This short paper will document a demonstration given at the Third Ka-band C
onference, Sorrento, Italy, September 1997. The principal objective was to
illustrate interoperability over a complex hybrid satellite and terrestrial
Asynchronous Transport Mode (ATM) network. The network linked Ka-band sate
llites in Europe and in North America, via the European JAMES Research and
Development(R + D) Network, and the CANTAT-3 trans-Atlantic submarine fibre
. The ISABEL application facilitated Computer Supported Collaborative Works
pace (CSCW) among locations in Canada, Italy and the U.S.A. The demonstrati
on consisted of the presentation of one full conference session from Italy
to observers in Canada and the U.S.A., with the opportunity for the remote,
as well as the local audiences, to interact with presenters during the 'Qu
estion and Answer' periods. There were also short presentations from the Co
mmunications Research Centre (Canada), and NASA Lewis Research Centre (U.S.
A.).
The ISABEL application required two virtual networks, one to handle unicast
signals for control and monitoring, etc., the other to distribute multicas
t traffic. They shared a common star topology over point to point symmetric
al Virtual Paths (VPs) through the interconnected ATM networks. The three p
articipating locations were connected to a Network Node at the Communicatio
ns Research Centre (CRC), Ottawa, Canada over full duplex El (2.048 Mbps) c
ircuits. The application traffic from each ISABEL workstation was directed
to the Network Node, where it was combined. The Control Workstation, at the
Conference Centre, Sorrento, Italy, allocated window sizes in the combined
image, selected local inputs, and switched presentation material as requir
ed. The combined image was multicast from the Network Node to the three net
worked locations.
The overall network included the Italsat-2 satellite and the U.S. Advanced
Communications Technology Satellite (ACTS), the Canadian and Italian nation
al test networks, the European R + D network, and the CANTAT-3 submarine fi
bre. Copyright (C) 1999 John Wiley & Sons, Ltd.