A Brief Prehistory of Voice over IP parts 1 & 2

Google Tech Talk August 10 & 11, 2010

ABSTRACT

Presented by Danny Cohen and Stephen Casner. This talk explores the development of interactive packet voice beginning in 1974 with experiments over the ARPAnet in the NSC (Network Speech/Secure Communication) program sponsored by ARPA, initiated by Bob Kahn. One highlight will be the showing of a movie made in 1978 to demonstrate a multi-party teleconference over the packet network, including one participant interfaced from a telephone. The talk will be presented in two sessions (two days), with the movie shown at the start of the second session. Part one covers concepts and lessons from this project: * A 1971 realtime distributed flight simulation that sparked the idea * Understanding real-time vs non-real-time communication * Digital speech and the need to compress it (PCM, DPCM, CVSD, LPC/LPC10) * Network Voice Protocol (NVP) over the ARPAnet, type0/type3 packets * The birth of the Internet with TCP * Separating IP from TCP and adding UDP * Building NVP-II on top of IP * Adding packet video (DCT based compression) Part two emphasizes the development of the voice protocols: * Introducing and showing the teleconferencing movie from 1978 * Advances in equipment and function at the end of NSC in 1982 * Progress stalled, waiting to low-cost vocoding * Development of IP Multicast and the MBone * Evolution from NVP to RTP, and RTP design philosophy * Conferencing control protocols * More recent history of VoIP Speaker Info: Danny …