MIMIC solves a classical simulation problem: network management software typically manages large networks. Traditionally, in order to setup such networks for the purposes of software development, software testing or training, physical equipment had to be separately purchased and assembled in laboratories. To reduce the expense, most of the network can be simulated.
The principle behind SNMP simulation is that the SNMP protocol is an interface that can be simulated. SNMP requests carry data values for MIB objects, which can be shaped at will by the simulator, thus representing any device which has an SNMP interface. In contrast to Network simulation, where the entire network is modelled within a computer, this type of empirical simulation is visible on the network, and you can communicate with the simulator over the network.