A method for providing real-time multimedia conferencing services is described over a hybrid network, consisting of packet-switched nonguaranteed quality of service local area networks and a cell-switched wide area network having a multimedia bridge connected to the wide area network. The local area networks and the multimedia bridge are interconnected to the wide area network via routers. New architectural entities within the multimedia bridge execute a multimedia performance and resource analysis algorithm and determine whether the network and the bridge have sufficient resources to satisfy the requirements of the multimedia conference call. If sufficient resources are not available, it is determined whether the requirements for the higher priority services can be provided by preempting the lower priority resources. Signaling information messages are exchanged between the communicating entities indicating whether the multimedia conference can be accepted, rejected, or accepted to operate in degraded mode, based on the analysis performed by the bridge.