H.323 Video Conferencing - High End Room Systems

Version: 1.1
Status: Proposed: 5/18/01
Contact: Teresa Thomas

Purpose:

To provide a set of guidelines for the selection of H.323 full screen "high end" room video conferencing systems.

Scope:

This guideline defines the technology tested for full-screen options for "best effort" H.323 point-to-point video conferencing within the VCCS.

Applicability:

This guideline is applicable to all colleges and campuses within the VCCS.

Definitions:

"Best Effort" is the attempt to use available bandwidth up to the maximum requested.  Bandwidth is not guaranteed to be available.  The application uses what bandwidth is available and competes with other video, voice and data for resources.

"High End" has more features which are required to support a larger room and/or group.

Guideline:

The H.323 standard contains the functionality of H.320 and H.321, but utilizes IP networks with packet-switching to transport multimedia and video conference traffic. The Standard spans the technical requirements for narrow and wide band visual telephony services that include one or more LAN's. H.323 recommendations cover the IP devices that participate and control H.323 sessions and the elements that interact with the switched network. H.323 allows for any combination of video, voice, and data to be shared between clients, thus allowing more flexibility than older video standards making this an option for future migration.

Potential uses of the H.323 video technology include the following applications:

1. Conduct face-to-face meetings for small groups.
2. Conduct face-to-face group meetings with multiple H.323 desktop clients (video/audio or both), or Netmeeting participants.
3. Participate in video streaming broadcasts.
4. Support at least 2 other collaborative inputs. (ie. video, elmo, data monitor)
5. Share documents, spreadsheets, files, and collaborative white boarding ideas.
6. Interact with colleagues, inside and outside the VCCS, without the extra travel and time expenses associated with current meetings.
7. Distance learning, counseling, security and more.

H.323 requirements:

• Support H.323 and T.120 ITU Standards.
• 30fps.
• Support G.722 audio compression.
• Support multiple video inputs and outputs.
• Support a minimum of 30 inch TV monitor.
• Support customer based scheduling.
• Capable of expanding the scope of videoconferencing to support variable speed connectivity capabilities. Low-end 384 Kbps up to 1.5 Mbps.
• Support automatic adjustable bandwidth control.
• Support comprehensive configuration for audio, video and collaborative computing.
• Provides network monitoring tools.
• Supports H.323 Gatekeeper functions which manage "network loading" by enabling administrators to restrict available bandwidth for conferencing, eliminating the congestion and blockage of other types of traffic simultaneously using the network.
• Conferences should adapt to endpoints with various capabilities. For instance, an audio-only client can participate in a conference with clients that support video and/or data. An H.323 compliant multimedia terminal can share the data portion of a videoconference with a T.120 data-only terminal, while sharing, video, audio and data with other H.323 clients.
• Support Interactive Multicast.
• Provide PacketAssist technology for QoS.
• Support Voice-only calls over IP.

VCCS Pilot Project

It is apparent from the research that in order for groups to participate in full screen videoconferences the system must support more capabilities than a desktop system. In order for full screen group systems to be successfully implemented, it is necessary to increase camera, microphone, speaker and codec quality to accommodate a larger number of participants.

To handle the larger room, the video requires a pan/tilt/zoom camera with supporting software in the codec to optimize display for the group. The camera needs to be able to handle pre-sets and camera controls (local/remote). Audio requires echo-cancellation, and an omni directional microphone to pick up voices within the room. As a minimum, multi-media speakers or forward facing stereo speakers in the monitor are required. Additional ports on the codec should allow additional input devices (VCR, Elmo, Monitor, or Data VGA). NTSC (Composite) or S-video (Digital) monitors may be selected based on the size of the room.

Full screen room videoconferencing is supported through the existing switched campus network and Net.Work.Virginia at a "Best Effort" level of service. This is due to the limitations of IP and Internet technology.

In the next phase of research, the goal is to develop an effective model and guideline for managing and operating H.323 videoconferencing services over the campus network and Net.Work.Virginia. Specifically, how is the traffic managed on the campus network and Net.Work.Virginia to ensure efficient use of the available bandwidth and the best possible service.

Vendors Tested:

VCON provides the Media Connect room systems that include the ability to participate in IP/TV video broadcasts within a LAN or WAN. This system has been tested up to 1.5 Mbps at a "best effort" across the network. If bandwidth becomes "unavailable" the system is capable of automatically adjusting during a conference so the session is not dropped when the bandwidth congestion occurs. These are proprietary features of this system.

