There is no magic formula. Good lighting, acoustics, and preparation are the keys to success. For example, a system located in a cinderblock room will sound bad at both ends. There's a bevy of websites with information on this subject, here are a few:
Some systems can add up to five remote systems to a single videoconference without using a video bridge (three sites is most common). However, be aware that your location may not have sufficient Quality of Service (QoS) bandwidth to support the extra calls without impacting quality or using a lower connection rate. If you are unsure, contact your account manager or the Service Desk. This type of conference CANNOT be scheduled in TMS at this time. OET is working with the vendor to enable this function.
If the off-MNET location that you're trying to reach point-to-point has a routable IP address, test it in advance of the actual event by dialing the IP address. If the participant is unable to accept incoming calls (see below), arrange for them to dial in to you. If the location is to be part of a multi-point (bridged) call, contact the Service Desk. If OET has never connected to the location, there will be a small certification fee to cover the cost of testing (not including any long-distance phone charges).
OET can connect to IP, ISDN and switched 56K based systems. Addresses in the following ranges are not routable, cannot be dialed and will need to be the initiator of the IP call:
This is not a complete list. However, if it's on this list, it is likely that we can not dial the system.
Yes. If your system is not equipped to add an audio-only (phone) participant, contact the Service Desk. There will be a connect charge (higher if LD charges apply) if OET bridges the call for you.
Check the Video White Pages or call the Service Desk.
Call the Service Desk for help.
In general, the following ports are required to be open:
| port | type | protocol description |
|---|---|---|
| 1719 | Static UDP | Gatekeeper RAS |
| 1720 | Static TCP | Q.931 (Call Setup) |
| 1024-65535 | Dynamic TCP | H.245(Call Parameters) |
| 1024-65535 | Dynamic UDP (RTP) | Video Data Streams |
| 1024-65535 | Dynamic UDP (RTP) | Audio Data Streams |
| 1024-65535 | Dynamic UDP (RTCP) | Control Information |
In almost all cases, the system behind the firewall must dial the connection to your system or bridge. OET offers best effort assistance in connecting to systems behind a firewall and has had many successful connections. Contact the Service Desk if the system you need to connect to is unable to dial your system's IP address directly.
OET will attempt to connect these systems on a best effort, time permitting basis only if the host site approves. If the webcam site causes interruptions or noise, it will be disconnected and may be re-connected by telephone. Currently, there are limited options for Macintosh-based webcams. There is one H.323 client (Xmeeting, http://sourceforge.net/projects/xmeeting/) that is known to work ok. Some other H.323 MAC clients may be available on the web under GNU public licensing or for purchase (untested). OET has no recommendation on this sort of client at this time, but we have tested with Xmeeting.
The H.239 duo-video function in videoconference systems is only capable of displaying the output of a PC or secondary video source from one location at a time, unless the PC is a participant in an external data conference like WebEx, it is view only.
Any Tandberg or Polycom H.323 group conferencing system has the ability to multicast into the local LAN. However, the LAN hardware must be capable of passing this type of traffic. The stream will not be available outside the LAN. OET offers best effort support for such events. One hint is to be sure the hop-count is set above 1 (try 3 or 4, but do not exceed 8. The lower it's set the better.).
The call rate is the bandwidth used for transmission and reception of both audio and video streams during a video call. The maximum rate is determined by your location's connection to the MNET core and the nature of your conference. Normally, 384kbps provides a quality picture for a typical "talking head" conference. If your conference contains a lot of motion (showing a movie, for example) or requires clear transmission of fine detail (e.g., American Sign Language translation), call rates of 768kbps are recommended.
The current limit for calls between different geographic locations (e.g.,, buildings or cities) is either 384kbps or 768kbps. However, calls between systems in the same building and organization (e.g.,, PCA calling from the 1st to 4th floor in their St. Paul location) can call at any rate their systems accommodate. If you need to call beyond your own location at rates above 768kbps, or you are currently limited to 384kbps, and you'd like an increase, contact your account manager.
You can place calls at any rate your system supports up to and including the maximum rate supported by the configuration at your location. Typically, county sites are limited to 384kbps. Other agencies and some education sites can go as high as 768kbps (many operate at 512kbps). If you want to be able to place calls at rates higher than currently configured, contact your account manager. OET does not recommend rates below 192kbps unless the site you're calling has a maximum below that rate.
