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 …
January 31st, 2011 at 1:45 am
@TheGeek001 I agree, it is really sad and it’s not even an old video. The first half is without a doubt very interesting but it’s just incomprehensible most of the time. The second half (/talk) starts at 45:20
January 31st, 2011 at 2:19 am
It seems like the audio is just cutting out. It doesn’t go faint as it would when stapping away from the mic, it simply cuts of fthen returns. I think there was just something wrong with the audio equipment.
January 31st, 2011 at 2:37 am
For a high tech company Google records too many of these Tech Talks in such a low tech/ low quality way that makes them nearly useless.
January 31st, 2011 at 3:19 am
With all due respect to Danny, the first half of this video is simply unusable.
Too many times there is an interruption of the lecture flow because he stepped away from the microphone by a step or two, making it impossible to hear him.