Short for Simple Network Management Protocol, SNMP was first introduced in 1988 and is a query, command, and response protocol. SNMP examines and changes configuration parameters of LAN and WAN connected repeaters, bridges, routers, switches, and other devices connected to a network.
SNMP is currently available in three versions:
- SNMP version 1 (SNMPv1): SNMP v1 is the first implementation of SNMP and is described in RFC 1157. SNMP v1 operates in the specifications of SMI and has support for such protocols as CLNS, DDP, IP, IPX, and UDP.
- SNMP version 2 (SNMPv2): SNMP v2, more appropriately known as SNMP v2c (as in RFC 1901), was introduced in RFC 1441 and has improved support increasing efficiency and error handling.
- SNMP version 3 (SNMPv3): SNMP v3 was introduced in RFC 3410 and improves in security and privacy.
SNMP defaults to use port 161.