Event-synchronization protocol for parallel simulation of large-scale wireless networks

Abstract

An event synchronization protocol called time-based synchronization (TBS) is employed to control operation of a network simulation. In TBS, processors in the simulated network execute events based on comparisons between timestamps for each event and a value generated by a time tracking device in the processor. In this manner, event execution is not dependent on other processes in the network and the simulation can actually be carried out at speeds faster than real time. A multiprocessor network is specially designed to execute TBS-based simulations.

Description

CROSS REFERENCE TO RELATED APPLICATIONS[0001]This application claims priority under 35 U.S.C. 11 9(e) on U.S. Provisional Application No. 60 / 568,259, which was filed on May 6, 2004, and is hereby incorporated by reference.[0002]This application is also related to a U.S. patent application entitled Sensor-Network Processors Using Event-Driven Architecture, which is being filed concurrently herewith on May 6, 2005.GOVERNMENT SPONSORSHIP STATEMENT[0003]This invention arose out of research sponsored by a United States Government Agency, the Office of Naval Research (ONR), under ONR Contract No. N00014-00-1-0564. The Government has certain rights in the invention.BACKGROUND OF THE INVENTION[0004]1. Field of the Invention[0005]The present invention relates in general to a conservative event-synchronization protocol, time-based synchronization, which is particularly suited for parallel discrete event simulation of mobile ad hoc wireless networks.[0006]2. Description of the Background Art[0...

AI Technical Summary

Benefits of technology

"The present invention introduces a new conservative event synchronization protocol called time-based synchronization (TBS). This protocol allows for faster network simulation by controlling operation based on a time scale rather than network size. The use of TBS-based protocol enables faster simulation speeds compared to real-time, depending on the processor architecture used. The TBS protocol works by allowing an LP to execute an event when a timestamp of the event is less than the elapsed real time (or scaled version thereof) since the simulation began. The protocol does not require a special processing system for operation, but a special multiprocessor architecture can be used to implement the TBS simulation protocol for maximum advantage of the speed capabilities. Each processor in the network has its own dedicated processor and a timer coprocessor that keeps track of the simulated time and notifies the processor when a timestamp notification occurs. The host computer for the network determines the rate of each LP processor's incrementer at compile time."

Problems solved by technology

A drawback to know MANET simulation protocols, such as the null-message protocol, is that the speed at which an LP can execute an event depends on the rate at which the LP receives messages from other LPs in the network.

However, for very large networks with hundreds or even thousands of nodes, such limitations can dramatically increase the amount of time necessary to run a network simulation.

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