Stung by criticism of high-cost, flaky service and pandering to recreational Web surfers, cities can justify their investment in free wireless service by using the networks to support public safety radio traffic, attract new businesses and abolish the "digital divide" that can stop low-income workers from landing Internet-age jobs. That's the message from government technology workers gathered at the MuniWireless 2007 conference in Newton, Mass.

Ubiquitous wireless coverage could also improve residents' lives by offering automated traffic monitoring, parking enforcement and meter reading, they said.

But sometimes even those goals fail to sustain public support when a network hits surprise hurdles, said Bill Oates, chief information officer for Boston. The city had been running its new Wi-Fi network for a month in the blocks surrounding City Hall when citizens began to complain that the Internet service provider used a content filter that blocked certain websites.

"We will keep hitting bumps in the road, we know that. But sometimes it makes you ask if it's WiMax versus Wi-Fi versus 'Why even try?'" Oates said Tuesday in a conference session.

Cities can also face a challenge when the local historical society complains that wireless antennas can harm the architectural appearance of city buildings.

City workers in Malden, Mass., found a way around that problem by fitting a Wi-Fi antenna inside the storefront sign of a local bar. The business owner was happy to donate the location in exchange for a strong signal, and the new node boosted coverage in a heavily populated part of town, said Anthony Rodrigues, the city's director of information technology.

That example illustrates that the politics of launching a wireless network can be a tougher challenge than the technology, Rodrigues said. It is fairly easy to link the networks in neighboring towns to share coverage areas or fire response, but much harder to persuade elected leaders to talk about funding the effort or agreeing who will control the network.

The political hurdle applies far beyond the borders of New England, where the conference is taking place, said Esme Vos, the founder of MuniWireless.com, a blog and sponsor of the conference.

Until recently, public wireless networks have existed only in major cities with large budgets, including Philadelphia, Chicago, Houston, and Portland, Ore., she said. But across the United States, the number of municipalities with planned or deployed public broadband networks has risen from 122 in July 2005 to 385 in May 2007, according to MuniWireless.