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We have already stated that we expect to use H.261 for video coding. We know that the H.221 multimedia stream encoding is not appropriate for packet-switched operation, but believe we can overcome any inherent problems. We have also stated that we doubt that the standards for in-band audio coding are appropriate, because of our potential need to use a different network topology for voice than for video; some of the distribution sites may require only the audio, others may require reduced bandwidth audio with no video. We intend to use international standards again for audio - but these may come from a different domain such as cellular telephone. There are emerging standards for Multipoint Control Units (MCUs) required for multiple conferences; these are supplementary to H.221/H.261. We will have to investigate the assumptions behind these standards to determine how relevant these are, but will not be using them at first. Some Internet Standards developed currently under the auspices of the Audio Visual Transport Working Group (AVT-WG) of the Internet Engineering Working Group (IETF) seem more appropriate [22]. These determine framing standards, but describe the other elements in such a way that they can be passed through different networks and be reconstituted at the destinations. They also allow the specification of lifetimes for the elements, so that they can be destroyed if they are going to arrive too late at the destination - or alternately so that the priority of the elements can be changed at intermediate nodes. Of particular importance is that the coding permits different protocol versions to be used, this permitting heterogeneous implementations. Other features supported are flow control, end-to-end real-time control, media source and destination, conference announcement, and quality of service announcement. It is significant that the working group includes representatives from service providers such as AT&T.
Another set of standards are being developed by other IETF groups in Remote Conferencing (REM-WG) [23] and Conference Control. These were not available for the early stages of MICE, but the discussions have been followed, and the project's requirements have been put forward. There is already a concrete proposal that MICE be associated with a US NSF project, which would use the IETF Standards. The standards being developed in the working groups include the following: a Connection Conference Manager; an Applications Programming Interface; mechanisms for coding, transport, multicast and flow control; network resource management; multicast address administration; a connection and configuration manager, conference systems management.