History About Wifi Technology Information Technology Essay

History About Wifi Technology knowledge Technology EssayABSTRACTIn many of the industrial sectors, the receiving aim meshing technologies ar gaining rapid eulogy because of its cost effectiveness, improved dependability and flexibility. The increase in the radio receiver net workings is one of the technological advances that are having a major impact on the manner we do business 10.This paper refers how Wi-Fi engineering is organized and somewhat of its applications and advantages over customary means. It also explores how Wi-Fi technologies communicate in the scatter spectrum and also its configurations. The Wi-Fi refers to the 802.11b piano tuner Ethernet shopworn that was intentional to defy the wireless LANs. The essential enabling engine room is the Wi-Fi engineering and it is the only practicable infrastructure for the abode which al kick mangles the user to extend their meshs for home entertainment. The most popular user approach path engine room is the Wi- Fi (WLAN/IEEE 802.11) because of its high bandwidth and low cost.Keywords radio set Fidelity, Wi-Fi, WLAN, wireless technologies, IEEE 802.11a/b/g, spread spectrum, configurations.IntroductionIn the recent years only, the wireless technology has grown rapidly which all(prenominal)ows the users much reliable, effective and throne access the internet without using the wire. Wireless mesh engagement topologys are more effectively utilise in many applications such as home entertainment, offices, communicate receiver, military areas and general places. The term wireless does non mean the disturbance or group of switches. Wireless means the chat without the use of wires opposite than the antenna, the Ethernet, and the ground taking the place of wires 2. For several industrial operations, wireless technology affords efficient and effective consortivity solutions. Using the wireless technology there are many benefits such as away facilities, processes and field operation whi ch results in improving productivity, downtime, faster and more accu number info collection.The term Wi-Fi technology is also referred as Wireless Fidelity. The Institute of Electrical and Electronics Engineers Inc. (IEEE) is the association liable for setting the standardizeds on how the technology and products works, operate and communicate 3. The 802.11 technology standards, demote known as Wi-Fi technology and it is being set up into the Broadband Wireless nark (BWA) equipment and Local Area Network (LAN) access points to quickly connect data processor to LANs and as well as internet service providers. The 802.11 standards are growing to supply a higher(prenominal) data rates and better quality of service. Wireless LANs operates on two frequencies such as wireless wave and infrared. In the past decades, the wireless access point has come into the market with infrared exclusively in todays world the radio frequencies are employ most popularly. The advantage of the radio w ave frequence is more penetrate with the walls, floors and doors but whereas the infrared device is on line of sight. Wi-Fi network connect computer to each other to the internet and to the wired network.1.2 History of WLANA WLAN is a local area network without wires and whereas a wired network in which the customers send/receive the data through and through the cables. The wireless network uses a radio wave frequency. As part of the erect family of the spread spectrum systems, the Wi-Fi technology uses single carrier direct-sequence spread spectrum radio technology and multi-carrier OFDM (Orthogonal Frequency Division Multiplexing) radio technology. In 1985, the unauthorized spread spectrum was first approved by the Federal Communications Commission (FCC) 5. In all major countries, these FCC regulations were later copied with enabling some changes in the use of this technology and these regulations were then enabled the growth of Wi-Fi technology according to requirements such as offices, online games and so on.In 1991, the Wi-Fi technology was invented by NCR corporation/ATT (later Lucent and Agere systems) in Nieuwegein, the Netherlands. Initially for the cashier systems, the first wireless product were brought on the market which is marked as WaveLAN with step on its of 1Mbits/s to 2Mbits/s. Vic Hayes, who was the first discoverer of the Wi-Fi and later has been named as Father of Wi-Fi, was involved in designing standards such as 802.11a/b/g. Wireless LANs communicate via the 2.4 GHz or 5GHz band with the unlicensed Industrial, Scientific and Medical (ISM) radio bands where cordless phones, instant monitor and other personal device potful also operate. accord to Mr. Phil Belanger of the Wi-Fi conglutination contradict the most popular conclusion that Wi-Fi stands for Wireless Fidelity 5.1.3 Benefits of WLANA new way to communicate with the user is through the WLANs while accommodating the way business is done. The following are the benefits achie ved through WLANsMobility within structure.FlexibilityLower cabling beTo set up temporary spaces, it is easierProductivity gainsReduced errorsbetter efficiencyImproved performance, efficiency and security for enterprise partners and guestsEasier to collaborateEasier adds, moves and changes and lower support and maintenance costsMore efficient use of office space.Wireless Fidelity (Wi-Fi) TechnologyThe IEEE 802.11 standard was projected for the WLANs. To wish the networking the short way for Wi-Fi is the wireless. Wi-Fi is easy to access and it is actually simple to connect to computer anywhere in the office or homes without the use of wires. Using the radio signals the computer connects to the network. In 1997, the first standard (802.11) was released and works in the frequency band at 