Wireless networks

The arrival of wireless technology has reduced the human efforts for accessing data at various locations by replacing wired infrastructure with wireless infrastructure and also providing access to devices having mobility .Since wireless devices need to be small and bandwidth constrained, some of the key challenges in wireless networks are Signal fading, mobility, data rate enhancements, minimizing size and cost, user security and (Quality of service) QoS. Speaking of Wireless LAN, the general thought is about data transfer while using applications such as web browser, e-mail client, etc. As the technology is advancing, Wireless LANs are now also capable of supporting time-sensitive services such as voice and video. These services have stringent service

requirements from the network infrastructure. These requirements supersede the requirements of general data. The wireless industry is undergoing a change. We see the evolution from cellular 2G to  3G standards, the migration from circuit to packet applications, and the procession of  voice to data. We also see the industry incorporating new wireless access technologies  such as WiFi and WiMAX. All of this is happening in a market place where voice subscriber penetration levels in many parts of the world are saturating and there is   incredible pressure to reduce network capital and operating costs. These conditions  present significant technology challenges to increase customer demand and further increase  network capacity to lower network costs .This paper is intended to provide the reader with an overview of the Research Issues and Challenges in wireless networks.