There are currently two types of mobile wireless networks. The first is known as infrastructured networks, such as networks with fixed and wired gateways. The bridges for these networks are known as base stations. The second type of wireless network is the mobile ad-hoc network. Ad-hoc connectivity is based on peer-to-peer communication.

The mobile ad-hoc network is a collection of wireless mobile hosts dynamically establishing a short lived network without the support of a network infrastructure. In this type of environment, it's expected that a large number of ad-hoc connections will exist in the same region without any mutual coordination. Mobile ad-hoc networks are the future of wireless networks. Nodes in these networks will generate both users and application traffic and perform various network functions.

Future mobile ad-hoc networks will use mobile routers to provide Internet connectivity to mobile ad-hoc users. A mobile router will also allow mobility of an ad-hoc network, where mobile users may use an Internet access within an ad-hoc network domain. Recently, organizations have begun to see potential for such dynamic networks. Mobile ad-hoc networks are of increasing interest for a distributed set of applications, such as distributed collaborative computing, distributed sensing networks, potential fourth generation wireless systems, and response to incidents that destroyed the existing communication structure.

There is current and future need for dynamic ad-hoc networking technology. The emerging field of mobile computing, with its current focus on mobile IP operation, will expend gradually. In the future, mobile computing will require highly-adaptive networking technology to manage multi-hop clusters that can operate autonomously and possibly be able to attach at some point to the bigger network.

In conclusion, wireless networks can be deployed in either infrastructure-based mode or on an ad-hoc basis. Although work is being done and prototype protocols are available for experiments, mobile ad-hoc networks still have difficulties. While some basic network control functions and routing procedures have been developed, many other issues require attention. Rapidly changing topology, network partitions, higher error rates, collision interference, bandwidth constraints, and power limitations together pose new challenges in network control; especially in the design of higher level protocols for routing and in implementing applications with quality of service requirements.

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/.