SNMP

Definition

simple Network Management Protocol; A management protocol , part of the TCP/IP protocol suite, that allows the monitoring and management of network and peripheral computer equipment by sending and receiving packets via UDP port 161 and 162.

See also

Wikipedia article: http://en.wikipedia.org/wiki/Simple_Network_Management_Protocol
Microsoft TechNet article "What is SNMP?": http://technet.microsoft.com/en-us/library/cc776379(v=ws.10).aspx