Network Protocols for Ad Hoc, Wireless Network with Multimedia Traffic

Advisor: Prof. Ron Sass

Ad hoc, wireless networks present special challenges to the design of network protocols. Mobility and multiple wireless hops on the path from a source node to a destination lead to communications that are subject to fading, high bit-error-rates and loss of connectivity. Protocols for ad hoc, wireless networks are further complicated when the traffic is multimedia data. Our objective in this project is to study the behavior of network protocols in computer simulation. Previous work has shown that communication exchanged between the MAC/data link layers and the network layer of a node leads to better network routing algorithms [Pursley, Russell, Staples, vol 17, no 5, 1999, JSAC]. We believe additional information exchanged between the application layer and the lower layers will also lead to overall improvements in network performance. For example, by separating and identifying MPEG video streams into a base layer and enhancement layers, intermediate nodes can immediately adapt outgoing traffic patterns to changing bandwidth conditions prior to notifying the source (which will ultimately adapts its rate). In the other direction, the lower layers can assist in resource reservation and provisioning by informing the higher layers of existing conditions. More than just bandwidth availability, this might include some measure of bandwidth fragility. Our simulation environment includes a front-end hardware setup, similar to the one used in [Krunz, Sass, Hughes 11(3) 1996, Int. J. of Comp. Sys. Sci. & Eng.] for generating multimedia traffic and an OPNET simulation of wireless communications network.

An undergraduate working on this project will develop a variation of an existing simulation, gather results and draw conclusions about the effect of their changes on the system. In essence, the student is exposed to all aspects of the research process. Because a large part of the infrastructure is in place, the undergraduate will be able to gain a lot of experience in a relatively short period of time.