MBone, a set of multimedia communication software tools, was used as the Internet multicast vehicle. The courses were observed throughout the world during the test period (June 9, 1997 to August 1, 1997).
Four ITV courses were chosen for use in the MBone trial. They are all one-term courses, which consist normally of three hours of lectures a week over a twelve week term. The courses that were multicast were chosen on the basis of the interest of their contents to a wide audience, their production values, the extent of electronically accessible support material, and willingness of the instructors to develop web-based support information as part of the experiment. They also had to be recorded in their entireties so that no live sessions, or significant updating, would be required.
The courses multicast were:
Figure 1. Prof. Juan Salinas and Prof. Don Westwood.
Figure 2. Prof. Warren Thorngate.
Figure 3. Prof. Ann Laubstein.
The pre-recorded courses were played back in the television studios of Carleton University Television, located in Southam Hall, where they were modulated onto a spare channel on the Carleton University cable TV system. The modulated signals were carried by coaxial cable to the TeleLearning Research Laboratory, located in the Department of Systems and Computer Engineering in the Mackenzie Engineering Building.
In the TeleLearning Research Laboratory the signals were demodulated. The demodulated composite signal was presented to a PC-based titling card where appropriate information was inserted into the image. The information included the course title, the origination source, and contact information. The titler was programmed to provide the information periodically, both statically and in a roll-over mode.
The composite output of the titler was presented to the SunVideo card in a SPARCStation 20M, equipped with dual HyperSPARC processors. The MBone software was run on the SPARCStation, which is connected to the Systems and Computer Engineering LAN (.sce). The IP multicast packets on .sce were tunneled back through the SPARCStation FORE Systems ATM card, to a Newbridge 36150 ATM switch, which comprises the TeleLearning Research Laboratory's dual DS3 fibre optic connection to OCRInet.
An IP tunnel was provided through one of the OCRInet switches to the CANARIE National Test Network (NTN), through which they were distributed to the provincial research networks across Canada, and to international Internet gateways.
Although the OCRInet-NTN connection allowed us to use the full 500 kbps allowance for IP multicasting, the courses were multicast at a rate of 128 kbps to make sure that local or regional bandwidth capacity was not exceeded. Thus, a 128-kilobit per second video stream (typically 1- 4 frames per second) was used.
Multicast is used because it provides one-to-many and many-to-many network delivery services for applications such as video-conferencing and audio that need to communicate with several other hosts simultaneously. MBone is currently used for hosting public events, workshops, seminars, classroom courses, IETF meetings, private meetings that span multiple continents and organizations, news, and entertainment events.
The MBone is a technology that enables distribution of, and access to, real-time
interactive multimedia on the Internet. "MBone" stands for the IP-multicast Backbone on the Internet. MBone uses the IP-multicast routing schemes to achieve fast, real-time, multiparty communication in an efficient manner. Originally, a set of UNIX-based software tools were implemented to study applications which could be used over the Internet, primarily between workstations. More recently, the tools have been developed for use on personal computer terminals.
Before one can use MBone, a multicast session must be started by using the session directory tool, sdr. sdr allows a session to be advertised, and provides information about it. The video tool, vic, provides live MBone video. It is accessed though sdr. The audio tool, vat, provides live audio It provides viewers with a list of all of the participants in the session. vat also identifies who is speaking at any given time by highlighting their listing. The whiteboard tool, wb, is a clipboard-like document-sharing application that allows one or more sites to share documents in real time. MPOLL is an opinion polling and rating collection tool. It allows viewers to submit their respond to short yes-no questions in real time.
Figure 4 sdr and Session Information tools
Figure 5 vic tool and expanded video image
Figure 6 vat (Visual Audio Tool) and MPOLL tool
Figure 7 MBone tools - usual screen display
For more details about the MBone, please refer to the book called MBone: Interactive Multimedia On The Internet by Vinay Kumar. (www.MBone.com/MBone/references.html)
Education) is a nonprofit corporation established on March 5, 1993. It evolved from the efforts of more than 200 people from 56 organizations representing Canada's research, university, business and government communities. Their efforts, over a four year period, developed a seven year multi-phase Business Plan which defined a program to improve Canada's overall competitiveness in the Information Age. CANARIE has over 140 private and public sector, fee-paying members. It has a twenty-one member Board with ten members representing the private sector and ten representing institutions, with the twenty-first being jointly appointed.
