03-08-2012, 12:15 PM
Seminar on Wi-Fi vs. WiMAX
1Wi-Fi vs. WiMAX.pdf (Size: 178.31 KB / Downloads: 104)
WiMAX is not a technology, but rather a certification mark, or 'stamp of approval' given to equipment that meets certain conformity and interoperability tests for the IEEE 802.16 family of standards. A similar confusion surrounds the term Wi-Fi, which like WiMAX, is a certification mark for equipment based on a different set of IEEE standards from the 802.11 working group for wireless local area networks (WLAN). Neither WiMAX, nor Wi-Fi is a technology but their names have been adopted in popular usage to denote the technologies behind them. This is likely due to the difficulty of using terms like 'IEEE 802.16' in common speech and writing.
Uses of Wi-Fi vs. the uses of WiMAX
Wi-Fi is mostly used to provide a Wi-Fi enabled device such as a computer, cell phone or PDA an Internet/LAN connection when in proximity of an access point. Wi-Fi can also be used to create a mesh network. Wi-Fi also allows connectivity in peer-to-peer mode, which enables devices to connect directly with each other.
WiMAX on the other hand with its higher bandwidth and longer reach is planned to be used for connecting Wi-Fi hotspots with each other and to other parts of the Internet, providing a wireless alternative to cable and DSL for last mile (last km) broadband access, providing high-speed mobile data and telecommunications services (4G).
Capacity of Wi-Fi vs. WiMAX
Both the Wi-Fi and the WiMAX connectivity are dependent on the distance of two connection points (antennas). Keeping this in mind we can see that when using Wi-Fi with the IEEE 802.11g standard, which is the most common standard used on today’s equipment, the data rate is around 54 Mbit/s and the range indoors are around 30 meters. This range and data rate is changed with the conditions of the area used and the line of sight of devices used.
WiMAX will deliver 70 Mbit/s, 112 kilometers in theory. But these numbers will change according to conditions, expected values are 10Mbit/s in a 2 KM area.
Advantages and Disadvantages of the two standards
The WiMAX specification provides symmetrical bandwidth over many kilometers and range with stronger encryption (TDES or AES) and typically less interference. Wi-Fi is short range (approximately 10's of meters) has WEP or WPA encryption and suffers from interference as in metropolitan areas where there are many users.
Wi-Fi Hotspots are typically backhauled over ADSL in most coffee shops therefore Wi-Fi access is typically highly contended and has poor upload speeds between the router and the internet.
It provides connectivity between network endpoints without the need for direct line of sight in favourable circumstances. The non-line-of-sight propagation (NLOS) performance requires the .16d or .16e revisions, since the lower frequencies are needed. It relies upon multi-path signals, somewhat in the manner of 802.11n.
One disadvantage of WiMAX is the spectral limitation, in other words limitation of wireless bandwidth. For use in high density areas, it is possible that the bandwidth may not be sufficient to cater to the needs of a large clientele, driving the costs high.
A disadvantage of WiMax over Wi-Fi is that, where with Wi-Fi anyone can set up a wireless network for free, not everyone can set up a WiMax wireless network; and one must pay incredibly huge amounts of money to be given the right to set up a WiMax wireless network in a region. This is because the frequency used by the WiMAX standard is licensed by the governments.