Methods of establishing multimedia telecommunication (a multimedia "call")
between equipment ("terminals"). More particularly, the invention
provides methods for reducing the time required to establish calls
between terminals that implement the ITU-T H.324 Recommendation and other
Standards and Recommendations derived from or related to this such as the
3G-324M recommendation developed and adopted by the Third Generation
Partnership Projects (3GPP and 3GPP2). More specifically, it relates to:
(i) a method and apparatus for concatenating the H.245 messages that are
required to pass between the terminals at the start of the call to
establish the capabilities of both terminals and agree on the type and
format of media and data to be exchanged; (ii) a method and apparatus for
using non-standard H.245 messages or standard H.245 messages with
non-standard fields to accelerate such establishment; (iii) a method and
apparatus of informing each terminal of the capabilities of the other and
proposing the type and format of media and data to be exchanged by means
of any user-defined fields that are inserted in the call signaling
protocol that is used for bearer establishment prior to the start of the
H.324 stage of the call; and (iv) a method and apparatus of informing
each terminal of the capabilities of the other and proposing and
accepting the type and format of media and data to be exchanged by means
of a burst of bits optionally encoded for error control on the bearer
channel as soon as it is desired, preferably as the first information
transmitted on the bearer channel.