Don't hold your breath for "true" broadband wireless services: They'll be based on handheld devices that don't exist yet and networks that have barely been built, according to speakers at the Broadband World Forum in Paris.

While operators have been promoting high-speed data services from their 3G (third-generation) networks, and successor technologies like HSDPA (High Speed Downlink Packet Access), "true" broadband wireless doesn't really exist yet, according to Peter Newcombe, president of Nortel Networks's carrier networks division for Europe, the Middle East and Africa.

True broadband exists when people can't tell whether the content and applications they're using are stored locally in their device or on a far-off server. Fixed-line PC connections, such as ADSL (Asymmetric Digital Subscriber Line) and cable, often give that experience, but the wireless world has still to catch up, according to Newcombe.

"3G doesn't give us true broadband," he said in a panel discussion Wednesday about the future of wireless services.

Of course, Newcombe's views aren't that surprising. Nortel agreed to sell its 3G business last month to Alcatel. Having cornered only a small part of the 3G market, Nortel hopes to build a bigger business selling equipment for 4G (fourth-generation), the next generation of wireless networks.

But Newcombe wasn't the only panelist to suggest that the full wireless experience is yet to come. Nokia believes a new class of devices are needed, designed from the ground up for the wireless Internet, said Ari Virtanen, Nokia vice president for multimedia convergence products.

Smartphones and PDAs (personal digital assistants) will continue to exist, he said, but people will also want products that are more suitable for high-speed wireless services like mobile TV.

He offered as examples Nokia's 770 Internet tablet, which includes a Wi-Fi connection and runs a Linux-based operating system, and the new class of ultramobile PCs, such as Samsung's Q1, which are based on Microsoft software.

Young people see the Internet differently from their parents, driving the need for the new device types, he said. When most adults think of the Internet, they instinctively think of PCs. "When my son thinks of the Internet he thinks about friends, music, movies and games," Virtanen said. "The technology is irrelevant."

So which network technologies will carry the 4G services? Nortel is betting on a combination of three, Newcombe said: WiMax, LTE (long-term evolution, sometimes referred to as 3.9G), and a flavor of CDMA (Code Division Multiple Access) called Ref C. The company's also watching the Next Generation Mobile Networks project, in which several operators are defining requirements for tomorrow's high-speed networks.

Supporting technologies also need to evolve, said Giovanni Colombo, head of long-term research at Telecom Italia. Operators need to make better use of context information, so they know whether a person is in a meeting or free to access a service. And payment services need to be interoperable, and linked to banking systems, for mobile commerce to take off, he said.

Telecom Italia is also experimenting with "combinational services," he said, where two network types might be used simultaneously for the same call. For example, a person's voice could be travelling over the public switched network while a presentation is sent over an IP network.

The mobile Internet today is at the stage that voice telephony was 15 years ago, just before mobile phones took off, Nokia's Virtanen said. "Mobility will be the next major trend in the Internet," he added.