oing away as a result of the passage of the Telecommunications Deregulation and Competition Act of 1996. interface A shared boundary or point common to two or more systems across which a specified flow of information passes. If interfaces are carefully specified, it should be possible to plug in, switch on, and operate equipment purchased from different sources. Interface can also refer to a circuit that converts the output of one system or subsystem to a form suitable to the next system or subsystem. interference Unwanted energy received with a signal that scrambles it or otherwise degrades it. interframe coding A compression technique used in video communi- cations in which the redundancies that can be found between successive frames of video information are removed. This type of compression is also referred to as temporal coding. Video Communication: the Whole Picture interlace A technique for "painting" a television monitor in which each video frame is divided into two fields with one field composed of the odd-numbered horizontal scan lines and the other composed of the even- numbered horizontal scan lines. Each field is displayed on an alternating basis-this is called interlacing. It results in very rapid screen refreshment and is done to avoid visual flicker. Interlacing is not used on computer monitors and is not required as part of the US HDTV standard. International Standards A non-treaty standards-making body that, among Organization other things, helped to develop the MPEG and JPEG standards for image compression. See ISO. International One of the specialized agencies of the United Nations Telecommunications that is composed of the telecommunications Union administrations of roughly 113 participating nations. Founded in 1865, it was invented as a telegraphy standards body. It now develops international standards for interconnecting telecommunications equipment across networks. Known as the CCITT until early 1994, the ITU played a big role in developing audiovisual communications standards through its T