SNMP, which stands for Simple Network Monitoring Protocol, is an internet management protocol, by which communications devices are monitored and controlled by network management systems. It provides a protocol for sending and receiving management information that a management program can use as a basis for its functionality across the internet.
SNMP performs operations by manipulating the Management Information Base (MIB), which is a database of information about managed objects. All management-relevant data can be defined in object-oriented terms as a set of object, relations, and operations onto and between objects. The MIB is a collection of these objects.
All the managed objects are organized in a hierarchical structure called the 'Management Tree'. Each branch in the SNMP tree is assigned a specific number. When you concatenate all of the numbers of the branches leading to a particular object in the tree together, the decimal notation, known as the Object Identifier, represents a unique path in the tree. Each object defined in the MIB has a unique Object Identifier associated with it.
Only four operations are available to the protocol:
It is through the sending, receiving, and logging of many of these simple transactions that network management systems using SNMP accomplish their tasks.