Packet data network switch having internal fault detection and correction

Abstract

A data network switch for switching data between a plurality of data links is disclosed and includes a programmable controller which adapts the data switching in accordance with the state of the switch and the state of the data links. The programmable controller has detection apparatus which detects a problem in the operation of the switch, a memory which stores information on possible problems, their causes, and possible solutions, and a controller. The controller determines from the information stored in the memory the possible causes of the problem according to the nature of the problem detected and determines from the possible causes a ranked series of possible solutions. In addition, the controller carries out the first of the possible solutions, checks the output of the detection apparatus after a predetermined period of time, and if the problem is still present, carries out the next of the possible solutions, and repeats the checking and carrying out of the next of possible solutions until the problem is no longer present or no further possible solutions remain.