Title: History-Based Collision Resolution of CSMA/CA

Speaker: Dongsoo Stephen Kim (Associate Professor of Electrical and Computer Engineering, Purdue School of Engineering and Technology, Indianapolis)

Abstract:
Supporting random access channels, the medium access control (MAC) protocol plays a critical role to the quality of communication channels. The MAC protocol in wireless local area networks (WLAN) and mobile ad-hoc networks (MANET) mainly relies on distributed coordination among mobile stations based on carrier sensing and prioritized inter-frame spacing times. This talk will introduce a novel decision-making scheme of the contention window in wireless communications. The proposed mechanism overcomes the rigidness of existing methods, preventing the useless fluctuation of contention windows, especially when a collision domain contains a large number of competing nodes and a channel noise is non-trivial. The method, namely H-DCF, adjusts the contention windows adaptively and gradually to reflect the current channel state among contending mobile stations. In the paper, we mathematically induces the network performance of the proposed method, which is supported by the extensive study of network simulation. Both analytical and empirical studies show that the method provides considerable benefits in terms of channel throughputs and packet delay.

Short Biography:
Dongsoo S. Kim is currently an Associate Professor of Electrical and Computer Engineering at Indiana Univ. Purdue Univ. Indianapolis.  His research interests includes: mobility modeling, communication networks, mobile ad-hoc networks, sensor networks, switching networks, quality-of-service of data networks, network capacity planning, real-time operating systems.
Dr. Kim is serving as a director of Center for Sensor and Ad Hoc Network at Indiana University, which was initiated as a hub of central Indiana for multi-disciplinary research in wireless communication networks ( www.csan-i.iupui.edu).
He is also serving the Institute of Electronics Engineers of Korea (IEEK), Journal of Ubiquitous Convergence Technology (JUCT) as a Co-Editor-in-Chief.