History of LPC Digital Speech and its impact on the Internet Protocol

3 July 2006

The following material is intended to supplement the article ``Digital speech and the Internet protocol: the 1974 origins of VoIP,'' to appear in the IEEE Signal Processing Magazine in 2005. Eventually I hope to post an expanded version of that short article here which will include additional detail, more stories, and more references. This information can be found in the pdf slides of talks, the accompanying video, and other relevant links listed below:

• A version of the talk presented to the Computer Club on 29 June 2006, Research Triangle Park, North Carolina, 11 June 2007.
• The original talk California Coding: Early LPC Speech in Santa Barbara, Marina del Rey, and Silicon Valley, 1967-1982 was presented in January 2004 at the Special Workshop in Maui:Lectures by Masters in Speech Processing. The talk describes several threads of the history of LPC speech with an emphasis on Pacific rim contributions. One of the stories is the development of the first packet speech protocols and experiments on the ARPANET, especially the first documented real-time packet speech communication between Lincoln Labs and Culler-Harrison, Inc. in December 1974. The talk includes extensive references to both published and company documentation.
• The updated version for the August 2004 presentation at the University of California, Santa Barbara. The update includes further details regarding the ARPANET and Internet side of the story.
• The MPG video of the 1976 packet speech conference on the ARPANET shown in the talk.
• The official RFC for Specifications for the Network Voice Protocol, NSC Note 68, January 1976.
• For Interenet history with reference to the separation of IP from TCP, see B.M. Leiner, V.S. Cerf, D.D. Clark, R.E. Kahn, L. Kleinrock, D.C. Lynch, J. Postel, L. Kleinrock, D.C. Lynch, J. Postel, L. C. Roberts, S.S. Wolff, ``The past and future history of the Internet,'' Communications of the ACM, Vol. 40, No. 2, 102--108, February 1997. See also http://www.isoc.org/internet-history/
• The Voice over IP Forum. See in particular the "Materials Submitted to the VoIP Forum" link with opinions from Bob Kahn (Corporation for National Research Initiatives) and several polititians, companies, and scientists.

Robert M. Gray