5GHz with the data rate of 54Mbits/s and uses the OFDM (Orthogonal Frequency Division Multiplexing) intonation 4. The Carrier Sense Multiple Access/ Collision Avoidance (CSMA/CA) is the media acc ess method.The term 802.11.x terms is used to donate the set of amendments to the standard. Within the scope of one building and one room, we can connect to the wireless to the restricted signal shed (indoor range is approximately about 1m).skhema propose 1 Internet lodge with wire and without wire (Wi-Fi)At present, the best values of the bit rate have a networks knowing accordance with the 802.11n standard that has the typical naked as a jaybird data rate of 540Mbits/s 3. Wi-Fi network operates in the unlicensed with the 2.4 and 5GHz radio bands, with 11Mbps (802.11b) or 54Mbps (802.11a) data rate or some of the products have dual bands. Wi-Fi network uses radio technologies to transmit and receive the data at high speed.IEEE 802.11 is available in three modes- 802.11a, 802.11b and 802.11g. IEEE 802.11a/b/g actually describes three different wireless Ethernet standards which are currently implemented in industrial applications as well as commercial applications. These three al ternatives are based around the same physical mold of the OSI model and it also defines the bands on what the wireless network is used and also defines the modulation technique. IEEE 802.11 standards include Wi-Fi, W-LAN and Wireless Ethernet.IEEE 802.11aThis standard operation is used in OFDM which operates at a frequency of 5GHz band and thereby allowing the raw contagious disease data rate up to 54Mbps. It is introduced in 2001. For this band, some of the countries have other uses such as military and air traffic control, so therefore this band is not globally accepted and to be used in the ISM applications. But in some cases, this band can be used inside the building with limited power. In the U.S, the band 5GHz is treated as other 900MHz and 2.4GHz ISM bands. single advantage of the IEEE 802.11a is that it operates with same data rate (54Mbps) as IEEE 802.11g but it escapes sometimes due to crowded with the 2.4GHz channels. slight interference in the 5GHz band appears means the potential for more reliable transmission. The theoretical speed of this standard is 54Mbps but the raw transmission rate of this standard is in between 15-20 Mbps. The range of this standard is 50-75 feet. This is not compatible with 802.11b and it is more expensive.IEEE 802.11bThis standard was implemented in 1999, uses 2.4GHz band with the DSSS (Direct Sequence Spread Spectrum) modulation. The maximum transmission rate of this standard is 11Mbps within 30m range. It is most popular and least expensive. But the actual speed of this standard is 4-6 Mbps. The range of the wireless is 100-150 feet. The subsection of this standard is called Wi-Fi.IEEE 802.11 gThe OFDM technology of 802.11a is adopted in this standard and which is globally accepted with 2.4GHz band. Using the OFDM technique these data rates increased to 54Mbps over the air. It is important that 802.11g is compatible back with 802.11b. But this standard is more expensive so prefer to go for the least expensive and better performance which is 802.11b.Components of Wi-FiIn order to access the Wi-Fi, we require some of the components such as adapters, access point, Wi-Fi antenna, Wi-Fi Bridge, PCI card game that accept wireless PC cards and external USB wireless NICs. The following are the component figuresaccecpoint.jpg normal 2 Access horizontal surface Figure 3 Adapterswifi antena.jpg wifi bridge.jpgFigure 4 Wi-Fi aerial Figure 5 Wi-Fi BridgeFigure 6 PCI cards that accepts wireless PC card Figure 7 External USB wireless NICsHow Wi-Fi network works?Wi-Fi network uses the radio waves to communicate each other among devices. The basic concept of the Wi-Fi network is same as the walkie talkies. An access point to the internet connection can be installed through the Wi-Fi hotspot. This access point acts as base station. With this access point, an antenna is physically machine-accessible to conventional wired Ethernet network and serves as a bridge to the wireless network. A device encounters t he hotspot when the Wi-Fi is enabled and the device can connect to that network wirelessly. Between the lymph node systems, the Wi-Fi can also support conversation and allowing the devices to communicate with one another during the confederate-to-peer method.A Wi-Fi 802.11b typically can transmit the maximum data rate up to 11Mbps with an approximation range of 150 feet. Beyond that distance, the signal fallback very slow up to 5.5 Mbps, 2Mbps and 1Mbps and this slower speed can move the signals as far as 1500 feet. The actual performance of the network depends upon the signal pattern and the number of obstacles in the area. To indicate the wireless within the area, an access point itself announces through broadcasting, a serving Set Identifier (SSID) approximately 10 times per second. The SSID indicates the name of the network. PCs that are within the range and has equipped with wireless network interface card can receive the SSID, associate with WLAN and necessitate an IP add ress that will allow them to connect to the local network, surf the internet and view network folders 4.Wi-Fi Network TopologiesAccess Point (AP) in the Wi-Fi may vary greatly depending upon their cost but in some of the cases these AP gives selection for roaming where the wireless clients can switch from one AP to another. There are three kinds of network topologies.AP (Access Point)-based topology ( theme Mode)Peer-to-Peer topology (Ad-hoc Mode)Point-to-multipoint bridge topology.AP-Based TopologyAccess Point (AP) is the wireless component through which the client can communicate. Access point is the device that contains