The mission of CANARIE is to facilitate the development of critical aspects of the communications infrastructure of a knowledge-based society and economy in Canada, and in so doing to contribute to Canadian competitiveness in all sectors of the economy, to wealth and job creation and to our quality of life.
CANARIE's National Test Network (NTN) is the world's largest high speed test network spanning 6,000 km from St. John's, Newfoundland to Vancouver, British Columbia, interconnecting 11 smaller high speed test networks across Canada. The NTN provides both high speed DS3/OC3 (45 Mbps/155 Mbps) Internet (TCP/IP) and Asynchronous Transfer Mode (ATM) connectivity. In addition, the NTN has high speed connectivity to Europe provided by Teleglobe and ATM satellite connectivity provided by Telesat Canada. Connections to the United States are presently being deployed by Unitel to similar test bed initiatives across the country.
The NTN is intended to support CANARIE's mandate to accelerate the development of advanced networking applications in Canada and was built in partnership with Canada's major telecommunications carriers Bell Canada, a member of the Stentor Alliance, and Unitel.
The NTN is available to researchers and developers in areas such as business, education and health care to test and develop new high speed broadband applications. These applications can range from pre-competitive research and development to commercial trials of new business applications. Furthermore, the NTN is available to carriers and their customers to test and evaluate high speed broadband applications and connectivity as an enhancement to their commercial broadband offerings. Typical tests and applications include multimedia distance education trials, medical imaging and advanced video conferencing solutions. Businesses and universities are using the NTN to test new and advanced Internet applications such as virtual reality, high speed World Wide Web services and real time audio and video.
not-for-profit organization which has developed from an initiative of the Ottawa Carleton
Research Institute (OCRI). It was formed on November 17, 1993 and commenced regular
network operations on January 23, 1994. It is a partnership between industry, government and post-secondary institutions, and includes service and equipment providers as well as the user community.
The founding partner groups of OCRInet Inc. are:
The mission of the OCRInet is
These are viewers from June 2/97 to August 1/97.
June 2/97 Trent MacDougall (Dalhousie)
June 6/97 Andrew Patrick (via CANARIE)
June 12/97 Bill St. Arnaud
June 13/97 Tim Clinton (Culture Net) email: clinton@Cnet.ffa.ucalgary
June 16/97 Bill St. Arnaud
June 17/97 Bill St. Arnaud
Hiroaki Ikeda (Chiba University)
Stefan Lundberg (GD Data Centre)
Academic Users Support (University of Oregon)
Yves Lepage (McGill University)
Marc Hasson (Mentat) email:firstname.lastname@example.org
Hans Kuhn (email:email@example.com)
June 18/97 Rob Murray (email:firstname.lastname@example.org)
Loris Marchetti (CSELT) email: email@example.com
Bill St. Arnaud
Nicole Carter (email: firstname.lastname@example.org)
Rimen Wong (Honk Kong Star Internet Ltd.)
Charles Ray (CEWES)
John Dundas (Caltech)
Andrew Patrick (via CANARIE)
Russel Doyen (Sailor Project)
Rob Ballantyne (SFU)
June 19/97 Rene
Bill St. Arnaud
Marty Hoag (NDSU ITS) email:email@example.com
Service D'Enseignement a Distance (CNAM)
Particular (Particular) email:firstname.lastname@example.org
Malcolm Toms (Faculty of Arts-SFU )
June 20/97 Francisco Cruz (uc3M, Madrid)
Hermann Kuhn (GKSS Research) email:email@example.com
Martha Harden (email:firstname.lastname@example.org)
Rimen Wong (Honk Kong Star Internet Ltd.)
