Energy aims sights on ATM
- By William Jackson
- Jan 12, 1998
The Multipoint, Gateway and Control-100 unit from Accord Video Telecommunications Inc.
of Atlanta does proprietary transcoding that lets sites with different equipment and
algorithms connect at their optimal speeds rather than at the rate of the lowest common
The MGC-100 supports international H.320 video telephony standards and eventually will
support the H.310 standard for ATM videoconferencing.
"Our strategic goal is to move video to ATM, so this box fits perfectly,"
said Stan Kluz, an ESnet manager at Lawrence Berkeley National Laboratory.
Kluz said he expects to put the MCU into production this month and hopes to begin
testing the ATM interface by spring. No timetable has been set for moving video to the ATM
network, but "it won't happen overnight," he said.
DOE's Office of Energy Research uses ESnet to link its laboratories and university
research facilities. Begun as a T1 network in 1989, ESnet today directly connects 30 sites
to the backbone at speeds up to 155 megabits/sec.
Through Federal Interagency Exchange and Metropolitan Area Exchange points, ESnet also
links to Defense Department and NASA networks as well as the Internet and many regional
Every month ESnet handles about 400 videoconferences totaling about 1,600 hours via
dial-up ISDN circuits and a video server from PictureTel Corp. of Danvers, Mass., Kluz
Conferences take place on meeting room and desktop conferencing systems at 64
kilobits/sec to 1.5-megabit/sec T1 speeds. Typical conferences use 128 kilobits/sec to 385
kilobits/sec of bandwidth.
The change to Accord's MGC-100 videoconferencing platform will bring advantages even
before an ATM interface is available, Kluz said.
The box can scale from eight to 1,280 ports and uses hot-swappable cards and redundant
"It's an almost bullet-proof design," Kluz said.
The box recognizes and translates video bit rates, frame and resolution rates, audio
compression and interfaces for each conference site.
Sites with different equipment can transmit at their optimal speeds. The MGC-100 shows
up to nine images on a screen at once.
Initial ESnet tests linked two sites on an ATM backbone at 384 kilobits/sec, two sites
on a circuit-switched network at 384 kilobits/sec and one audio-only site.
ESnet's Web interface lets users with scheduling privileges log onto the Web site and
set up videoconferences. Kluz said adapting the ESnet scheduling system to the new
equipment will take several months.
The MGC-100 is controlled by an operator through a Microsoft Windows 95 or Windows NT
interface over an Ethernet LAN, the Net or a dial-up connection. The unit starts around
$80,000 for an eight-port configuration.
William Jackson is a Maryland-based freelance writer.