standard IEEE 802.11 conformant MAC and PHY interface to the wireless medium and provides access to the distribution system for associated stations. Through an AP, BSA-RF (Basic Service access is the area of the radio frequency (RF)) coverage is provided. ESA (Extended Service Access) consists of two or more BSA. In order to allow the roaming, ESA cell consists of 10-15% overlap. The following figure shows the AP-based topology 9.Figure 8 AP-Based topologyPeer-to-Peer TopologyIn this topology, the access point is not essential. Within the cell, the client devices can communicate directly with one another. This topology is useful in setting up the wireless network very quickly and easily. The following figure shows the peer to peer method.Figure 9 peer-to peer methodPoint-to-multipoint bridge topologyThis caseful of topology is used in buildings from one to another building apart within the miles. This is required to connect a LAN in one building to a LANs in another building. A clear line of sight is achieved among buildings under these conditions. Based on the type of antenna and wireless bridge used the line-of-sight range varies and as well as in environmental conditions. The following figure shows the point to multipoint bridge topologyFigure 10 point-to-multipoint bridge topologyAccess Point and Wireless Card are the two ways that can use for the networking.Ad-hoc In this method, the total wireless cards are used from peer-to-peer network and there is no access point (AP).Infrastructure All wireless cards connect to the central access point that provides them connectivity with each other as well as wired network 1.Wi-Fi ConfigurationsA Wi-Fi network is very simple and can be easily set up to the homes and offices that allow the network to share the files, printer and so on.Figure 11 Wireless network set upThe public Wi-Fi hot spots are rapidly worthy common in airports, business, hotels, libraries and so on.Wi-Fi SecuritySecurity is one of the first disquiet of people deploying a wireless LAN, the 802.11 has addressed the issue through providing what is called WEP ( pumped-up(a) Equivalent Privacy). The main concerns of the users are that an intruder would not be able to access the network resources through similar wireless LAN equipment and be able to cause the wireless LAN traffic (eavesdropping).There are two primary components which are required for Wi-Fi network security to be broken down.AuthenticationPrivacyThere are two types of authentication is required first is user authentication and second is server authentication.Authentication means keeping the unauthorized users off from the network. In user authentication server, the username and password is required. This authentication has a risk as well as a solution in sending the data. The risk one is the data is send before the ripe channel is established and level to passive eavesdropping by attackers. The solution for this is, before sending the username and password, encrypted channel is established. second in server authentication, the digital certificate is used and within the client software the validation of the digital certificate occurs automatically.Wireless Protected Access (WPA) is a standard based specification, interoperable security enhancement that strongly increase the level of data protection and for existing a ccess control and future wireless LAN systems.Wi-Fi ApplicationsWi-Fi technology is simple and easy to access the network without the wire. At present, the Wi-Fi is most popular technology that has been used in the market. There are several applications through the Wi-Fi technology. It is used at homes, office, small businesses, large corporations and campuses, health care, wireless ISP (WISP) and travellers.Advantages and Disadvantages of Wi-FiAdvantages of Wi-FiIt allows the LANs to be set up without cabling and also it reduces the costs and expansion of the network.Wi-Fi network support roaming such that a laptop can move from one access point to another.Wi-Fi is global set of standards.MobilityEase of installationReliability and FlexibilitySecurityUse unlicensed part of radio spectrumDisadvantages of Wi-FiIt can access to limited range.Higher power consumptionThe most common wireless encryption standard, Wired Equivalent Privacy (WEP) has been broken even if the correct configur ation is set up.InterferenceTypically, Wi-Fi Access Point is set to default to an open (encryption-free) mode.ConclusionIn the past few years, the Wi-Fi technology is growing very rapidly in the rural development areas. In the rural areas, the technology has been helped the consumers in receiving the high speed internet service. All through urban environment the Wi-Fi hot spots are becoming more popular. When the Wi-Fi technology has brought up to the rural and urban areas the broadband internet access price has been drive down. According to the various industrial applications, the network connectivity for the industrial wireless solution provides that is cost effective and efficient. To ensure the reliability of wireless connectivity and safety of industrial operations, a hazardous area classification is necessary that provides the redundant cerebrate radio. Currently, there are several standard-based wireless technologies that are used for the industrial applications for the fiel d sensors networking such as ISA100, WHART and ZigBee. Wi-Fi technology is simple and easy to deploy to the network. The IEEE 802.11 is the standard used for the Wi-Fi hot spots.With appropriate security features, industrial hardware and industrial interface products, Wi-Fi technology has a certain association of commercial technology, based on the 802.11 technology and is becoming a solution for many industrial communications and networking.