PPCS June 2021 Virtual Meeting: A Brief Prehistory of Voice over IP with Steve Casner
PPCS June Meeting - Technical Webinar
A Brief Prehistory of Voice over IP -- with Steve Casner co-recipient of IEEE 2020 Internet Award.
This talk explores the development of interactive voice communication
over packet-switched networks beginning in 1974 with experiments over
the ARPANET -- before IP and the Internet were invented.
To achieve low-delay transmission required changing some fundamental assumptions
about the service provided by the network along with the development
of new network protocols to provide the different functions needed for
real-time communication.
The low (50 kilobit/second) data rate of the ARPANET also required the development of speech compression algorithms
in order to squeeze the packet voice stream through the network.
These elements have evolved over the decades since, but the same
technologies enable our present-day VoIP and teleconferencing services
over the Internet.
One highlight of this talk will be the showing of an entertaining movie shot on film in 1978 to demonstrate a
multi-party teleconference over the packet network.
Date and Time
Location
Hosts
Registration
- Date: 10 Jun 2021
- Time: 06:00 PM to 08:00 PM
- All times are (UTC-06:00) Mountain Time (US & Canada)
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- Colorado Springs, Colorado
- United States
- Starts 30 May 2021 11:00 AM
- Ends 10 June 2021 12:00 AM
- All times are (UTC-06:00) Mountain Time (US & Canada)
- No Admission Charge
Speakers
Stephen L. Casner
Biography:
Stephen L. Casner received his B.A. in Mathematics from Occidental College in 1973 and his M.S. in Computer Science from the University of Southern California in 1976. At USC's Information Sciences Institute, he designed and implemented protocols and software for some of the earliest experiments with packet voice using the ARPANET beginning in 1974. As higher-bandwidth packet satellite and terrestrial networks became operational in the 1980s, he led the project at ISI to develop and deploy video teleconferencing over those networks. That project built a custom, packet-oriented video codec and later developed techniques to allow commercial video codecs designed for circuits to operate over the packet-switched networks.
He served as chairman of the Audio/Video Transport (AVT) working group of the Internet Engineering Task Force (IETF) from its inception in 1992 until 2003. He authored 15 IETF protocol specifications (RFCs), in particular serving as an author and the principal editor of the specification of the Real-time Transport Protocol (RTP) developed by that working group. RTP provides the foundation for media transport in many telephony and video conferencing systems today as well as for other real-time multicast and unicast applications. Its design drew significantly from the Network Voice Protocol and Packet Video Protocol developed in the earlier work at ISI.
Beginning in 1992, he was the primary organizer for the establishment of the worldwide Internet Multicast Backbone (MBONE), an experimental virtual network overlaying the Internet for broadcast of audio and video using multicast Internet Protocol and RTP-based applications. The MBONE enabled live streaming of IETF meetings including return audio from remote participants. It also carried the first Internet “radio” broadcasts.
In 1995, he took this experience to the commercial arena with further development of packet-based audio and video technology for both conferencing and streaming applications at Precept Software, which was then acquired by Cisco Systems in 1998. From 2000 until retiring in 2014 he shifted gears to work on network performance measurement and routing analysis at Packet Design. In retirement he continues to work on software and hardware projects such a volunteer effort for the Computer History Museum to produce an operational emulation of the 1960s-era IBM 1620 computer.
Stephen L. Casner is a lifetime member of ACM. He was awarded the 2011 Leadership Award by the International Multimedia Teleconferencing Consortium and was the co-recipient with Eve M. Schooler of the IEEE 2020 Internet Award.