Fault diagnostics

A method of fault diagnostics in a case based reasoning system, wherein said case based reasoning system comprises a plurality of cases, each case having an associated solution and a case weight parameter indicative of the reliability of the associated solution, said method comprising the steps of:

• i) receiving data associated with a fault in a telecommunications network;
• ii) determining a case match score indicative of the degree of matching between the received data and each of the plurality of cases;
• iii) calculating a weighted case match score based on the case match score and the associated case weight parameter for each of the plurality of cases, and then providing a solution associated with one of the plurality of cases in dependence on the weighted case match scores and case weight;
• iv) receiving an actual solution to the fault, and
• a) increasing the case weight parameter of the case associated with the provided solution if the actual solution is equal to the provided solution;
• or
• b) adding a new case to the plurality of cases if the actual solution is not equal to the provided solution, wherein the actual solution is associated with the new case;
• and
• v) decaying over time the case weight parameters associated with each of the plurality of cases.