WiFi Technology By Marc Bailey What is WiFi

Wi-Fi Technology By Marc Bailey

What is Wi-Fi? • Wi-Fi or Wireless Fidelity is a wireless technolgy owned by the Wi-Fi Alliance (formed in 1999) • Goal: Improve the use and exchange of information on wireless local area network products • Uses the Institute of Electrical and Electronics Engineers (IEEE) 802. 11 standards

802. 11 Standards • 802. 11 a - High frequency - More “flexible” and “reliable” - (Tomsho, Tittel, & Johnson) - Problematic with upgrades from the 802. 11 b standard • 802. 11 b - Most common - Longest in use

802. 11 Standards (cont. ) • 802. 11 g - High frequency - Backwards compatible with 802. 11 b

How does Wi-Fi Work? • Rather than using wires to connect, Wi-Fi uses radio waves as the medium • Extention to Ethernet • Range is several feet to serveral hundred feet (depending on environment and interference) • OSI Model: Physical Layer

Using Wi-Fi • Devices: PCs, game consoles, cell phones, mp 3 players, and PDAs • Network Design: Hotspots and Mesh Networks • Peer-to-peer: Consumer electronics and gaming • Who uses it? : Consumers with Wi-Fi technology and businesses

Hotspots • Localized wireless access areas • Various locations: Train stations, airports, coffee shops, universities, etc. • Commerical Hotspots - Portals for authentication and payment - Payment options (credit card, Pay. Pal, etc. ) - Smaller buisnesses may offer free service Examples: Hotels and small airports

Hotspots (cont. ) • Free Hotspots - Open public network with a Wi-Fi router - Can be a closed public network with the right software that protects and manages the network • A security issue especially when dealing with an unsecured hotspot

Wi-Fi Pros • No wires for machines • Good for places that are difficult to get cables into • Drops in price • Interoperable: Works anywhere a Wi-Fi connection is available since Wi-Fi is a global set of standards

Wi-Fi Cons • Wi-Fi channels used not the same worldwide • High power consumption • Limited range (but can be improved by antennas) • Wi-Fi pollution: High number of access points in one area can lead to interference

Security Options • Service Set Identifier (SSID) - Uniquely identifies the wireless LAN with a configured alphanumeric label. • Wired Equivalency Protocol (WEP) - A widely available data encryption. It does have the chance of being cracked by a motivated attacker. • Wi-Fi Protocol Access (WPA) - An upgrade over WEP in terms of security. The data encryption is harder to crack due to the key automatically changing periodically.

Security Options (cont. ) • 802. 11 i or WPA 2 - Similar to WPA, but incorporates more advanced data encryption. • Mac Address Filtering - Limits which computers can use the network based on their MAC addresses. Not practical for large networks.

Security: Hotspots • Most are unsecured • Even though it is costly, Virtual Private Networks (VPN) can be used • Some companies provide downloadable WPA support • Indentity theives and other criminals can set up a free public hotspot to steal valuable information. Commonly known as a “poisioned hotspot”

Video http: //www. youtube. com/watch? v=n 2 WSg 2 ibt. Hc

References • Guide to Networking Essentials - Fifth Edition by Greg Tomsho, Ed Tittel, & David Johnson • http: //www. wi-fi. org/ • http: //en. wikipedia. org/wiki/Wi-Fi