Modeling and Sensitivity Analysis of Reservation Based USAP Unicast Traffic in MANETs

S. Perumal, V. Tabatabaee, J.S. Baras, C. J. Graff and D. G. Yee

To appear in the Proceedings of the MILCOM 2009 "The Challenge of Convergence, Boston, MA, October 18-21, 2009.

 

Abstract

In this paper, we develop and evaluate models for estimating and optimizing various performance metrics for unicast traffic using the hard scheduling (virtual circuit connection-oriented) mode of the reservation based protocol USAP in mobile ad-hoc wireless networks. USAP (Unifying Slot Assignment Protocol) is a dynamic distributed resource allocation protocol for mobile multihop wireless networks where the channel is partitioned in time and frequency cells. USAP is used as the resource allocation protocol in Rockwell Collins wireless ad-hoc protocol suite for tactical battlefield and in the Mobile Data Link (MDL) layer of the Joint Tactical Radio System (JTRS). We model the hard scheduling mode of USAP using loss network models along with reduced link capacity that couple the physical, MAC, and routing layers effects. The models provide quantitative statistical relations between the loss parameters that are used to characterize multiuser interference and physical path conditions on the one hand and the traffic rates between origin destination pairs on the other. The key effect of multiuser interference on a link is modeled via reduced link capacity where the effects of transmissions and receptions in the link neighborhood are modeled using USAP reservation rules. We compare our results with simulation and obtain good results using our loss network models but with the reduced link capacity distribution obtained by simulation. We then compute the throughput sensitivities with respect to network parameters and use these sensitivities to improve network performance. We optimize network performance using both reduced link capacity model and simulation’s reduced link capacity distribution.