Wireless LAN and Wireless Man

Wireless LAN and Wireless MAN

Wireless LAN:

Wireless solution enhances connectivity of Local Area Network to reach unlimited area. The benefits of a wireless Local Area Network are many. The cost included to lay and purchase cable to reach a computer or server in any corner of the office or location where LAN is necessary, the installations required in various rooms of a workstation or the connectivity of a network with another device. Cost included for all the above can be minimized or cut using a WLAN. For example, a doctor can enter details directly when he is with the patient instead of going back to a workstation and recollect the details for report. Accuracy of a profession increases with WLAN. Some other areas where WLAN has an edge over other systems are public spots inside a building and outside, warehouse, hospitals, and conference halls. Restriction free access is provided by WLAN irrespective of the actual location or distance between users of a LAN. WLAN abolishes the primitive method of cabling which consume space. Wireless Local Area Network does not have the limitation of constraining to various parameters. Radio Frequency -- RF signals are used to exchange information in a WLAN. These signals enable LAN to operate approximately in any place. (Ouellet; Padjen; Pfund, 2)

One of the most advantageous features of WLAN is the connectivity required in a conference hall. The expense incurred to wire a room, maintain the device and the necessity to install several data jacks can be avoided by using WLAN. An access point can be created in a conference hall where connectivity is established using an antenna to enable multiple users. The movement of stock in a warehouse and the software that tracks the goods stored in a warehouse can be fitted with WLAN for better monitoring of goods on a particular day. The application of WLAN in a hospital is an advantageous feature. The developments and details of a patient can be directly reported into the computer by the medical personnel at the hospital. There will be instant inspection into the past records of a patient and give appropriate medication. Network access is now extended by educational institutions and companies in indoor and outdoor common area for the public to access. This service is extended for additional productivity from the user. WLAN provides connectivity to professionals who are on the move. (Ouellet; Padjen; Pfund, 2)

Local area network is considered to be a series of nodes that are being linked towards each other by making use of properly described areas. Each node is attributed to a computer application or a device to locate the route of the connected path. Some of the commonly used Local Area Network technologies are "Ethernet, Gigabit Ethernet, Fast Ethernet, Token Ring and Fiber Distributed Data Interface." (Ouellet; Padjen; Pfund, 3) Networking can be divided into "Wide Area Network -- WAN, Metropolitan Area Network -- MAN and the Local Area Network - LAN." (Ouellet; Padjen; Pfund, 3) These networks differ from each other depending on the area covered. LAN covers a comparatively less space. The path defined for communication in LAN differ in the method it is implemented. Four different topologies used to define the path are mesh, ring, star and bus which have its own advantages and disadvantages. (Ouellet; Padjen; Pfund, 3)

Networking of a workstation can be implemented by considering the effect of topology on the network administration. A network with mesh as the topology connects every device or workstation is connected to all device or workstation within a network. It is an expensive method of topology which is also difficult to manage due to its vastness of network and connection points. A connection in a mesh topology is calculated as: [n x (n-1)]/2 where n stands for the number of device connected in the network and the division by 2 avoids duplication of counting the connections. Ethernet deployed in a LAN enable multiple accesses -- MA. "Multiple Accesses" is made possible in a network where many device or stations are connected to a cable but get a chance to communicate. (Ouellet; Padjen; Pfund, 5)

Ethernet provides equal opportunity to all users thereby restricting priority and monopoly over the network. Each user takes turn to avail facility according to the algorithm settings in the network. The attempt made by each user in a network is recorded by carrier sense -- CS. When a point in the cable is in use, another user will be in queue for its turn. The CS in an Ethernet records the delay caused to the user and the frame is discarded after fifteen unproductive attempts. Collision Detect -- CD in an Ethernet is the ability of the device or workstation to sense collision in the network. Collision takes place when two users communicate concurrently on the network. This phenomenon may also take place due to the longer distance of the workstation, a faulty device or a badly installed drive which does not qualify Ethernet standards. An enforcement signal is created among all workstations in the event of a collision to prevent further transmission of data into the wire. (Ouellet; Padjen; Pfund, 6)

Once the enforcement signal completes the process, the network resumes transmission of data as per the protocol. In a token ring or FDDI network, deterministic access controls the network medium to ensure equal chance for transmission. The quality of physical infrastructure of a network is very important. Good quality switches, routers, servers and gear may be fitted but if the network systems do not transmit efficiently it would be a failure. Networks may be connected using cable or fiber. The quality of cable may be further divided into copper, twisted, untwisted, shielded, unshielded, braided core or solid core. The quality of networking cable is essential in a Wireless LAN, which counts for the quality if connected to the prevailing local area network. Copper is a widely used networking cable. Twisted pair cables intertwined with copper cabling gives high speed in a network. (Ouellet; Padjen; Pfund, 6)

