Videoconferencing

USB camera

Introduction

GridPP depends upon excellent communications between distributed groups/individuals. We rely upon low-cost IP videoconferencing facilities for operational discussions between multiple users at all levels. We aim to monitor/comply with evolving standards over JANET and use IP videoconferencing and associated application sharing as a working tool.

The industry standard for videoconferencing over IP is H.323. For personal/desktop conferencing we use this both point-to-point and multipoint. The latter requires the use of an MCU (Multipoint Control Unit).

Note that e-Science uses Access Grid, which uses a different videoconferencing protocol.

The general direction we adopt is guided by the LCG Report on Collaborative Tools.

Current Practice

(as of October 2007)

  • For International multi-point we link into EVO using H.323. You need to register in advance of your first meeting.
  • This incorporates better support for macs (but has a longer start-up time than the previously adopted VRVS).
  • Users link into a video conference via their windows desktop using a standard USB camera (e.g. those from Creative). Earlier recommendation was polyspan ViaVideo unit and before that a Zydacron PCI card.
  • For multi-point within e-Science in the UK we use Access Grid facilities which are available at each of the e-Science Centre sites. Note that this is a different technology (based on MBone tools) currently requiring booking (and set-up) by your local e-Science centre. Beyond this there are video-conference rooms at most Universities which can be booked through your local Computing Service.
  • A review (and appendix) of multi-site video-conferencing requirements for the UK e-Science Programme provides more detailed information.
  • For point-to-point this allows application sharing (also known as data collaboration capability) which works quite well.
  • For multipoint within GridPP in the UK we can also connect via a gatekeeper maaintained by the JANET Video Conferencing Service (JVCS) using their JVCS-OnDemand ) Service. Note, however, that this service is used relatively infrequently. Application sharing is possible, but current practice is to rely upon pre-prepared web pages with links to all source material.
  • Known Issues

  • Firewalls may restrict required ports. This may not be under your control, but in general these have been overcome at all sites within the UK (eventually). The current status is that these have been overcome for VRVS and EVO. The EVO manual has more port details in the appendix.
  • Polyspan (and other vendors of hardware video codecs) support only Windows and have no plans to support linux. Users of linux desktops - see notes on Gnomemeeting below, but if a hardware codec is mandated then you'd need access to a Windows PC or Mac (for the forseeable future).
  • Interworking between Access Grid and individual polyspan units require a validation process which has not really been tested.
  • MCU managers generally restrict use of software codecs such as those in NetMeeting and GnomeMeeting.
  • Netmeeting should also not be used to connect into VRVS.
  • Solutions?

  • We track developments from Ekiga (GnomeMeeting)/OpenH323 This is a good software-codec solution on linux.
  • There are comments on various H.323 solutions at the VRVS recommended desktop client page.
  • Contact

  • Any questions, comments or updates, please contact Tony Doyle