Dialling up an H.323 node from an Access Grid node.

An Access Grid node can use the H.323 - AG bridge to dial up an H.323 node and connect it to the Access Grid virtual venue. The IOCOM (inSORS) servers run by the AGSC have this bridge built in so that IOCOM IG clients can make this connection. AG Toolkit users would need to request that an IG user within their organisation or someone at the AGSC to initiate the connection when no local IG clients are present.

It is also possible to bridge a EVO client to an H.323 client.

The following list displays the procedure for using an IOCOM IGDialer to dial-up an H.323 node:

1. Enter the virtual venue 'bridged' and not multicast. Any virtual venue can be used.
2. Obtain the IP address of the H.323 node that you want to connect to. The node administrator of the H.323 node will be able to provide you with this. Make sure that the H.323 node administrator is aware of the hostname or IP address of the machine running the H.323-AG Bridge Server that you're using, in case there are firewall restrictions at their end.
3. Click on the telephone icon (as shown below) that is situated on the bottom LHS of the main IG window.
   
4. Input the IP address of the H.323 node, including all points between digits. See image (below) that uses example IP address 123.45.67.89.
5. Click 'Call' and check status.
6. If 'Connected to ip$123.45.67.89' is displayed, the connection is successful.
7. If possible, only transmit one video feed. The H.323 node can only receive one at a time anyway (see note below).

In some instances a Gatekeeper connection is required when bridging to an H.323 node. This type of connection is configured within the 'Advanced' section of IGDialer.

Note: H.323 nodes can only receive one video feed at a time. Once bridged to an Access Grid virtual venue, the H.323 node will only see the video feed that has been set to 'Primary'. The primary video can only be set by an IG node operator who is connected to this meeting. Only one video feed out of the combined video feeds from all the Access Grid nodes can be set to 'Primary' at any time. The Primary video window can be changed at any time during the meeting. Any IG client connected to the virtual venue can set their own or anyone else's video feed to be 'Primary'. This is achieved by clicking the mouse cursor on the AG video feed window and pressing the number '1' key on the keyboard such that '#1#' is displayed at the top of that video feed window. The H.323 node operator cannot choose which video feed will be 'Primary'.

Please also be aware that the video resolution transmitted by H.261 Access Grid clients is less than the equivalent H.323 Video Conference client. Therefore the quality of video may appear lower when viewing the video feed from an Access Grid node, compared to the quality experienced during H.323 to H.323 meetings. It's also the case that the resolution of the video feed coming from the H.323 node is reduced by the H.323-AG Bridge Server, so AG users may not see the same quality of video that they would see when using only H.323 video conferencing. This is apparent with users who are temporarily using an AG node to connect to an H.323 node because, for example, their usual H.323 node is not available.

The institution firewall of the H.323 node may require configuration to allow access to/from the Bridge Server that you are using to bridge to them.

Support:

• If you want to practise dialling up an H.323 node, JVCS can provide you with the IP address of one of their test H.323 nodes. Please arrange such a test by contacting the JVCS in advance either by email: vidconf@jvcs.video.ja.net or phone: 0131 650 4933. Obviously this should only be requested if the actual H.323 node you're planning to connect to is not available to make test connections.
• It is possible for more than one H.323 node to connect to the Access Grid if each node first connects to an MCU, and then the H.323-AG Bridge will dial-up to the MCU, or vice versa. We strongly recommend a test connection before committing to a meeting that will utilise this setup.

*H.323 is a videoconferencing protocol that provides for connectivity over the IP network. In this context, H.323 facilities use videoconferencing codecs that are common across industry and academia.