Assessing LAN-based Videoconferencing Technologies
November 1997 - December 1998
The project was completed with the help of the following staff at UCL:
We also acknowledge the help and support of
, Project Manager, UKERNA.
ALAVIT was a project to provide a series of reports to facilitate
the widespread deployment of LAN-based videoconferencing and its interfaces
with WAN facilities. The current JANET
videoconferencing strategy recognises that the future use of
videoconferencing is likely to involve a variety of standards and
technologies and therefore requires that videoconferencing services be as
seamless and pervasive as is practical. This is seen to require the
appropriate use of gatewaying or other measures to ensure the interworking
and integration of heterogeneous technologies.
The aims of the project were to:
ALAVIT began with two surveys:
- assess currently available LAN based videoconferencing technologies and
- survey JANET users to identify which are in current use in the JANET
- identify the planning considerations for deployment of LAN based
- evaluate a sample of integration products, including gateways, and
produce a review of the technical options for their deployment; and
- make recommendations for the deployment of gateways in the JANET backbone
- available products with a comparative evaluation of their utility in
meeting the needs of the JANET community;
- current usage of such products by JANET users.
The survey of products included the Mbone tools shrinkwrapped in the
the H.323 tools developed in the ITU-T community, which were be the
subject of most of our efforts, and other tools such as CU-SeeMe. The survey
was done by web search, by direct request to major software suppliers and
trade associations and by enquiry of relevant special interest groups.
Products were categorised into groups braodly in line with the ITU standards
We also reported on their
standards compliance - IETF standards compliant, ITU-T standards compliant
or proprietary. The results of these surveys have been published as D1 below.
- End systems,
- Multipoint Control Units (MCUs),
- Gateways between LAN-based and other videoconferencing systems products and
- Gatekeepers, used to manage H.323 end systems.
The next stage of the project was the testing of an agreed subset of the
products identified in the survey. The results of this testing was reported
in D2 below. Products were selected for testing to give a
representative review of the available range subject to their availablility
for testing. A similar activity evaluated the integration products which
address the interaction between H.320 tools using native ISDN and H.323 tools.
The report contains both technical statistics and observations of users,
which address bandwidth utilisation on the LAN and quality of service as
perceived by the user. It also discusses related activities such as the use
of the products in linking LAN-based conferencing to the wider area - campus,
metropolitan and wide area networks, including ISDN.
The results were used also to make specific proposals to UKERNA on the
deployment of gateways in the backbone network.
Deliverables are available from the
UKERNA web site for the project.
Last updated 22 March 1999 by email@example.com to whom all enquiries should be addressed.