A Linked-List Data Base Approach to the Control of the Digital Transmission Facilities of the Defense Communications System

An approach to the technical control of the digital transmission facilities of the defense communication system has been described by Jankaukas, Landesberg, Spector and Meyer (ref. 1). The status monitoring and performance assessment functions of that approach are interesting and the fault isolation algorithm is sound in principle. In this paper we report on the results of a study aimed at improving on that fault isolation algorithm with respect to removing certain network partitioning restrictions, decreasing processing time and making it compatible with channel reconfiguration and other resource management options. In our approach, the communications system is described in terms of two linked-list data bases, these being the equipment data base and the communication path data base. For fault isolation, the basic idea is that whenever an exception report is received, pointers from the alarmed piece of equipment point to the paths in which the equipment is located. For each such path, the equipment has an ordinal number stating its position in that path. For an alarmed equipment in a certain path, the equipment ordinal number is compared with the ordinal number of the most up-stream (in the transmission case) faulted equipment. Comparison of the ordinal numbers quickly indicates whether the alarm is real or sympathetic. This approach has been investigated using computer simulation. Channel recogfiguration and management of resources on the basis of needs and priorities have also been shown to be compatible with use of this algorithm.