Divested of all technical jargon, a wireless LAN (wireless Local Area Network) may be described as linking two or more computers or devices to facilitate inter- communication among the devices through radio connection within a limited physical area. The obvious purpose is to provide the users connectivity to the network while moving around the prescribed operational area.
Wireless LAN Technology and Connectivity
True to its name, a wireless LAN does not depend on the conventional wired Ethernet connections. A wireless LAN functions either as an independent system or is set up as an extension to an existing wired network. Feasibility reports suggest that a wireless LAN signal can be broadcast to effectively cover a maximum radius of 100 yards. Wireless LANs offer increased productivity, physical convenience, and cost advantages over traditional wired networks.
To obviate the requirement of wired connection, Wireless LAN uses Radio Frequency technology for transferring and receiving data through the air and makes the mobility concept of data connectivity feasible. It has, however, to be borne in mind that since the signal is broadcast within a closed area where many can share it, security concerns have to be properly addressed so that authorized users alone have access. Installing a wireless LAN system can be quick and simple. Also, the need of getting cable connections through walls and ceilings can be eliminated completely.
Types of WLAN
Wireless LANs are available in two basic types – the smaller version more appropriate for home offices with a couple of access points with provision to broadcast a signal of 100- to 200-foot radius. The second type, also called the enterprise class, provides for more individual access points to broadcast the signal to reach a much wider area.This type, by virtue of its expanded user capacity, carries some distinctive features like enhanced security, remote management, and the potential to integrate with other wired networks.
There is a wide variety of technologies for the manufacturers of wireless LANs to choose from when designing a wireless LAN system – Narrowband Technology, Spread Spectrum Technology, Frequency-hopping spread-spectrum (FHSS), Direct-sequence spread-spectrum (DSSS) and Infrared Technology – with each of these technologies having its own benefits.
Several protocols exist for wireless networking. They are:
802.11a: has data transfer rates up to 54Mbps and as it it operates in a more regulated frequency, is said to be less plagued by signal interference. This standard is faster than 802.11b and is capable of supporting multiple simultaneous connections.
802.11b:supports data transfer rates up to 11Mbps. Though it is proved to be more effective than 802.11a at penetrative powers, it does not support as many simultaneous connections.
802.11g:supports data transfer speeds up to 54Mbps. It is midway between 802.11 band and 802.11a for range capability and the typical range is between 65 to 120 feet.
802.11.n: supports data transfer speeds up to 300Mbps. It is the fastest and longest range protocol to date and is now standard fare on most new laptops and wireless adapters.