A recent survey of more than 250 subscribers to Webtorials, an educational Web site about networking technologies, revealed some interesting perceptions about broadband mobile network alternatives.

About half the respondents represented enterprise IT personnel and about half worked in service provider companies. Survey takers responded from around the globe, though about half were in North America. A “free association” portion of the survey asked respondents to define as best they could the terms “WiMax” and “4G.”

A good chunk of both groups (about 25 percent) chose “WiMax” as the term they associate most closely with the definition of “4G.” However, the reverse wasn’t true. When asked to define “WiMax,” most respondents chose “mobile broadband” as the closest definition (not “4G”). What’s the difference?


This mysterious term generally refers to “the next generation of cellular” network that will follow 3G, which is being rolled out in pockets all over the world today.

While true 3G technology has specific worldwide industry standards associated with it, 4G doesn’t mandate specific technical network standards beyond the use of the IP protocol and packet-switching technology. Rather, it describes capabilities desirable in the next generation of mobile networks. For example, 4G networks — regardless of how they are constructed — will support IP multimedia applications and the ability for users to roam across dissimilar network infrastructures.


Unlike 4G, WiMax is a set of technical standards for a specific network. Mobile WiMax, which is technically the IEEE’s set of 802.16-2005 standards, will likely be the first available 4G alternative. But the terms aren’t synonymous: Mobile WiMax will be a type of 4G network, but not all 4G networks will be mobile WiMax networks. Just like all vegans are vegetarians, but not all vegetarians are vegans.

What's in a name?

“WiMAX” is a nickname for “Worldwide Interoperability for Microwave Access,” a description that is rarely used anymore. What’s relevant about the name, though, is the “worldwide interoperability” part—a characteristic that has long eluded global mobile networks, particularly since the US split off into two distinct 3G technology camps in the early 1990s.

While there is much debate over whether WiMax continues to be overhyped relative to its potential, many of the enterprise IT managers I talk to tell me their hope is that mobile WiMax will become a single worldwide protocol that works across different carriers’ networks and devices. They are tired, they say, of the fragmentation their users experience as they roam from country to country.

This desire is potentially reflected in the Webtorials survey. Respondents ranked VoIP as the No. 1 application driving their interest in WiMax.

This seems odd, given that there are so many ways to make a phone call in existence today. On the other hand, while global voice harmony is easier to achieve with tri- and quad-band GSM phones, perhaps these folks are seeking one broadband mobile connection that handles all their voice, data, and video needs — and works consistently around the world.

As I’ve frequently mentioned in this newsletter, US carriers today require you to use cellular voice networks to make phone calls and cellular data networks (a separate subscription) for data requirements. VoIP is technically data, but some carriers block it on their data networks, because it competes with cellular voice minutes and revenue.

Can mobile WiMax replace cellular? Whether mobile WiMax will be the magic bullet that delivers global mobile interoperability remains to be seen. Sprint Nextel has said it intends to cover 100 million people in the US with mobile WiMax services by late 2008. The technology is in trials in the UK, Italy and Japan, and services have been available for nearly a year in Korea under the “WiBro” service name.

It’s unlikely that the traditional cellular carriers will simply discard their substantial investments in 3G licenses and infrastructure and start all over with WiMax. Even Sprint continues to invest in its CDMA-based EV-DO network infrastructure. For the short term, anyway, mobile WiMax will likely be a complement to cellular services and will be accessed by client devices with 3G, Wi-Fi, and mobile WiMAX radio connections bundled in.