WiMAX vs WiFi

[Kamrul Hasan]

Basically difference between WiMAX and WiFi are distance, speed, cost, and so on.
WiMAX coverage area about 30 miles (50 km) and WiFi coverage area about 10 km.

WiMax (802.16) is is a newer standard of wireless networking designed to provide the last mile of high speed internet access to the end user. Some people would call Wimax WiFi on steroids but this would be to broad of an assessment. Wifi was and still will be used in LAN environments for the foreseeable future. WiMax was designed to provide (MAN) Metropolitan Area Access, to homes and businesses.

WiMax base stations will have the ability to provide approximately 60 businesses with T1 access and hundreds of homes with DSL/Cable speed access…in theory. Engineers are stating that WiMax has the capability of reaching 30 Miles but real world testing has shown 4-8 mile working radius.

WiMax (MAN) deployments are similar to a WiFi network. First the ISP would have their T3 or higher access. The ISP would then use line of sight antennas (Bridges) to connect to towers that would distribute the non line of sight signal to (MAN) residential/business clients.

WiMax line of sight antennas operate at a higher Frequency up to 60mhz. Distribution antennas do not have to be in the line of sight with their clients. Non – line of sight towers operate on a range similar to WiFi . WiMax can operate right next to cell phone towers with no interference.

WiMax networks are similar to Wifi in deployment. The Wimax Base station/Tower will beam a signal to a WiMax Receiver. Similar to a WiFi access point sending a signal to a laptop. As far as I can tell laptops will be shipping with Wimax receivers in 2006.

QOS (Quality of Service) is an major issue with WiMax because of the number of people accessing a tower at once. Some would think that a tower could be easily overloaded with a lot of people accessing it at once. Built into the WiMax standard is an algorithm that when the tower/base station is nearing capacity then it automatically will transfer the user to another WiMax tower or cell. Unlike a Wifi clients who have to kind of fight to stay associated with a given access point; WiMax will only have to perform this hand shake at the MAC level the first time they access the network.

[Robert Syputa]

Sorry fror the late reply: WiFi is useful and cheap ... excellent for low to teh ground service providers. But that does not make it a unified communications network that can scale up as well as down.

Wireless has made attempts, with its success being a major obstacle, to become UMTS, a unified approach to wireless communications. Success led to stratification of technology, IPR and market development. WiMAX came along that amplifies the open development of WiFi into the managed, scalable network and enterprise class mobile applications and cloud 4G/computing environment. Due to its own need for change and pressure from the implosion of IT and broadcast industries, the mobile industry has changed.

The 3G industry is like all huge, well capitalized, mature industries: they become assimilators of technology and business methods. However they distort the innovation, they mass perpetuates motion.

[Alan J Weissberger]

Robert, Thanks for providing such a clear explanation of why there is no business case for operator provided or municipality provided WiFi. However, I hear some WISPs still use WiFi for broadband wireless Internet access. The one's I've talked to wanted to go with WiMAX but they couldn't obtain licensed spectrum. Perhaps, the 3.65GHz lightly licensed regime will cause them to shift from WiFi and proprietary BWA to fixed WiMAX.

[Robert Syputa]

WiFi has been knocked down from two directions:

1) There is not a business case for an operator deployed service. User deployed services have failed because of spotty, unreliable service caused by the simple fact that the few subsidize use by the many. While some networks are supported by some people some of the time, the free-net access model has failed.
2) The business case for Muni-fi, municipal WiFi city-wide projects has failed due to difficulty to achieve coverage, cost of deploying and managing WiFi MESH networks, and insufficient revenue.
For example, the WiFi MESH programs in San Francisco, Philadelphia, and other major cities ended because the actual costs of deployment to reach the coverage and building penetration proved to be 3X-4X more than original estimates.
We (Maravedis) had discussed this in our reports prior to attempts to deploy in Philly and similar cities. Our advice had been that multiple revenue sources were needed to make a sustainable business case.
WiFi has use of free spectrum - while 'free' comes at the cost of interference, short range and shared access.

WiMAX is available in multiple spectrum for which business case can be built.

[Alan J Weissberger]

Does anyone still think that long haul/mesh WiFi can compete with WiMAX (either 802.16d or e) for metro based broadband fixed wireless access?

Has WiFi (including 802.11n) succeeded as an enterprise wide technology, e.g. replacing 10/100 Base T to the desktop?

If not, it seems the main applications for WiFi are home networking and Internet access via hot spots.