Bits & Bytes online Edition

Trends in Videoconferencing in IPP & MPG

Ulrich Schwenn

Videoconferencing is used regularly for connections in- and outside IPPs sites in Garching and Greifswald. This comprises between 10-30 independent point-to-point conferences per week between rooms on both sites. Some of the rooms, namely the lecture hall in building D2, the seminar rooms 1 & 2 in Greifswald and the smaller rooms of the 'Wissenschaftliche Leitung', RZG, and the three meeting rooms in Greifswald are therefore used rather frequently.

New are the two rooms operated by ASDEX Upgrade - the big seminar room is equipped like the other big lecture halls, the smaller one for division E4 has been set up like the existing meeting rooms. In addition about 20 ViaVideos, small desktop units, are used on both sites by technicians and scientists.

A talk by U. Schwenn, given recently at CEA/DFRC in Cadarache, France is available in pdf format under the following two links:

IPP Scenarios

The RZG video group supports three scenarios - desktop, seminar rooms and lecture hall like rooms. The video conference clients recommended and used throughout IPP are ViaVideo desktop systems, Tandberg 500 and 880 settop systems and Tandberg 6000 for big rooms. These allow conferences between all scenarios. The user interfaces for the smaller two are easy and can be operated by anyone, the big rooms need a dedicated technician to assist the speakers during their presentations.

Gatekeeper, Firewall, Global Dialing Scheme (GDS)

All IPP VC systems and several (~ 20) external are registered on RZGs gatekeeper, an openH.323 Gnu software run on a Linux PC. Using the Global Dialing Scheme based on the E.164 standard of ViDeNet throughout IPP allows to keep all VC systems inside the RZG firewall. They are reachable only by their E.164 number by control of the gatekeeper. The structure of the numbering is as follows:

    [<EZ>] <worldgk>  <cc.>  <org.>  <client no> [<suffix>]

e.g. 00 49 140 1000 (Schwenn's ViaVideo at IPP).

The numbers allow standardized international and national access together with individual choice of local extensions (<client no>). See also

DFN Videoconference (DFNVC) Service:

As with April 1, 2003 the former pilot project of the DFN Verein for a Multipoint infrastructure for the users of the GwiN became operational. This implies for members of MPG, that they will have to expect a billing. Details are under discussion between DFN and the MPG general administration (GV). Until then the standard service and a beta version of the special MPG premium service can be used by anyone inside the MPG. It is obligatory to be registered on one of DFNs gatekeepers, the one of RZG or any other local gatekeeper which must be registered by DFN on the German country gatekeeper (see

For questions concerning choice of systems, gatekeepers etc. contact, the respective web pages of RZG will be replaced by an updated English version this summer.