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4.1 Simulator Initialization

When a new simulation object is created in tcl, the initialization procedure../ns-2/ns-lib.hSimulator::init performs the following operations:

The packet format initialization sets up field offsets within packets used by the entire simulation. It is described in more detail in the following chapter on packetsChapterchap:pformat. The scheduler runs the simulation in an event-driven manner and may be replaced by alternative schedulers which provide somewhat different semantics (see the following section for more detail). The null agent is created with the following call:
        set nullAgent_ [new Agent/Null]
This agent is generally useful as a sink for dropped packets or as a destination for packets that are not counted or recorded.