-Fi and VOIP"> Bridging Wi-Fi and VOIP Ive been yearning for an effective bridge between cellular and Wi-Fi-based VOIP phones for years. I want one phone, one number, that works great on a cellular network as I roam around town, and then on my wireless broadband network at home and in the office.Last week at CTIA, though, I got some depressing news from the telcos I talked to. Roaming and billing are the big problems, they claimed, in making my dream reality. Its hard enough to hand off a call from cell-site to cell-site. Adding in Wi-Fi, with the possibility of roaming from access point to access point to cellular, creates a thorny and almost intractable problem. Sigh. I take that sigh back. Here at VON I sat down with LongBoard, which claims to have solved the problem. Their edge device, a telco-installed switch, enables Wi-Fi to VOIP routing. Heres how it works. The companys software runs on your Wi-Fi/cellular phone. When you make a call, it determines which of the available networks are stronger, and uses that network to make the call. The companys box, installed at the telco, routes the call, and communicates using a 1XRTT or GPRS data channel back to the app running on the phone. Between the two of them, they monitor signal strength for both networks, and switch between them when one fades. For example, imagine a call initiated via VOIP on a Wi-Fi network. If it begins to fade, the phone signals the switch, which initiates another connection from switch to phone using the cellular network. The phone ends up with two conference-style connections to the switch. If the Wi-Fi signal fades too far, the phone quickly switches over (within 300 milliseconds) to the cellular connection. Go back in range, and the connection switches again. You cant buy the service today, but a major European wireline telco will be rolling the system out in a series of trials, which will culminate in publicly available service later this year. Here in the U.S., a major hospital is trialing the systembecause cell phones can interfere with certain medical equipment. The trial hospital expects to replace a variety of phones and pagers with a single phone. Billings another problem, but the company claims to have that solved tooby working with large partners like Siemens. Im looking forward to seeing some successful trialsand giving up all these phones and phone numbers for one device that roams with me everywhere. Next page: Intertex Delivers SMB SIP Server.
The phones are finally here. Sony Ericssons lame P900 has built-in Wi-Fi, as does Nokias forthcoming Communicator 9500. The Treo, Samsung i600 and other smartphones could as well, once Sandisk provides SmartPhone 2002 and Palm OS drivers for its SDIO Wi-Fi card.