Advanced Multimedia System Takes Steps

July 3, 2008

ITU-T Q12/16, the experts group focused on designing the next-generation multimedia communication system referred to as the Advanced Multimedia System (H.325), recently held a meeting in Chapel Hill, North Carolina. This was the first Rapporteur meeting of the experts group since ITU-T SG16 formally created the new group to begin work on the future multimedia communication system.

For those who are not familiar with ITU-T SG16, this is the Study Group within the ITU that has had a long history in the development of multimedia technologies, including the widely used ISDN video conferencing system (H.320), the hugely successful IP-based multimedia system H.323, data conferencing technologies defined in the T.120-series standards and utilized in such products as Microsoft NetMeeting, audio and video codecs like G.723.1 and H.264.

At this meeting, the group continued work on requirements and architecture. The group also worked to define terminology that will be used by the system, made plans for the various documents the group expects to deliver, and prepared an initial skeleton outline of the new draft Recommendation H.ams (planned to be H.325 when completed).

What makes H.325 unique is that, unlike legacy systems, "voice" is not the primary focus of attention. Of course, voice communication will be supported, but the main emphasis of H.325 is enabling multimedia communications, whether that is text, app sharing, file transfer, interactive gaming, voice, or anything else one might imagine. The design approach taken with H.325 is one wherein applications are logically and, quite possibly, physically separate from the user's "control" device (referred to as a "container" in the current draft specification). The interface between applications and the container will completely open and will be well-defined, which means that anybody can create a new application and make it available to users. The notion of "plug and play" is finally coming to your telephone! (But, with H.325, what is a telephone? Everything can be a part of the communication experience!)

Another significant difference between this new system and legacy systems is that the ITU has decided to utilize XML for the new system. The rationale is simple and logical: there is a tremendous amount of support in the industry for XML. The success of H.325 will depend on application developer support and XML is viewed as a key enabling technology. By using XML, a syntax specification that is widely understood and supported in every major development environment, application developers will immediately be able to create applications people can use.

To keep up with the progress of H.325, visit the H.325 Information Site and be sure to check out the document status page, which will be updated following every meeting. There are also mailing lists you can join to participate in or simply follow the work.