After installation of network as per prevailing policies, a client is authorized to use a wireless LAN in different ways. WLAN in enterprises enable them to use WLAN with full freedom though there will be restriction in terms of Internet accessibility extended to visitors in common area. WLAN accessibility in public area may be restricted through payment or by checking their account with WSP or by providing access considering the nature of service provided by a person. Authorization to use WLAN would also depend on the allowed duration to use a network and its expiration. WLAN provided to a conference room may be just an internet connectivity or connection to the network using a server to access information that would assist in a conference. This is sometimes a temporary set up to utilize only during conference. Security for a WLAN is basically based on confidentiality maintained among the users in a network. It is technically preserved through encryption and integrity of information transmitted is maintained through digital signatures by using methods for key refresh, key exchange and bootstrapping. (Sankar, 10) fundamental knowledge about LAN would assist to learn more about the functioning of a WLAN. Various components that constitute the connection of a computer to a LAN are NIC -- Network Interface Card, a switch or a hub that enable connectivity to other systems, a routers or a bridge that enable connection to Internet. These components are interconnected using a cable. The only constituent that does not form a part of WLAN is the cable. WLAN put the cables aside that run throughout the workstation at all possible lengths and breadths. WLAN gives the same efficiency and speed in connection similar to a LAN. The parts that comprise a WLAN are W-NIC, AP -- Access point or wireless hub and, the antenna and the cable if required. WLAN signals travel directly to the access point without touching the curves and turns as in a LAN. Line of sight mechanism is deployed in a WLAN. The knowledge of this mechanism is vital for the successful installation and operation of a WLAN. (Trulove, 18-19)

An understanding of the difference between LAN and WLAN is also essential to install WLAN. W-NIC in a WLAN should be put in the prescribed channel to get connected to the access point. WNIC can locate an access point by sensing through the signals though access point and WNIC are located in the same channel. There are many aspects of concern while installing a WLAN. Signal used in a WLAN to transmit information between various points in a network is similar to signals used in transmission of information in a radio. The frequency band of transmission stands between 2.4 GHz to 5.2 GHz. This level of signals in a WLAN can pass through walls and roof of a building but it will be restricted to pass through metal bodies like doors or air ducts. Signal may be transmitted freely in outdoor areas or it will be obstructed in the presence of a tree or building. These aspects should be considered while designing and implementing a network to gain maximum efficiency. (Trulove, 19-20)

The standard that defines the application of a WLAN is IEEE 802.11 WLAN standard. Though this is the basic standard amended ones define the additional prescriptions added to it like 802.11a or 802.11b. The capacity of a WLAN is defined by its basic compatibility. WLAN of the latest version comes with an 11 Mbps capacity which also means it adheres to the latest version 802.11b which defines the amount of information the network can contain and transmit. Full throughput of 11 Mbps cannot be achieved though the throughput is limited to 4.5 to 6 Mbps at maximum level which can be compared to 10 Mbps in a wired LAN connected through Ethernet. A WLAN kit is the best solution for easy installation in homes and offices. It has one or more W-NIC with an access point which contains in it an antenna and WLAN card which uses an access point and its circuit. Access points come with one or more provision for WLAN card and it is flexible to the usage of antennas placed outside the WLAN card. This costly method of wireless networking is usually installed in complication commercial settings and offices which requires more accessibility. The Wi-Fi logo in a WLAN card proves that the product is tested for operation in a network and adheres to the Wireless Fidelity standards. This is a method of self test to substantiate that various constituents of the product and function together. (Trulove, 20-22)

Wireless LAN is a convenient networking system in a complicated situation, but it still has certain limitations. Metallic instruments present in industrial setting block radio waves used to transmit information in WLAN. In such a situation WLAN is restricted to use inside the building or outside the building and not in both the settings. A solution to this kind of limitation is the installation of dual antenna AP where one is placed inside and one is placed outside the blocking phenomenon. X-ray equipment, thick stones in a building, trees and vegetation and the distance covered by a WLAN also obstructs the signal from free flow to various points in its radius of installation. (When do you need a wireless LAN?)

