SNMP is short for Simple Network Management Protocol. This protocol provides functionality for controlling and monitoring networks. Trigger by defined events, e.g. errors, the protocol will inform the administrator in an appropriate way.
To use SNMP an additional software is necessary. Here you can set up the parameters for agent and traps only.
All devices monitored have to have an agent. These agents will send in regular intervals, on request or triggered by events data. The structure of this data is defined in MIBs.
The SNMP community provides a simple access protection by creating a community named public with the "ReadOnly" right. A second community, named admin posses the "ReadWrite" right, i.e. members of this community can edit the settings.
Via the community string a SNMP manager discloses his affiliation to a certain community. Unfortunately this string is transmitted as plaintext, making the security vulnerable.
A trap is send each time an event happens.
The message consists among other things of the common TrapID. 7 common TrapIDs are defined: