When the hype surrounding a new technology becomes especially boisterous, it seems to take on a life of its own, ballooning to the point where it actually becomes separate from the technology that spawned it. The hype keeps growing and floats up to the ceiling of the room, where we all point and gawk at it and laugh at the absurdity of it, until someone finds a long sharp stick to jab at it. Then it pops.

What's left at floor level is the technology itself and an understanding of the real applications for which it can be used. It may still be too early to say whether or not the largest carriers in the U.S. will deploy WiMAX and if so, what for, but we can probably assume that in most urban and suburban markets in the U.S., WiMAX will not replace existing broadband services like DSL or cable modem being offered by those carriers.

But there are a wealth of applications that both certified Fixed WiMAX and WiMAX-like equipment already are being used for, and many of them will help WiMAX create niches all its own within the greater broadband market.

One of the application scenarios in which Fixed WiMAX is excelling is in communities that don't have other broadband services options. This includes rural markets, remote “ex-urb” consumers (former urban dwellers who have moved out to the country) and customers in developing countries that are greenfields for broadband services.

In mature broadband markets, such as the U.S., WiMAX may be part of a second-phase strategy for some carriers that have already pushed DSL or cable as far as those technologies allow. “Fixed operators in the U.S. want to reach out into some of the communities that they couldn't reach before, when they first started deploying broadband,” said Prashant Pai, director of broadband technology for Siemens.

“Fixed WiMAX for rural broadband is really a go at this point, and it doesn't matter where you are — in the U.S., Canada, Europe,” said Mark Whitton, vice president and general manager of WiMAX and wireless mesh networks for Nortel Networks. “In many of those cases, WiMAX is the only option, so service providers don't have to discount to get into the market, and they don't charge a premium either. Because of that, once you have a subscriber, you have them for a while. You can sign them up for a year or two, and it helps you meet your business model.”

Whitton said those ex-urbs also may hold a key to the success of WiMAX in rural markets because they usually have a lot of disposable income and also don't want to lose the broadband capabilities that were available to them in the city.

Nortel recently showed how Fixed WiMAX could be used to meet rural needs in a deployment that it carried out for ISP Netago Wireless and the Alberta Special Areas Board municipal body in an 8000-square-mile area of rural Alberta. That area has a total population of about 12,000 people, but at least 5000 of them live outside of the reach of DSL, amid inhospitable terrain, Whitton said. With Fixed WiMAX, Netago has been able to deliver an average of 1 Mb/s to 3 Mb/s to each customer.

Another area in which Fixed WiMAX-like solutions are making an impression is public safety. As an example, Alvarion and IBM recently announced a new public-safety network deployment in Fresno, Calif., that is allowing police officers to send and receive text messages, still images and even full-motion video over a 900 MHz network using mobile data terminals and their hand-held personal digital assistants (PDAs) located in their vehicles.

The officers use the IBM WebSphere Everyplace Connection Manager to access the system. That software allows government-grade wireless encryption, roaming and compression to the city's 250 police vehicle fleet.

Backhaul of wireless networks also has been long considered a top potential application for Fixed WiMAX. However, backhaul is a topic on which the industry carefully needs to separate WiMAX hype from WiMAX reality. Initial projections for the technology forecasted bandwidth of up to 70 Mb/s, but most field trials and experiences of the last few years have shown the realistic bandwidth ceiling for a single end point is much lower, around 2 Mb/s in some cases. Officials at Nextlink, a service provider using higher-frequency, non-WiMAX technology to support its backhaul business model, recently said the mobile 3G network sites require an average of 30 Mb/s backhaul capacity, so it doesn't appear WiMAX can do the job, at least where bandwidth-rich 3G multimedia networks are concerned.

“Backhaul is a niche application, where WiMAX allows you to aggregate bandwidth from a number of lower-bandwidth cell sites,” said Siemens' Pai. It comes down to radio frequency planning — if you have just 10 MHz of spectrum, is it worthwhile to try to use that to backhaul 30 megabytes of data when T-1 connectivity can do that job? People who want to do it are looking at it strictly from an opex savings point of view.”

Pai, like Nortel's Whitton, has a lot of confidence in Fixed WiMAX as an access technology. “Right now, it's all for voice and data. VoIP is like a given in any Fixed WiMAX deployment,” Pai said. “Video, we haven't seen yet because a lot of the bandwidth is being used for other applications, and you would need to create a separate video channel. Spectrum becomes the limiting factor where video is concerned.”

Still Sudeep Gupta, director of marketing strategy for broadband wireless access at Alcatel, one of the vendors putting more of its energy into Mobile WiMAX solutions, said that Fixed WiMAX will remain mostly an outdoor technology, as it often can't deliver sufficient indoor penetration for many residential and office applications.

Mobile WiMAX, which will not enter the WiMAX Forum's interoperability certification until late this year — and may not be broadly commercially deployed for another two years — delivers richer applications experience through the use of multiple input/multiple output (MIMO) and other technologies to enhance bandwidth. Other solutions to be used with Mobile WiMAX, including beam-forming, will improve coverage.

Gupta said the richer, untethered usage experience that customers get from Mobile WiMAX, unlike what they would get from Fixed WiMAX, will rate premium pricing. “Our studies have shown that when you add mobility to the equation, users are willing to pay up to three times more for a particular service over when it is delivered in a fixed environment,” he said. “As for the killer application, the market is often surprised at what becomes a hit, but usually it provides a personalizing experience for the subscriber.”

Whitton added, “I don't think there's a killer app for Mobile WiMAX. It will be a killer experience. A year ago people were saying ‘Internet anywhere’ was the big application. Now, video is becoming more prominent, and if you're worried about the amount of throughput you'll need, MIMO will help deliver that kind of capacity.”

Gupta said having a personal video experience could be an application that helps Mobile WiMAX earn its deployment, but that it won't necessarily be a technology that provides broadband to residences for applications like IPTV. “Video is definitely a targeted application for WiMAX, although IPTV is not. WiMAX offers DSL-like speeds in a mobile environment, and true IPTV requires 20 Mb/s to 25 Mb/s,” he said. “However, for a service provider that has enough spectrum, they could deliver mobile TV-IP-based video, but with a resolution that is more appropriate for a mobile device.

“That's not to say that WiMAX can't play a part with IPTV. WiMAX can complement IPTV to provide users with a way to extend their IPTV experience. For example, suppose the subscriber is watching a program on their 50-inch plasma TV, but they have to leave. They could pick up a Universal WiMAX [the name Alcatel uses for Mobile WiMAX] portable device, hit a key, and the video stops playing on their TV and shifts seamlessly, so they can walk out the door.”

Although Fixed WiMAX and similar fixed wireless technologies are already delivering broadband access for niche applications like rural deployments and backhaul, timing is of the essence for both the early real-world success of Fixed WiMAX and the future potential of Mobile WiMAX. Siemens' Pai said that applications are a function of user need and which technology is deployed and when to deliver them depends on the urgency of that need. WiMAX likely will evolve from a fixed experience now, to a portable one, with the help of laptop-ready technology, to a truly mobile one with the arrival of Mobile WiMAX.

“It's a timing issue,” Pai said. “802.16e is something we'll see in two years, and that's what you really should use for a low-latency application when it's available. But if you have a large chunk of spectrum ready right now and you can't wait for a couple of years, as an operator, you have to ask yourself what your customers need and how soon.