Abstract: A data communications device (101, 119) may be controlled from a centrally-located network management system controller (109) located some distance from the device. The data communications device is coupled to the network management system controller by a local channel (155, 157). The device includes a link adapter (133, 143) that communicates with the controller by a protocol that allows the device to exchange messages with the controller. As many as 512 devices may be coupled to the same local channel.

Abstract: A line powered data communication apparatus (DCA) includes dual programmed microcontrollers, one being interfaceable with data terminal equipment and the other for governing the operation of modem circuitry of the DCA which is interfaceable to a telephone line of a telephone network. The dual programmed microcontrollers interact with each other over an electrically isolated interface, preferably including optical isolators. Power is derived for the one microcontroller from the signal lines interfacing the data terminal equipment. In addition, power is derived for the other microcontroller and modcircuitry from the telephone line.

Abstract: A modem, or data communications device, that is testable independently of a DTE device permits remote testing of it automatically by a network management computer or controller reducing required operator intervention. A data communications network that has possibly hundreds of these modems requires substantially less operator intervention.

Abstract: A method for remotely configuring a modem in a communication system is described herein. Specifically, the method allows a modem user the ability to modify or view the options of a remote modem by placing the remote modem first into a test mode. The method, following the execution of the test mode, provides some security through the use of a security code which is programmable by the remote user. The remote modem is then placed into a reconfiguration mode, after which the local modem transmit commands to the remote modem using a bi-sync protocol to ensure accurate reception of commands and responses. The process of remote configuration is terminated by exiting the reconfiguration and test modes.