Wireless Network

WIRELESS NETWORK

Wireless network refers to any type of computer network that is not connected by cables of any kind. It is a method by which homes, telecommunications networks and enterprise (business) installations avoid the costly process of introducing cables into a building, or as a connection between various equipment locations. Wireless network uses radio frequencies to transmit data through the air. This means that if you have a laptop user who wishes to be mobile within the office, you can allow her to access the network through a wireless access point as long as she has a wireless network card in her laptop.

There are two types of wireless networks you can create: an ad hoc mode wireless network or an infrastructure mode wireless network. Each of these is known as a wireless mode, and each has its advantages.

 With ad hoc mode the wireless device, such as a laptop, is connected to other wireless devices in a peer-to-peer environment without the need for a wireless access point. With infrastructure mode, the wireless clients are connected to a central device, known as a wireless access point. The wireless client sends data to the access point, which then sends the data on to the destination, as mentioned previously; the wireless client can access network resources on the wired network once connected to the access point because the access point has a connection to the wired network.           

The advantage of ad hoc mode is that you don’t need to purchase the access point, but the benefit of infrastructure mode is that when you use the wireless access point you get to control that can connect to the wireless network and filter out types of network traffic. For example, if you use a wireless access point to allow wireless clients to connect to the Internet, you can control which web sites the users can connect to. This type of centralized control makes infrastructure mode extremely popular.

 

A typical wireless network running in infrastructure mode.

           

TYPES OF WIRELESS NETWORK

Wireless PAN

Wireless personal area networks (WPANs) interconnect devices within a relatively small area that is generally within a person's reach. For example, both Bluetooth radio and invisible infrared light provides a WPAN for interconnecting a headset to a laptop. ZigBee also supports WPAN applications. Wi-Fi PANs are becoming commonplace (2010) as equipment designers start to integrate Wi-Fi into a variety of consumer electronic devices. Intel "My Wi-Fi" and Windows 7 "virtual Wi-Fi" capabilities have made Wi-Fi PANs simpler and easier to set up and configure

Wireless LAN

A wireless local area network (WLAN) links two or more devices using some wireless distribution method (typically spread-spectrum or OFDM radio), and usually providing a connection through an access point to the wider Internet. This gives users the mobility to move around within a local coverage area and still be connected to the network. Most modern WLANs are based on IEEE 802.11 standards, marketed under the Wi-Fi brand name.

Wireless LANs have become popular in the home due to ease of installation, and in commercial complexes offering wireless access to their customers; often for free. Large wireless network projects are being put up in many major cities: New York City, for instance, has begun a pilot program to provide city workers in all five boroughs of the city with wireless Internet access.

Wireless MAN
A metropolitan area network (MAN) is a computer network that usually spans a city or a large campus. A MAN usually interconnects a number of local area networks (LANs) using a high-capacity backbone technology, such as fiber-optical links, and provides up-link services to wide area networks (or WAN) and the Internet.

Wireless WAN

Wireless wide area networks are wireless networks that typically cover large areas, such as between neighboring towns and cities, or city and suburb. These networks can be used to connect branch offices of business or as a public internet access system. The wireless connections between access points are usually point to point microwave links using parabolic dishes on the 2.4 GHz band, rather than omnidirectional antennas used with smaller networks. A typical system contains base station gateways, access points and wireless bridging relays. Other configurations are mesh systems where each access point acts as a relay also. When combined with renewable energy systems such as photo-voltaic solar panels or wind systems they can be stand-alone systems.