In a typical scenario, one person places a regular voice call to another person and once it's connected, they hit the camera button on the phone to start a video session. The person on the other end can begin viewing the live video stream once they accept an invitation from the other caller.
Cingular last year began upgrading its existing network based on the Universal Mobile Telephone System, or UMTS, to technology that uses High Speed Downlink Packet Access, or HSDPA. With the upgrade, customers can access Cingular's Broadband Connect high-speed data service, which promises connections between 400 Kbps and 700 Kbps--good enough for browsing the Web or downloading multimedia files such as video and music on mobile devices. Meanwhile, UMTS offers slower speeds between 150 Kbps and 250 Kbps.
The new service will work on Cingular's UMTS/HSPDA network, which means the person making the call and the person receiving it will need a 3G Video-Share phone, such as LG Electronics' CU500v. The two people also will have to have 3G coverage, which still isn't available in all areas. Customers will have to deal with spotty coverage until Cingular and the other carriers further build out their 3G networks.
Different network technologies have emerged to support initiatives like Cingular's. The one used by most of the major service providers is called IP Multimedia Subsystem, or IMS. The service providers are putting IMS in their infrastructures to enable cellular, Wi-Fi, and wireline networks to talk to one another. Cingular says it recently deployed IMS to make video calling possible.
Cingular expects to commercially launch the service by this summer.