Changes between Version 3 and Version 4 of PTVS_Tech
- Timestamp:
- Jan 14, 2010, 9:45:05 AM (14 years ago)
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PTVS_Tech
v3 v4 17 17 '''Structure''' 18 18 19 The VANET simulator we have developed is a discrete event simulator. The simulation time advances with a fixed time resolution after executing the application code for the current moment of the simulation time. More specifically, at every moment of the simulation time, all the current events are pulled from a queue of events, and handled in a random order. 20 19 21 The events queue can hold three types of events: send, receive or GPS. A send event for a specified node triggers the calling of the node’s procedure responsible for preparing a message. It also schedules the corresponding receive event(s) for the receiver(s) the simulator decides to deliver the message to, according to the network module. The receive event is associated either with a node, or with a group of nodes (broadcast) and it calls the appropriate handler in each of the receiving nodes. The GPS event is scheduled at a regular time interval for each node, in order to simulate the way a real VANET application collects GPS data periodically. 20 22 Besides these three types of events, the mobility module updates periodically the position of each node that is a vehicle, according to the vehicular mobility model. This model takes into account vehicle interactions (passing by, car following patterns etc), traffic rules and various driver behavior.