Wireless MAN:

Metropolitan area network or MAN connects several computer users attached to a network in a specified geographical region which is vast that that covered by a LAN or local area network but smaller that WAN or wide area network. Computers and servers connected through a network in a city forms a MAN. MAN can also be defines as a network or connection of a number of LAN in a specified geographical area. This is also called a campus network. (Kumar; Parameswaran; Jayalakshmi, 177) the function to operate and transmit data by Microwave Access Forum is abbreviated as WiMAX. The advantages of this wireless technology that use IEEE 802.16 is unknown to several service providers and operators. WiMAX is a revolutionary accessibility provided by wireless broadband engineering. WiMAX was constituted to enhance and certify the adherence of components and systems formed on the basis of 802.16 stipulations to design systems that find a place in the market. The Fixed Broadband Wireless Access systems which use 802.16 standard for air interface is also called IEEE Wireless MAN air interface. (Bedell, 474)

The application of IEEE Wireless MAN air interface is essentially in multimedia where the wireless network covers a distance of up to 30 miles where wireless solution can be provided in the most complicated situations. The technology has evolved from the primary methods of cabling, DSI and the DSL to provide wireless connectivity with good performance in Metropolitan Area Network. This technology fills the space in the present broadband in use and gives an innovative technology which is easy to use, efficient and less expensive. The service offered by WiMAX is a generation next finding with a creative, strong, systematic and an upgraded method of WLL --Wireless Local Loop idea totally different from earlier technologies. Wireless MAN solution came into effect in 2003 when 802.16a was recognized by IEEE where bands ranging from 2 GHz to 11 GHz were covered. (Bedell, 474)

The IEEE 802.16 standard came out in 2002 with a band transmission ranging from 10 to 66 GHz. This provides various services to people who buy them. WiMax form of wireless broadband is also compared to a wireless DSL. The technology is at its budding stage where associates of the WiMax forum are studying the viability of the technology in the market. WiMax has not reached the position of a Wi-Fi. Wi-Fi evolved from the 802.11 standard whereas WiMax has evolved from 802.16 standards. Wi-Fi was considered to be used remotely by has now gained more and more users. (Bedell, 474) Similar is the case expected of WiMAX. Members of WiMAX forum which exceed 100 numbers are pooling the advantages of the technology to bring out a product that would be receptive globally. A well developed product from the WiMAX technology which is in its developing stage will contribute to a huge market if it is designed efficiently. The intention of the forum is to synchronize a wide range of device that can operate together to give better results. The forum also calls for to test the product at third party laboratory to substantiate the standard and function of the device. (Bedell, 481)

The product developed through WiMAX envisages putting together lap top and other devices which give the output or end result. A combination of Wi-Fi which is prevalent with WiMAX will open a new era for wireless transmission of information and the output from the required device. Subscribers and dealers of WiMAX benefit from the advantages of the product financially. The user can choose from a range of standard device by using wireless broadband. Finance does not get locked up with one particular supplier of wireless access. Since there would be more players, the user can chose the best option available from product which is upgraded from time to time in better versions. More manufacture leads to reduced cost and better performance. Wireless internet service proves to be economical to users around the world. The speed and efficiency of wireless technology that use 802.16a is a good choice for commercial establishment, offices as well as public internet providers who can rely on the speed and cost of connectivity. This is also advisable where wired connection is a bane. Wireless broadband internet connection is crucial for many establishments which can enhance their business opportunities with its advantages. The advantage also includes the time taken to install a wired connection or DS1which takes as long as three months. (Bedell, 482)

Wireless connections can be made instantly. A disconnection can also be effected at a faster pace resulting in no monetary loss to the provider and the user. The use of 802.16a technology provides high speed connection where a hundred or thousand users can work uninterruptedly. A request from an individual or commercial establishment can be materialized in no time by guaranteeing the satisfaction level of a user. Anyone who installs a wireless broadband or undertakes a business as provider ventures into a new world of profitable business. The cost incurred by earlier connectivity methods like wired service or connection through telephone has resulted in disadvantages around the world. It includes non-accessibility to broadband connection and non-subscription to existing modes of connectivity. (Bedell, 483)

Wired connectivity faces limitations in certain areas due to topography or distance. Cabling involves costs which are expenses for trenching and cabling where recovery of the money spent is a long process. Even if prospective subscribers are marketed to make a bulk connection in an area cost incurred to supply connectivity will not break even. WiMAX is an affordable version in terms of installation and use. The evolution of the technology to 802.16e will open wider opportunity for mobile users of broadband connectivity. On standardizing the WiMAX technology it will open opportunities for more players to enter the game in manufacturing enabled products. Subscribers and providers benefit out of the flexibility in choice. Line of sight aspect will vanish with the deployment of WiMax connection which is a solution to all the earliest versions of internet connections. It is most essential for developing countries that build technology related infrastructure. Efficiency and cost effectiveness are the core features of WiMAX. The gap left behind by DSL and DS1 will be filled with the more efficient WiMAX where distance is not a factor to get connectivity. WiMAX can reach rural areas and less populated region. It is also essential in government organizations and offices where WISP is used to access Internet. (Bedell, 484)