WI-FI and Wi Max


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WI-FI and Wi Max

  2. 2. Wi-Fi      Stands for Wireless Fidelity. Brand licensed by the Wi-Fi Alliance. Wi-Fi is a local area network technology that was originally thought to replace the thousands of miles of LAN cables. Wireless Local Area Networks (WLAN) Based on IEEE 802.11
  3. 3. IEEE  In 1997, the Institute of Electrical and Electronic Engineers (IEEE) drafted the 802.11 standard for wireless local area networking.  In 1999, networking hardware companies accepted the standard and began manufacturing products using the 802.11b protocol which operated in the 2.4 GHz range and was capable of transmitting at speeds of 11 Mbps.  The 802.11a protocol was also released in 1999, operating at 5.8 GHz with transmissions speeds of 54 Mbps, but its cost was prohibitively high.
  4. 4. IEEE Wireless Standards Wireless Standard 802.11b 802.11g 802.11a Frequency Range 2.4 – 2.4835 GHz 2.4 – 2.4835 GHz 5.725 - 5.850 GHz Max Speed 11 MBPS 54 MBPS 54 MBPS Max Encryption 128 bit WEP 128 bit WEP 152 bit WEP 256 bit AES Discrete Channels 3 3 8 Natively Compatible 802.11b, 802.11g 802.11b, 802.11g 802.11a Potential user Entry level and home networks Larger networks, small business Large business concerned with security
  5. 5. Sample Wi-Fi Illustration
  6. 6. Wireless network design Any wireless network can be thought of as a combination of one or more of these types of connections: • Point-to-Point • Point-to-Multipoint • Multipoint-to-Multipoint
  7. 7. Point to Point The simplest connection is the point-to-point link. These links can be used to extend a network over great distances.
  8. 8. Point to Multipoint When more than one computer communicates with a central point, this is a point-to-multipoint network.
  9. 9. Multipoint to Multipoint When any node of a network may communicate with any other, this is a multipoint-to-multipoint network (also known as an ad-hoc or mesh network)
  10. 10. WLAN Architecture—Ad Hoc Mode  Ad-Hoc mode: Peer-to-peer setup where clients can connect to each other directly. Generally not used for business networks.
  11. 11. Ad Hoc Structure Mobile stations communicate to each other directly. It’s set up for a special purpose and for a short period of time. For example, the participants of a meeting in a conference room may create an ad hoc network at the beginning of the meeting and dissolve it when the meeting ends.
  12. 12. WLAN Architecture--Mesh  Mesh: Every client in the network also acts as an access or relay point, creating a “selfhealing” and (in theory) infinitely extensible network.  Not yet in widespread use, unlikely to be in homes.
  13. 13. Wi-max WiMAX uses radio microwave technology to provide wireless internet service to computers and other devices that are equipped with WiMAX compatible chips for example PDA’s, cell phones etc. It works more or less like cellular network technology. The theoretical range of WiMAX is up to 30 miles and achieves data rates up to 75 Mbps WiMAX operates in similar manner as Wi-Fi but with two very convincing differences as compared to Wi-Fi, these are : o Data rate o Data range
  14. 14. WIMAX / IEEE 802.16 Wimax networks refer to broadband wireless networks that are based on the IEEE 802.16 standard, which ensures compatibility and interoperability between broadband wireless access equipment .  The IEEE 802.16 standards define how wireless traffics move between subscriber equipment and core networks.  WiMAX was designed for the transmission of multimedia services (voice, Internet, email, games and others) at high data rates. Source: SHASHI JAKKU
  15. 15. Features Use microwave for the wireless transfer of data. Specifies a frequency band in the range between 2 GHz to 66 GHz. For high speed wireless networking. Basically, Wimax is a wireless internet service that is capable of covering a wide geographical area by serving hundreds of users at a very low cost. Uses OFDM ,good for multipath environments. It includes TDD and FDD duplexing support. Flexible channel sizes (3.5 MHz,5 MHz,10MHz) An easy and fast system to install. Leading to low installation cost, when compared to fiber ,cable or DSL deployments.
  16. 16. 802.16 STANDARDS 802.16.1 : (10-66 GHz, line-of-sight, up to 134Mbit/s). 802.16.2 : (minimizing interference between coexisting WMANs). 802.16a : (2-11 Ghz, Mesh, non-line-ofsight). 802.16b : (5-6 Ghz). 802.16c : (detailed system profiles). P802.16e : (Mobile Wireless MAN).
  17. 17. WIMAX System A WIMAX TOWER  Similar in concept to a cell-phone tower - A single WiMAX tower can provide coverage to a very large area as big as ~8,000 square km. A WIMAX CLIENT TERMINAL  The terminal receiver and antenna could be a small box or Personal Computer Memory card, or they could be built into a laptop.
  18. 18. WI MAX SYSTEM WIMAX System