The existing communication structures are mainly based on wireless networks which were first introduced back in the 1980s. These cellular systems, such as CDMA (Code Division Multiple Access) and GSM (Global System for Mobile Communications), have evolved into various forms and currently used in everyday life. Wireless networks are used in many different fields, such as banking, business, and education.

There has been an effort in the past decade to transform the current wireless communication structure to a form where it relies less on the availability of a supporting structure. Based on this idea, Bluetooth and ad-hoc wireless sensors were introduced. These technologies made scientists able to review an old concept of mobile ad-hoc network.

A mobile ad-hoc network is a communications structure which can be formed by two or more mobile nodes without the intervention of any supporting infrastructure. Although this type of networking could be used for almost the same purpose as fixed wireless networks, there are still number of issues which await suitable answers. Among many of the existing issues is the ability to achieve reliable data transportation in an Internet-based mobile ad-hoc network.

This issue is gaining importance because mobile ad-hoc networks must satisfy the requirements of mobile computing and various commercial mobile Internet applications, future networking environments.

Some of the distinctive features of a mobile ad-hoc network are wirelessness and high mobility. The communications infrastructure of mobile ad-hoc networks mainly depends on the wireless links, in which every mobile node functions as a router, forwarding and receiving packets of information for all other nodes in the network. Internet applications, such as the Web browser and file transfer, use reliable data transport services. This transport service is supported by the TCP (Transmission Control Protocol). Transport Control Protocol was designed to support data transmission in fixed wireless networks.

Recent research recorded TCP's poor performance in a mobile ad-hoc network environment. This is because of TCP's inability to distinguish the cause of packet loss between network congestions during an active data transmission. In other words, TCP assumes that all of the packet losses are caused by network congestions and invokes congestion control and avoidance algorithms. TCP uses these mechanisms to alleviate network congestions through reducing the TCP transmission rate. One other factor is the high mobility in ad-hoc networking environments. This high mobility causes wireless links and route changes and breakages quite frequently in mobile ad-hoc networks.

There are a number of various approaches which can be used to resolve the performance degradation issues of reliable data transport in Internet based mobile ad-hoc networks. Some of the possible solutions might include modifying and improving link layer, network layer and transport layer protocols and eliminating the adverse interactions among these layers. Another solution is to enhance the inter-layer control and communications of control messages.

It's important to be able to connect a wireless ad-hoc network with a larger network like the Internet. We already have different facilities to provide various communications services for computer users. Current Internet configurations mainly depend on TCP for data transportation, which doesn't perform well on a mobile ad-hoc network. A lot of work has already been done to redevelop or modify the existing structure of TCP. This work needs to be refined and must be integrated into a single form to achieve reliable transportation of data in Internet based mobile ad-hoc network.

Dr. Humayun Bakht completed his Ph.D at the School of Computing and Mathematics in Liverpool at John Moores University. Prior to his current course of studies, he has successfully completed his MSc Software Engineering and BSc Electronics Engineering from University of Liverpool UK and Sir Syed University of Engineering and Technology in Karachi, Pakistan. Humayun's research interest is mobile ad-hoc networks, in particular, the development of a new routing algorithm for this type of networking. He can be reached at humayunbakht@yahoo.co.uk and you can visit his Web site at http://www.geocities.com/humayunbakht/.