Packet flow controls over wireless networks

Abstract

Due to the continued growth of the Internet and the increasing speed with packet-switched technologies, packet data networks have become major trend in the network field. On the other hand, wireless communication environments have grown explosively in recent years. The success of cellular system has enabled voice communication to go outdoors and the wireless LAN technology makes it possible to access the Internet indoors without a cable. As a result, users would like to access electronic data and services anywhere, anytime, using portable and affordable wireless terminals. Due to these needs, wireless networks are quickly becoming an integral part of the Internet. Therefore, the efficient packet data transmission will be a very important in wireless networks such as 3G or 4G cellular systems and mobile ad-hoc networks. There are many researches to efficiently deliver data over the wired packet networks. Many fancy and effective flow control mechanisms have been proposed and implemented on the wired packet data networks like the IP domain network. However, we would not be able to use these mechanisms directly over a wireless network, which has many different properties from wired one. The wireless network has a high error rate, low bandwidth, fast fading, and sudden degradation in signal quality. These properties increase the cost of wireless resources and lead to characteristics like lossy link, variable delay, fluctuating bandwidth, and sudden channel blackout. Therefore I will research on efficient packet data flow control mechanisms for wireless networks in the transport and network layer. I have been researching in two parts: end-to-end TCP flow control in transport layer and per-packet flow control in network layer. In the first part, I work on TCP flow control mechanisms. The TCP, which consists mostly of Internet traffic, does not work well in a wireless network. Considerable research has tried to improve TCP performance in a wireless network, especial...