Network definition file created by OmniNET++, a software package used for building network simulators; stores the network topology structure; used for describing the logical structure of the network that will be simulated in the software.

NED files do not specify the behavior of the network. Instead, they behavior is defined by a complementary C++ source code file (.CC or .CPP file). Once a NED file and the corresponding C++ behavior file are created, the network can be simulated. Network description files can be created using a plain text editor, or by using the OMNeT++ IDE, which is included with the OMNeT++ download package. NOTE: OMNeT is also referred to as "omnipp," where "pp" stands for "plus plus."