Abstract: An apparatus for coupling data processing equipment to subscriber loops in a telephone system based computer network is disclosed. The multipoint communication network includes a plurality of network units with at least two of the network units comprising the apparatus in question. The network units are coupled to telephone system communication links. The network units transmit and receive digital data in a frame mode in which the data is organized into frames on the communication links. The network units also communicate with each other in a manner which allows the configuration and speed of the network to varied in response to the time of day and error rates observed on the telephone system communcation links.

Abstract: An apparatus for transferring digital data between time-domain multiplexed communication links of a telephone system which forms part of a computer network. A time-domain multiplexed communication link interface unit for transferring digital data between a first channel on a first time-domain multiplexed communication link and a second channel on a second time-domain multiplexed communication link of a multipoint communication network is disclosed. The multipoint communication network includes a plurality of network units with at least two of the network units comprising said time-domain multiplexed communication link interface units. The network units are coupled to telephone system communication links. The network units transmit and receive digital data in a frame mode in which the data is organized into frames on the communication links.

Abstract: Disclosed is an adaptive multijunction unit apparatus for multiplexing data streams between a master computer and a plurality of slave computers coupled through telephone system communication lines. The apparatus receives and processes both user data and network data which can include commands instructing the apparatus to change the operating modes of its various circuit components. For example, the adaptive multijunction unit apparatus can respond to commands to raise or lower its data transmission rate or to switch between dual channel and single channel data transmission. The apparatus includes a splitter/combiner function which copies data received from the master computer, onto output ports directed to multiple slave computers.