If the connection rate selected exceeds the rate allowable by the gatekeeper your system is registered to, it will automatically reduce the call rate to the maximum allowed. If you have an event where a higher rate is required, contact the Service Desk. This may require registering your systems to a different gatekeeper, which may not be possible at all locations.
MNET bridges and the majority of installed systems support encryption. Once enabled, your audio/visual streams will be encrypted, providing the other participants have enabled encryption on their system as well. If you see an on-screen icon of a padlock or skeleton key, encryption is active.
In the TMS scheduling system, specify encryption as either:
This is the encryption indicator and means your audio and video data streams are encrypted for transport across the network.
On a set-top unit, the indicator light will be green when idle, amber when connected, and red if an error condition exists. If your system is connected to a touch panel or you have no access to the system, you may need to turn on a monitor to verify connection status. If in doubt, call the Service Desk and we can determine the system status for you.
There is no incoming audio mute other than turning down the volume. Remember to return the volume to normal before leaving the room, to avoid confusing the next users of the equipment.
The microphone mute button is on your remote. See the Polycom and Tanberg pages in the Equipment section on the left for information on remotes. Some Polycom systems have a button on the microphone. If the button is red, your microphone is muted. OET recommends you keep your microphone muted when not speaking while in conference with a large number of locations.
Still graphic snapshots can be sent from any valid source with the Snapshot button or soft button, depending on the system. It's best to practice using snapshots before the conference, especially for multi-point calls. It may be better to use the dual-video function or switch your active video source from the main camera to the graphics camera. See the Polycom and Tanberg pages in the Equipment section on the left for information on remotes.
This mode of operation is referred to as H.239, Duo-Video or Dual Video. Specifics:
Use the arrowhead keys on the remote control or the directional arrows on your touch panel. The main camera in almost all Tandberg and Polycom systems will pan side to side, tilt up/down and zoom in/out. Desktop systems often have a fixed camera mounted in the frame or a ball-mount. Ball-mount cameras can be moved manually. Both types come with a "digital zoom." Digital zoom is not a true optical zoom and may cause some distortion. Zoom controls on the remote either have a plus/minus indication or a head and shoulders icon (one small one larger). See the Polycom and Tanberg pages in the Equipment section on the left for information on remotes.
Call the Service Desk and ask for video support to reset your device to display menus in English. This will only be possible if OET can gain remote access to your system.
Any system with an integrated camera allows numbered presets. Once set, press the number on the remote to move the camera to the stored position. Consult your system manual for further details. It is a good idea to set presets for one or two-person framing and then create a room-layout map with indicators showing the area covered by each preset. However, these presets may or may not survive a power-down. On a Polycom, the camera will point to preset zero when powered up.
Once connected, most systems running in single monitor mode have some sort of picture-in-picture that will show your local room in a small, moveable inset picture in one corner of the screen to help you frame your outgoing picture.
Most systems have a set of jacks on the rear panel to accommodate a VCR (or other video playback device). Put the media in the deivce, press play, and select the VCR as the main source. If the recorded video is a stream coming from a PC, you should select the PC as your main video source (unless you're using a scan-converter). Be sure to connect the audio from the PC into the system. If using a PC to playback a recorded event, test it before the actual event. If your video system cannot take a PCs output directly, you may need a scan-converter to convert the VGA to TV video. Call your equipment vendor if a scan converter is needed.
Normally, these devices record the incoming video (and/or content) and audio from both ends of the call, but you should test it in advance and document how it works. Make sure your documentation is easily accessible to others using the system. OET will assist you in testing your VCR/DVD functions. Call the Service Desk to schedule a test.
OET can record any videoconference event for you as streaming media and burn it to a DVD. OET will supply the video on videocassette for a premium. This is a billable service and very reasonably priced. Call the Service Desk for details. Charges will vary.
Multi-point calls will end when the host disconnects at the conference end. You can also use the red hang-up button on a Tandberg remote (icon of a telephone handset with a slash) or press the green call button twice on a Polycom. Turning the system off will also work, but is not recommended. Remember, turning off the television does not turn off the video system; turn off the system for maximum privacy. see the Polycom and Tanberg pages in the Equipment section on the left for information on remotes.
The TMS scheduling system maintains call records from all OET gatekeepers. However, sharing these group records is a breach of privacy. OET is working with the vendor to allow individual client access to their own records, but currently you need to contact the Service Desk to have call records pulled. Please allow at least three working days for these reports.
