Guaranteed reliable broadcast network

A system that guarantees reliable data transmission for one-to-many and/or many-to-many communications amongst data processing stations includes several dedicated functions/stations distributed across a communications network. One or more general participant stations connected to a shared communications facility (e.g., a communications network) serves as a source and/or destination of information. A retransmission station receives input data from the general participant stations on a one-to-one basis, generates a special message header, and retransmits the message on the network. A designated recorder station ensures messages sent from the retransmission station are correct. This designated recorder station effectively communicates with the retransmission station on a one-to-one basis over the network, detects missed or corrupted messages, and can request the retransmission station to resend again. The designated recorder station also acknowledges reception of messages from the retransmission station. A playback recorder station listens to and stores the messages from the retransmission station either entirely or selectively. If this station detects missing or corrupted messages, it obtains the correct information from the designated recorder station using one-to-one communications. If a general participant station detects missing or corrupted messages, it obtains the correct information from this playback recorder station using one-to-one communications. A powered off general participant station can regain all the missed messages from the playback recorder station. An optional management station controls orderly start and stop of group communications or conferences and may also handle secure, confidential communications. Examples are provided to show how this guaranteed, reliable, one-to-many or many-to-many system can be applied to overcome previously unsolved problems.