples of such information are network addresses, physical addresses, timers, counters and protocol parameters. The agent responds to SNMP requests from the manager by querying or setting MIB values. The latter has the effect of controlling the network node. In addition, the agent can send a so-called trap message on its own due to certain events.
SNMP uses Abstract SyntaxNotation One( ASN.1) as presentation language. Thanks to the flexibility of ASN.1, network objects can be added to the Management Information Base (MIB) as needed. A SNMP version with extended properties and definitions is the successor protocol SNMPv2.
The basic document on SNMP are in RFCs 1157, 1441 and 3410.