An SNMP simulator fools the network management application software into believing it is talking via the SNMP protocol to one or more devices, just like a flight simulator allows a pilot to believe they are flying a plane.
SNMP Simulators are used for development, testing, and training of network management system software.
Features in this area vary widely, from the no-cost to commercial offerings.
The better simulators will allow creation of any type of dynamic scenario, both in terms of MIB object behavior as well as trap generation.
Since current network management standards comprise a set of protocols, the better simulators integrate the current network management standards, such as NetFlow, command-line interfaces (CLI), etc.