Regis Bossut (ISEN Lille, France) email:email@example.com
Lucy Lynch (University of Oregon) email:firstname.lastname@example.org
Sam Segler (Fermilab)
Jens Tanneberger (email:email@example.com)
Irene Greif (Lotus Development) email:firstname.lastname@example.org
Christian Asam (email:Christian.Asam@heim8.tu.clausthal.de)
Lotus (Lotus) email:email@example.com
Kim Dimick (Precept Software, inc)
June 23/97 Phil Dax (ENST) email:firstname.lastname@example.org
Bruce Hudson (email:email@example.com)
June 24/97 Bill St. Arnaud
Bruce Hudson (email:Bruce.Hudson@Dal.ca)
July 7/97 CRC-BADLAB-sgi
July 8/97 Bill St. Arnaud
July 11/97 A. Rosselet (email: firstname.lastname@example.org)
Allan Rosselet (U of T as Scarborough) email:Rossolet@scar.utoronto.ca
July 17/97 Mark Allman (NASA LeRC)
Ed May (ANL-HEP) email:email@example.com
Edward Sommer (internet & New Media)
Stuart Levy (Geometry Centre, Uminn)
July 18/97 Davy Chan (CSD- HKUST) email:firstname.lastname@example.org
C. Gondrand (email:chris@isnIos5.in2p3.fr)
Hiroaki Ikeda (email:email@example.com)
Angela Schuett (UCB)
July 22/97 Russ Miller (ORNL)
Ed May (ANL-HEP) email:firstname.lastname@example.org
July 23/97 Roy Turner (Umaine, USA)
R.P.C Rodgers (U.S Nat.Lib.Of.Med)
U. gerlach (email:email@example.com)
July 25/97 Frederic Bouchy (Dyade)
July 28/97 Phil Pishioneri (Cornell Theory Center) email:firstname.lastname@example.org
Simon Leinen (Switch) email:email@example.com
C Gondrand (email:firstname.lastname@example.org)
Saizo Hirose (email:email@example.com)
July 30/97 Ed Golden (SAIC) email:firstname.lastname@example.org
Rafael Cabeza (UPNA)
July 31/97 Olivier DURANT (Ipnhe) email:email@example.com
John Horton (email:firstname.lastname@example.org)
Mark Leber (CEWES) email:email@example.com)
Mat Berkemeier (Boston University) email:firstname.lastname@example.org
Claudio Catania (Hawlett Packard Laboratory) email:email@example.com
August 1/97 Alan Rosselet (U of T at Scarborough)
Herman Kuhn from Denmark wrote that "the quality of audio and video signals was quite good and completely sufficient to perceive the content of the lecture". Loris Marchetti from Italy wrote "the video quality was very good. I don't receive any audio". The latter comment was made before the IP Time To Live was set to 127 from 63.
MBone multicast of lectures that have been designed for television broadcast leaves a lot to be desired. The MBone images are small; they have low spatial resolution, and low frame rates. They are also compressed for transmission, and constant throughput is never guaranteed. So, the MBone image sizes, compression fidelity, frame rates, together with the marginal quality of service demand that special attention be paid to the preparation of graphical material even if careful attention has been paid to the graphics from a television point-of-view. Since some of the information may be lost during transmission, high quality of the original material is required. Lecturers should make sure to make slides, overheads, and blackboard writing carefully, with large font sizes.
Some of the disadvantages for the use of MBone are:
However, the advantages for the use of MBone are:
First of all, the authors would like to acknowledge the initiative, foresight and ability "to get things done" of David Sutherland, who was the Director of Computing and Communications Services at Carleton University at the time the experiment was originated. He, together with Bill St. Arnaud of CANARIE, were responsible for Carleton's participation in the NTN program.
The experiment was carried out under a research contract from CANARIE. It also received support from Project 6.1.4 (Workplace Training over Broadband Networks) of the TeleLearning Research Network, a federal Network of Centres of Excellence. The use of the facilities of the TeleLearning Research Laboratory of the Department of Systems and Computer Engineering, especially their video-equipped workstations, and membership in OCRInet, were essential parts of the experiment. The use of OCRInet to provide broadband ATM connection to the National Test Network was also a vital part of the experiment.
The authors would like to acknowledge the contribution of those who
provided the content for the multicasts. They include the instructors in
the courses that were multicast: Juan Salinas and Don Westwood, Warren
Thorngate, Robert Dick, and Ann Laubstein who made their courses available
for the experiment; the "impresario" of ITV, Robin Allardyce, who single-handedly
arranges for the ITV courses and instructors, and administers the ITV program;
the Director of Carleton University Television, Ross Mutton, who arranged
for the courses to be transmitted on schedule across the campus to the
TeleLearning Laboratory; and Prof. Tim Pychyl of the Department of Psychology,
who co-ordinated the supporting web page developments.