This chapter describes the capabilities in ns to make the simulation topologies dynamic. We start with the instance procedures to the class Simulator that are useful to a simulation scriptSectionsec:userAPI. The next section describes the internal architectureSectionsec:nd-internal-arch, including the different classes and instance variables and procedures; the following section describes the interaction with unicast routingSectionsec:unicast-int. This aspect of network dynamics is still somewhat experimental in ns. The last section of this chapter outlines some of the deficiencies in the current realizationSectionsec:deficiencies of network dynamics, some one or which may be fixed in the future.
The procedures and functions described in this chapter can be found in ~ns/tcl/rtglib/dynamics.tcl and ~ns/tcl/lib/route-proto.tcl.