SAN FRANCISCO (Business 2.0 Magazine) - Although high-speed wireless networks will enable many new services, voice communication will remain the most important task for most mobile devices. But here, too, change is afoot.

Today wireless data services are treated as applications that run on top of cellular voice networks. But ultimately the reverse will be true: As mobile networks shift to Internet-based protocols, voice will become just another application running on what is essentially a data network.

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In the meantime, many mobile devices will enable consumers to route their voice calls over the most efficient (or inexpensive) network available.

If you get better wireless coverage inside your home with Wi-Fi, for example, conversations can be carried by VOIP. Outside the home, however, your calls will be transferred to a more pervasive cellular network.

The way we communicate will also change as technology highlights the importance of "presence." Presence is simply real-time information about the status of a user. (Think of the "away" message that can be displayed on many instant-messaging systems.) On a mobile device, presence data will become more nuanced to indicate your location, busyness, or even mood.

When advanced networks enable virtually any kind of communication anywhere, presence information will become the most basic way to encourage (or discourage) different kinds of contact.

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Read more about your wireless future:

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• Tomorrow's wireless devices
• Productivity: The everywhere office