This system includes an industry standard Intel PC, which contains a codec, network interface card, video cards that are optimized to run with the system, Sony pan/tilt/zoom camera, and omni-directional microphone. Additionally, M$ Office 2000 and VCON software are pre-loaded on the multi-media PC.

Polycom ViewStation features full screen video at 30 fps at 384 Kbps/512 Kbps, full-duplex digital audio, voice tracking camera, Web-based integrated interface in a small foot-print system. This system will support higher bandwidth in the future.

Intel TeamStation features allow users to conduct a 384 Kbps video conference at up to 30 frames per second. Wideband audio provides rich sound for meeting participants. Microsoft NetMeeting* is fully integrated into the simple user interface for easy-to-use data sharing.

Supporting Video Conferencing Requirements:

Network:

Full screen video conferencing will use the existing switched campus networks and Net.Work.Virginia as the methods of transporting video, audio and data from one desktop, server or room video system to one or more video enabled systems within or outside of the VCCS. The ITU H.323 Video/Audio and ITU T.120 Data Sharing Standards will ensure interoperability between desktops, conferencing rooms and conferencing centers.

Available bandwidth, video/audio hardware and encoding and/or decoding compression rates will affect video quality across "best effort" networks. Network congestion will also impact videoconferencing calls, as bursty data traffic competes with H.323 videoconferencing traffic. All of these variables affect what we see, hear and share on our existing campus networks and Net.Work.Virginia. Guidelines have been developed for minimizing the potential impact of network congestion.

Video Connectivity:

The minimum components of the High End Videoconferencing include:

Room:
An area suitable for video, audio and/or data collaboration. Lighting and acoustics must be sufficient to support larger room videoconferencing requirements. The room should be wired with category 5 cabling, electrical power, telephone, and have at lease one connection to the campus network.

Network
Any switched LAN, with connections to high speed interface to other LANS, running TCP/IP Transmission with the available bandwidth options for 64K, 174K, 384K, 784K, and 1.5 Mbps, bi-directional per call.

Video Bridges (Multipoint Control Units - MCUs):
Video bridges provide multipoint connectivity among multiple H.323 systems. They can also be used to transcode end point capabilities in both point-to-point and multipoint conferences. Bridges may be configured for any combination of conferences, up to the total number of ports on the bridge. The VCCS bridge currently supports a maximum of 768 Kbps per connection. However, the speed is due to be upgraded to 1.5 Mbps by September 2001.

Full Screen Videoconferencing System:
A system that meets the minimum requirements outlined above. An individual or group should be able to schedule a videoconference any time, based on the availability of the high end videoconferencing system and network resources. Multipoint conferencing will require the scheduling of the conference and notifying attendees of the pending meeting. A Web based scheduling application is being purchased for this purpose

Roles and Responsibilities:

Technical support:

Level 1: College staff/faculty will support room video configurations, installations, training and troubleshooting. College technical support staff will ensure local area network and campus Net.Work.Va connection will support number of proposed desktop video conferencing PC's.

Level 2: Utility Call Desk will be responsible for basic troubleshooting and are expected to resolve routine problems related to video services solve most minor problems immediately, and refer more complex problems to the appropriate product specialist as quickly as possible. Repetitive problems should be brought to the attention of the Utility Product Specialist.

Level 3: The Utility Product Specialist will work with college support staff and vendors to research complex and non-routine problems and provide their resolution. Additionally, the Utility Product Specialist will be responsible for the following: distributing configuration information, updates, usage documentation and testing new releases with the consulting support of Advanced Technology Engineers and the vendors.

Usage:
Individual staff/faculty/student will be responsible for learning how to use technology, security and scheduling the use of the resource(s).

Summary:

The H.323 Full Screen High End systems were tested within the VCCS. Each system was compared based on performance, sustained quality of video/audio, ease of use, and the compliance to stated requirements. Vendors having the additional ability to extend the H.323 to access other installed video applications were documented and demonstrated. Once example of this was the ability to tap into IP/TV broadcast streams which would give the room the flexibility for both administrative and distance learning clients to receive system or college broadcast when and where they need these services.

Multipoint capabilities continue to be somewhat limited in its capabilities and currently support 768 Kbps conferences. This is to be increased to 1.5 Mbps in the September 2001 timeframe. MCU's may be used most successfully with the lower bandwidth videoconferences and data sharing between different T.120 systems. Further technology research in the following areas will solidify multipoint desktop conferencing: advancement in MCU software capabilities, networking, management tools, and definition of the clients expectations of multipoint video and audio sharing requirements.

Video quality will continue to improve through the use of quality of service (QOS) features, vendor network management, and continued application maturity.

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