Abstract: A second set of telecommunication devices is arranged to substantially mirror a first set of telecommunication devices in order to provide redundancy. First and second computer modules are included, respectively, in the first and second sets of devices wherein each module is capable of providing operating system control of the system and both modules initially operating with the same operating system. Only one of the computer modules controls the system at a given time. One of the devices of each pair of devices in the first and second sets of devices is isolated from the corresponding other device. The isolated computer module is loaded with a new operating system and tested by allowing the new operating system to control the isolated devices. This permits testing of the new operating system while maintaining uninterrupted control which is provided by the other devices operating under the same operating system.

Abstract: A method and apparatus for transmitting messages from one processor to a plurality of other processors in a distributed processing system having no hardware message broadcast facilities. The transmitting processor includes a broadcast program process for controlling the transmission of any messages destined for a plurality of other processors. Different client processes in the transmitting processor request the broadcast process to transmit a broadcast message. The single broadcast process controls the number of individual messages which are sent out sequentially to each of the receiving processors in such a way as to ensure that the broadcast messages do not interfere with other message traffic that frequently has tighter delivery time requirements. The broadcast process transmits the broadcast messages to each of the plurality of recipient processors without waiting for acknowledgment response messages from any of these processors.