ITU-T H.325 (also called the "Advanced Multimedia System" or "AMS")
was a modern multimedia system project under development by the
ITU-T, specifically Q2/16 in the late 2000s
and early 2010s.
The purpose of the H.325 project was to create a new multimedia terminal and
systems architecture that supported distributed and media-rich
collaboration environments. A key element of that work was enabling
a plurality of devices and applications, each of which could be
independently developed by various hardware and software vendors, to work
seamlessly together to provide the user with a very rich multimedia
As an example of what H.325 would enable, it would have been possible to
simultaneously utilize a voice/video application on a tablet, file transfer
on a mobile phone, application sharing on a personal computer, and
whiteboarding using a dedicated physical whiteboard, all with virtually no
effort on the part of the user. The tight integration between these
applications truly increases the value of multimedia communications systems.
H.325 proposed an attractive, modern signaling syntax that used
JSON. The intent was to make it easy for developers to create
applications ranging from WebRTC applications to dedicated hardware and
Following the worldwide financial downturn in 2008, momentum on H.325
was substantially reduced. Work on the protocol proceeded slowly, but
was finally abandonded in 2015.