Video Conference facilities for EUROMET activities

Final Report, 8 April 2005


Videoconference equipment (Polycom Viewstation SP128) was implemented and tested at DFM. Technical problems when using the equipment behind a firewall were solved. A point-to-point conference between DFM and PTB took place in June 2004 where the advantages of videoconferences as well as more practical issues were discussed. Methods for sharing documents during a videoconference were studied.

In the fall of 2004 a questionnaire on videoconference facilities and experiences was sent to all EUROMET contact persons in the field of interdisciplinary metrology. A summary of the questionnaire replies is given in Appendix A.

In December 2004, University of Southern Denmark and DFM participated in a point-to-point conference during an internal DFM-seminar where document sharing in Microsoft Netmeeting was demonstrated.

A multipoint videoconference was organized in March 2005 between DFM (5 persons), Aalborg University (9 persons), Aarhus University (2 persons) and Danish Research Network (1 person). Danish Research Network is a high-speed Internet supplier designed for Danish universities and research institutions. Both Continuous Presence (four small pictures of each location simultaneously) and Voice Switching (one large picture of the location/person who is talking) was demonstrated as well as document sharing (Power Point) among all four locations via Microsoft Netmeeting. The two universities and Danish Research Network have groups with experience in videoconferencing both for teaching (E-learning) and as alternatives/supplements to face-to-face meetings. People with low or no experience were invited to participate at all locations. Experience, expectations, techniques and advantages were discussed.


The questionnaire shows that videoconferencing is not yet widespread within EUROMET although a few NMI’s are considering or testing different systems. Only two NMIs seem to use videoconferencing regularly (PTB and SP). More NMIs will have to invest in equipment before EUROMET meetings can take advantage of videoconferencing, but some NMIs are likely to delay such investments until the ‘critical number’ has already been reached and an immediate advantage can be seen.

It is, currently being considered whether document sharing, voice over IP and possibly videoconferencing can be used efficiently within the iMERA project. This project could be the test case for a wider EUROMET position on videoconferences.

We have in this project focused on IP-based videoconferencing. Another possibility is ISDN-based solutions. However, IP videoconferencing does not require installation and maintenance of an additional ISDN network, and ISDN has relatively high per minute usage fees – in particular for international conferences. IP-solutions allow in principle a simple PC with a web-camera to participate in a conference, e.g. via Microsoft Netmeeting, although this particular software product may suffer from compatibility issues when interfaced to other equipment (see the link to a compatibility survey below). Furthermore, ISDN connections are very sensitive to the reliability of the multiple data lines used simultaneously for reaching an acceptable bandwidth. In contrast, the IP-solution may suffer package loss resulting in freezing images and pixel errors in an environment with insufficient bandwidth or without Quality of Service (QoS) management. Some companies and institutions require ISDN conferences for security reasons.

Videoconferencing with video and sound usually follows the H.323 protocol, and there are generally few problems in interfacing equipment from different manufacturers. If the conference has more than two participants a Multipoint Control Unit (MCU) is required. Some systems have an integrated MCU or alternatively an external MCU can be used. DFM has access to an external MCU via the Danish Research Network.

There are several solutions for document sharing. We recommend using Microsoft Netmeeting, which allows document sharing via the T.120 protocol. This requires an additional connection independent of the H.323 videoconference connection, and it may require an additional MCU for more than 2 users. Microsoft Net-meeting has the advantage of being standard software on a Windows PC, and it can be configured behind a firewall without compromising security. Whereas difficulties may arise when interfacing Microsoft Net-meeting to other videoconference equipment, we have not observed difficulties when Netmeeting is used for document sharing only.

Because of the technology involved and time delay in the audio and video signals, a videoconference requires more planning, discipline and etiquette than a face-to-face meeting – in particular in the case of more than two participants. Less experienced participants are recommended to do an internet search on “videoconference tips”

before the first conferences.

The videoconferences mentioned above, and in particular the multipoint conference, was considered a success by the participants. Although the picture quality suffered a bit from time to time, the audio quality was fine and the document sharing worked without problems. Some time must be reserved for setting up the conference, in particular multipoint conferences and document sharing.

Two groups had experience with how much travel costs could be saved. Out of the regular meetings in the National working group on videoconferencing, 1/3 is now held by people traveling; and the Danish Research Network had experienced a substantial cut in traveling for internal meetings for users with several locations.

Videoconferences can be used as a supplement to phone, email and face-to-face meetings, although it cannot replace all such meetings. In particular, videoconferences may be useful as a replacement for some of the regular meetings between groups of people who know each other already and for more informal discussions of documents.

Details on the compatibility of different videoconference systems are available at



We recommend that the use of videoconferences within EUROMET be intensified in the future.

We recommend that both point-to-point and multipoint (up to four sites) be implemented for use within EUROMET.

A workshop is planned to give people a practical experience with the currently available practical possibilities. The workshop should take place at PTB, DFM, and SP, see Appendix B for a proposed agenda.

Feasibility Study for the usefulness of Video Conference facilities to assist EUROMET activities.

The final purpose of the project is to achieve savings in expenses and time used for attending EUROMET meetings. DFMs budget for attending EUROMET meetings is 15.000 EUR/year. If just 20% of the meetings could be made by Video Conferencing - the payback time will be 18 month, and additional meetings by Video Conferencing will be “free of charge”

The project will specify equipment required for Internet for Video Conferences.

It is proposed that Video Conference Equipment should follow the ITU Standard H.323.

Equipment necessary for each participant of a Video Conference could be:

PC with Windows 98/Me/2000

Video Conference Kit compatible with H.323 and T.120 (software, camera, microphone, etc.), for example VCON ViGO at app. 4.000 EUR.

Each Video Conference needs one “Multipoint Conference Unit” (MCU), a MCU is part of many networks, and is available “free of charge” on the Danish Research network.

While H.323 equipment is compatible with respect to Audio and Video, not all of these have a “Whiteboard”, Application and Data Sharing” (e.g. PowerPoint slides) as defined in T.120, VCON ViGO has a “Whiteboard”.

Further Information

Video Conferencing could be used as a tool to close the gap between contact by e-mail (or phone) and meeting at locations.

Interdisciplinary Metrology (IM)
Jan Hald (DFM)
Coordinating Institute
DFM (Denmark)