BOSTON - Users had a clear focus at last week's WiMAX World conference: They wanted to know more about cost-effective, reliable, licensed wireless broadband for applications such as backhaul, access to wireline network services and data backup/recovery.

The conference is one of the main events for the WiMAX community, a constellation of chip vendors, radio and equipment builders, billing and management software vendors, systems integrators, carriers and service providers all trying to exploit the IEEE 802.16 standards for wireless broadband. This year's show signed up about 3,000 attendees, compared with just 750 last year, and 150 sponsors and exhibitors.

There was a clear divide between corporate users focused on practical concerns and some vendors, such as Motorola, which sketched visionary scenarios of mobile, "personal broadband" services and devices. Those vendors are focusing on one branch of WiMAX - 802.16e, the developing IEEE standard for mobile wireless broadband, some of it delivered over unlicensed frequencies.

But the most likely corporate services to exploit WiMAX first will be based on licensed spectrum and the fixed WiMAX standard: 802.16-2004, formerly known as 16d. Each base station can deliver up to 75M bit/sec, over a typical range of up to 5 miles.

"The two standards are not the same, and they address very different markets," says Craig Mathias, principal at Farpoint Group, a consultancy specializing in wireless networking. "We see WiMAX dominating for residential and business [wireless] access to the Internet, in fixed, metroscale nets."

It's precisely that scenario of fixed, metro-area access that is drawing the serious attention of users and service providers.

The city of Minneapolis is working toward creating a pervasive wireless mesh network for public safety workers and city employees, and for providing a low-cost, broadband wireless Internet access for residents and businesses.

The all-IP network will likely combine an 802.11-based mesh for client access, with WiMAX providing backhaul, in addition to fiber, says William Beck, the city's deputy CIO.

"Direct connect and backhaul are the plays for WiMAX," Beck says. "We have 350 facilities around the city that we want to connect. We can use WiMAX for that." Such a network would let the city shift mobile computing from expensive Sprint cellular data services and support such bandwidth-hungry applications as its growing web of wireless surveillance cameras.