Abstract: A data communications system (100) has a controller (214) for managing the system containing a plurality of data communications devices (224). The data communication devices (224) have memory allocated for storing controller configuration information in order to serve as distributed controller backup units (226). If the controller (214) is replaced by a replacement controller (228), the controller configuration information is restored to the replacement controller (228) which receives the controller configuration information previously stored in the memory of the data communication devices serving as distributed controller backup units. The controller configuration information is stored in a page format (390) having identification (391), controller configuration information data (392), and error detection information (393).

Abstract: A data communications system (10) has a system management controller (100) and multiple data communications devices (21-1 through 21-n). The system management controller has a processor (110) and random access memory (115). The various data communications devices (21-1 through 21-n) are coupled to the system management controller (100) through a common address bus (12) and a common management bus (11). Through the processor (110), the system management controller (100) sequentially addresses each of the data communications devices (21-1 through 21-n) at a default data rate and determines a requested data rate for each device (FIG. 6, 305-333). The system management controller (100), through the processor (110), stores this requested data rate information, correlated with the address of each data communication device, in the random access memory (115) (FIG. 6, 305), and communicates with each such device at its requested data rate (FIG. 6, 335; FIG. 10, 500-545).