What is WLAN
WLAN or a wireless local area network is an internet network in which a wireless connection is provided to the end user via radio transmission of Internet Protocol (IP) packets between the network and the host computer. Such a network utilizes the electromagnetic bands in the radio and infrared region for the transmission of wireless signals through various spread spectrum technologies.
The three major components of a WLAN are:-
Wireless client receiver that provides the functionality in the Physical and MAC layer of the OSI framework of the network. Now a days most laptops comes with in built wireless client receivers because of the ever increasing popularity of Wi-Fi services. Antennas for the conversion of wired signals in to the electromagnetic waves and vice-versa. A few examples are: – Parabolic Antennas, Yagi Uda Antennas, Sectorized Antennas, Omni directional antennas etc. Access Points that are used to provide a client with wireless access in to the network. These basically function in three modes: – Root Mode, Repeater Mode and Bridge Mode. In root mode, AP’s are used for wireless connectivity between a client and the network. In repeater mode, AP’s are used for wireless connectivity between a client and an AP working in the root mode. Therefore this mode is utilized to increase the range of an AP working in a root mode. In the bridge mood, AP’s are used for wireless connectivity between different segments of a network. No client utilizes an AP working in a bridged mood to enter in to a network.
The major technologies that are used in the wireless interface for the transmission of data packets in a WLAN network are:-
Direct sequence spread spectrum or Frequency hoping spread spectrum for the radio transmission of data packets. Multiple Access Collision Avoidance technology when a number of clients are accessing an AP.
The major advantage of a Wireless Network such as WLAN is the mobility it provides for the end user while he or she is accessing the network. This makes WLAN a much more popular alternative to other hard wired networks. Now days, most cell phones come with built in Wi-Fi receivers and thus can be used to access the internet in a WLAN network (provided they have obtained the proper authorization).
The oxymoron of this technology is the problem of data security. The problems like ease of access, rogue access points and ease in traffic monitoring poses a big problem when it comes to the matter of security. Though now-a-days more and more sophisticated encryption technologies and protocols are being developed to tackle this predicament.