Internet2 Virtual Briefings

Technology Diagram
Presentations on Internet2 Virtual Events

We describe the Internet2 Monthly Briefings as being "Powered by the Internet2 Commons", the community effort to establish production services and R&D efforts around collaboration technologies.

Our objective is to find the optimal mix of quality, audience reach, and interactivity with the technologies we use. It is our plan to do more each time with collaboration technology in both the production and exploration arenas. We wish to support individuals at their desktops and groups gathered in meeting rooms or lecture halls. We want to support audience members who wish to just observe and audience members who wish to interact with the presenters and other audience members. We also want to reach a broad range of participants based on the content of the briefings. These goals mean that we must use a mix of technologies to support these events, rather than just one solution.

Our intention is to have, by the end of 2002, an environment that supports people interacting with each other regardless of the underlying videoconferencing technology each uses. We will do this without dropping down to the lowest common denominator of audio and video encoding.

This document addresses audio/video conferencing and audio/video streaming. Right now we also provide downloadable and web-based slides/graphics. In the future we plan to provide other collaboration services, such as chat, screen sharing, etc.

Each time we will take into consideration the speaker locations and the typical audience for an event to determine the mix of technologies used.

For the observe-only audience:

• We will always distribute a Real Stream.
• We may add both a Windows Media stream and a QuickTime stream.
• We will typically stream at 512 Kbps.
• We will always provide IP/TV multicast streams (MPEG-1 at 1.5 Mbps).
• We will support VRVS.
• We will occasionally provide a dial-in audio conference service (depending on the desire of the session organizer).

During interactive sessions, the following technology will be supported:

• We will always provide H.323 access via the Commons multi-point control units (MCUs). This will typically be at 768 Kbps using H.263 compression.
• We will occasionally provide a dial-in audio conference service (depending on the desire of the session organizer).

For the presenters:

• We will always accept feeds from H.323, MPEG-1, and MPEG-2. VRVS, Access Grid, RTP/tv and MPEG-4 may be supported. We have H.323 and MPEG-2 loaner equipment we can provide to presenters.

Our biggest challenges are in providing gateways among technologies, particularly for supporting interactive sessions between different endpoint technologies.

Other technologies we intend to support and the issues they raise:

• We will support the Access Grid. This is straightforward for observe-only audiences in AG sites—however, this defeats the purpose of the Access Grid. A challenge is in providing gateways for the AG to and from other technologies. For example, while it is possible to grab an Access Grid window, scan convert it, and re-encode it for interactive or streaming services the quality of the image is degraded. Therefore, we will investigate providing a software transcoding option—but managing this amidst all the possible flows will be difficult. Going the other way, we also need to determine a means for someone in an Access Grid-enabled room to interact with a presenter using a different technology. For presenters in an Access Grid-enabled room we may have the presenter's camera and audio feeds be split from the source and sent out both directly to the Access Grid and encoded at MPEG-2 for gateways provided by Internet2 for other technologies.
• We can support MJPEG using RTP/tv for both speakers and audience members. We will both provide the presenter's feed in its highest quality format and gateway it to other technologies.
• For MPEG-2 we support hardware from Amnis (Optivision), VBrick, Ncast, and Litton for speakers. For audience members we will support at least one MPEG-2 technology for most briefings.
• Middleware is another research area for the Commons, working jointly with the Internet2 Middleware Initiative. Specifically, during Spring/Summer 2002 we will begin working on integrating the Session Initiation Protocol (SIP) into the Commons infrastructure, likely starting with some modest interoperability tests. During the second half of 2002 we will also begin investigating authenticated access to Commons events using deliverables from the Shibboleth Project. For the foreseeable future, all general interest Internet2 sponsored efforts, such as the Monthly Briefings, will be available to anyone with an internet connection. However, there will be specific areas, such as working group meetings, that may wish to have access control mechanisms.
• The effort to date has revealed a number of issues related to end-to-end performance (poor video and audio connections), production challenges (lighting, sound, and camera positioning), and education (e.g., remembering to mute one's mic if not a speaker). We intend to make progress in these areas:
  Provide testing for speakers and audiences
• Work with End-to-End performance groups
• Develop technologies to improve performance
• Document best practices

If you have questions or input on these plans, please contact Ted Hanss.