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CASE STUDY IMPLEMENTATION AND EXAMPLES OF WIFI



The Future of Hotspots: Making Wi-Fi as Secure and Easy to Use as Cellular
ABSTRACT
Wi-Fiis a local area wireless computer networkingtechnology that allows electronic devices to network, mainly using the 2.4 gigahertz (12 cm) UHF and 5 gigahertz (6 cm) SHFISM radio bands. The term "Wi-Fi" is used in general English as a synonym for "WLAN" since most modern WLANs are based on these standards. "Wi-Fi" is a trademark of the Wi-Fi Alliance. The "Wi-Fi CERTIFIED" trademark can only be used by Wi-Fi products that successfully complete Wi-Fi Alliance interoperabilitycertification testing.
Many devices can use Wi-Fi, e.g. personal computers, video-game consoles, smart phones, digital cameras, tablet computersand digital audio players. These can connect to a network resource such as the Internet via a wireless network access point. Such an access point (or hotspot) has a range of about 20 meters (66 feet) indoors and a greater range outdoors. Hotspot coverage can comprise an area as small as a single room with walls that block radio waves, or as large as many square kilometers achieved by using multiple overlapping access points.
According to the Wi-Fi Alliance, about 200 million households use Wi-Fi networks, and there are about 750,000 Wi-Fi hotspots worldwide. Wi-Fi is used by over 700 million people and there are about 800 million new Wi-Fi devices every year. Cisco has shipped over 11 million access pointsto customers worldwide.
IEEE 802.11 standard
The IEEE 802.11 standard is a set of media access control(MAC) and physical layer(PHY) specifications for implementing wireless local area network (WLAN) computer communication in the 2.4, 3.6, 5, and 60 GHz frequency bands. They are created and maintained by the IEEE LAN/MANStandards Committee (IEEE 802). The base version of the standard was released in 1997.
Internet Access
Wi-Fi technology may be used to provide Internet accessto devices that are within the range of a wireless networkthat is connected to the Internet. The coverage of one or more interconnected access points(hotspots) can extend from an area as small as a few rooms to as large as many square kilometers. Coverage in the larger area may require a group of access points with overlapping coverage.

Devices
A wireless access point (WAP) connects a group of wireless devices to an adjacent wired LAN. An access point resembles a network hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an Ethernet hub or switch, allowing wireless devices to communicate with other wired devices. Wireless adapters allow devices to connect to a wireless network. These adapters connect to devices using various external or internal interconnects such as PCI, miniPCI, USB, ExpressCard, Cardbus and PC Card. As of 2010, most newer laptop computers come equipped with built in internal adapters.
Range
The Wi-Fi signal range depends on the frequency band, radio power output, antenna gain and antenna type as well as the modulation technique. Line-of-sight is the thumbnail guide but reflection and refraction can have a significant impact. An access point compliant with either 802.11b or 802.11g, using the stock antenna might have a range of 100 m (330 ft). The same radio with an external semi parabolic antenna (15db gain) might have a range over 20 miles.
Securing Methods
            A common measure to deter unauthorized users involves hiding the access point's name by disabling the SSID broadcast. Another method is to only allow computers with known MAC addressesto join the network. Wired Equivalent Privacy (WEP) encryption was designed to protect against casual snooping but it is no longer considered secure. Tools such as AirSnort or Aircrack-ng can quickly recover WEP encryption keys. Because of WEP's weakness the Wi-Fi Alliance approved Wi-Fi Protected Access (WPA) which uses TKIP(Temporal Key Integrity Protocol). The more secure WPA2 using Advanced Encryption Standard was introduced in 2004 and is supported by most new Wi-Fi devices, WPA2 is fully compatible with WPA.

 

 Growing Data Demand\
In 2010, global mobile data traffic nearly tripled (it grew to be 2.6 times larger than the previous year) for the third year in a row, despite a slow economic recovery, increased traffic offload, and the advent of tiered pricing.
• Global mobile data traffic will increase 26 times from 2010 to 2015, a 92 percent compound annual growth rate (CAGR).
• The average mobile connection speed will increase by a factor of 10 from 2010 (215 kbps) to 2015 (2.2 Mbps), a 60 percent CAGR.
• The average mobile connection speed will increase 10 times from 2010 (215 kbps) to 2015 (2.2 Mbps), a 60 percent CAGR.
• By 2015, global mobile data traffic will reach an annual run rate of 75 Exabyte per year. 75 Exabyte is equal to 75 times more than all IP traffic generated in 2000, or 19 billion DVDs, or 536 quadrillion SMS text messages.

Next-Generation Hotspot
• Network discovery and selection: Mobile devices will discover and automatically select and connect to Wi-Fi networks based upon user preferences and network optimization.
• Streamlined network access:Mobile devices will be automatically granted access to the network based upon credentials such as SIM cards, which are widely used in cellular devices today. No user intervention will be required.
• Security: Over-the-air transmissions will be encrypted using the latest-generation security technology (Wi-Fi Certified WPA2-Enterprise). The key elements for Release 2 of the Wi-Fi Certified Pass point certification program, anticipated to launch in Q4CY2013, are as follows:
• Immediate account provisioning: The process of establishing a new user account at the point of access will be simplified, eliminating many user steps and driving a common provisioning methodology across vendors.
• Provisioning of operator policy for network selection: A mobile device's connection manager uses this policy to select the best Wi-Fi network to join when multiple networks are available.
Applications
·         Turn Your Smartphone into a Remote Control
·         Wirelessly Transfer Photos from Your Digital Camera
·         Stream Audio to Any Speakers in the House
 Conclusion
Wi-Fi networks are an essential component to meet the ever-growing demand for mobile broadband. The business value of Wi-Fi will continue to expand by offering users consistent, portable connectivity. What's more, that business value will be realized via seamless authentication, provisioning, and roaming.


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