4:30 PM -- Check out this blog entry on a potentially huge issue facing standards bodies, vendors, and carriers as they start to roll out more different types of devices on 3G, WiMax, 4G, and other wireless networks. There's no single standard for locating and identifying portable PCs, MP3 players, digital cameras, digital video recorders, PC cards, and the rest.

Currently, cellular networks do all this behind-the-scenes voodoo using the handset's phone number. But what if you're using a multimedia player that doesn't have a number?

"PCs have media access control (MAC) addresses, MP3 players have serial numbers, other devices may have some other unique semantic ID specific to a manufacturing practice or perhaps even an application service married to a dedicated device," writes Jonathan Spinney. "In tomorrow’s converged 4G world, the lack of a uniform user-ID common to all devices requires rewriting or inventing new Location API standards to support holistic service experiences that run across multiple devices."

It's all a bit technical, but what he's basically saying is that as things stand you can buy a ringtone or MP3 using your phone, but future networks -- on paper at least -- aren't smart enough to let you listen to it using your wireless MP3 player.

Reston, we have a problem...

— Dan Jones, Site Editor, Unstrung