Method and apparatus for transporting multimedia information over heterogeneous wide area networks

Abstract

A method and apparatus for separately transporting each monomedia stream of a composite multimedia signal across a network, such as an ATM network, is disclosed. The transport of monomedia traffic over different network segments, which may or may not support all multimedia components, is disclosed. Each monomedia component, n, such as video, voice and data, of the multimedia session is separately transmitted over a connection having a capacity, C,. The capacity, C,, is generally specified in number of units of information, such as the bandwidth that should be allocated to the respective monomedia component for the duration of the call, or the number of ATM cells per unit time for the duration of the call. In an illustrative ATM network implementation, individual connections can be established for each monomedia component by assigning separate VP/VC identifiers to each monomedia connection. Jitter, due to synchronization problems, is controlled by allocating appropriate bandwidth to each monomedia component. In a preferred embodiment, the respective value of each monomedia connection capacity, C,, is adjusted so that the jitter among the individual monomedia components is minimized. The capacity, C,, assigned to each monomedia connection is preferably based on the types of media included in the session, and current network conditions and can be obtained from experimental or statistical profiles of various multimedia type sessions, or dynamically adjusted based on network traffic conditions.