Wireless Networks - Introduction

Wireless LANs can be implemented internally or externally. Internal wireless LANs are generally used as an alternative to structured cabling systems. They are particularly desirable in areas where mobility is a requirement. For instance this could be a hospital ward, where a doctor uses a laptop to access patient records as he moves from bed to bed. In such a situation it would be impossible to use a cabled system. Internal wireless LANs consist of Access Points which act as a bridge between the wireless network and the fixed LAN and wireless client cards which connect the user to the wireless network. The client cards are fitted into PCs or laptops and connect via wireless to the Access Point, which in turn connects them to the fixed network.

External wireless LANs are predominantly used for building-to-building connectivity. With a range of up to 15 miles, wireless LAN provides a very cost effective alternative to leased lines for building-to-building connectivity. A key requirement for this technology is that there be line of sight between the buildings. Because 802.11b wireless is unlicensed the client only incurs a once off cost for the equipment. This is in sharp contrast to the setup costs and annual recurring charges associated with leased lines. The wireless LAN devices used for building-to-building connectivity are wireless bridges.

Technology

Wireless Networks - Introduction