Microsoft is helping phone companies build a new Internet protocol television system (IPTV) infrastructure for delivering bleeding-edge television services, superfast Internet and phone services over a single line to the home.

Microsoft TV will allow phone companies to deliver four live pictures on a screen at once, with instant channel changes and more options for on-demand video rentals, including high-definition content. It will also merge phone services, so incoming messages, e-mail and caller ID can be displayed on users’ television screens.