The advantages of WLAN technology in LAN

A wireless LAN can be used as an extension of a wired LAN or as an alternative to a wired local area network, so the wireless LAN provides a strong networking flexibility. The growth of the

Wireless local Area network (WLAN) technology began in the mid 1980s, and was created by the Federal Communications Commission (FCC), which provides authorization for public applications in the industrial, scientific and Medical (ISM) band. This policy facilitates the development and application of WLAN technology by enabling companies and end users to apply wireless products without the need for FCC licenses. Unlike a wired LAN, which is transmitted via copper or fiber, the wireless LAN uses the electromagnetic spectrum to transmit information. Like radio and television, wireless LANs use radio waves (Airwave) to send information. Transmission can be achieved by using a wireless microwave or infra-red, but requires the effective frequency used and the transmit power level standard within the limits permitted by government agencies.

Advantages of WLAN technology

WLAN refers to the wireless channel as the transmission medium of the computer local area network, is the computer network and wireless communication technology combination of the product, it is the wireless multiple access channel as a transmission medium, to provide the traditional wired LAN functions, can enable users to truly achieve at any time, Anywhere, at random broadband network access. WLAN technology makes the computer on the Internet mobile, and can quickly and conveniently solve the network channel connectivity problem which is not easy to realize by Wired way. WLANs use electromagnetic waves to send and receive data in the air without the need for cable media. Compared to wired networks, WLANs have the following advantages:

Easy installation: Wireless LAN installation is simple, it does not require construction permits, no wiring or excavation trench. Its installation time is only a fraction of the time the wired network was installed.

covers a wide range of areas: in a wired network, the placement of network devices is limited by the location of network information points. And the wireless local area network communication range, is not limited by the environment condition, the network transmission scope greatly widens, the maximum transmission range may reach dozens of kilometers.

Economic Savings: Because of the lack of flexibility in the wired network, network planners are expected to consider the needs of future development as much as possible, leading to a predetermined mass utilization of information points with low rates. And once the network development beyond the design planning, but also spend more money for network transformation. WLAN is not limited by the location of wiring contacts, with the flexibility of traditional LAN can not be compared to avoid or reduce the occurrence of the above.

is easy to extend: WLANs are configured in a variety of ways and are flexible to choose as needed. In this way, the WLAN is capable of a small network of only a few users to a large network of thousands of users, and can provide features such as "roaming" (roaming) that wired networks cannot provide.

High Transfer rate: number of WLANsAccording to the transmission rate has now been able to reach 11mbit/s, transmission distance can be as far as 20km or more. The WLAN, which is applied to orthogonal frequency division Multiplexing (OFDM) technology, can even reach the 54mbit/s.

In addition, wireless LAN is strong anti-interference, network confidentiality is good. For many security problems in wired LAN, it can be avoided in wireless local area network basically. And compared with the wired network, the establishment, configuration and maintenance of WLAN is easy, general computer workers can be competent network management work. Because WLAN has many advantages, its development is very fast. In recent years, WLANs have been widely used in hospitals, shops, factories and schools that are unsuitable for network cabling. The topology structure of the

WLAN

WLAN has two main topologies, namely, the Self-organizing network (that is, the Peer-to-peer network, the commonly called Ad-hoc Network), and the Infrastructure Network (infrastructure network). Self-organized WLAN is a peer-to-peer model of the network, which is built to meet the temporary needs of the service. The self-organizing network is made up of a set of wireless terminals with wireless interface cards, especially mobile computers. These wireless terminals are directly connected to each other in the same workgroup name, extended Service Set identification number (essid) and password, and within the WLAN coverage, point-to-point, or point-to-point communication.