1. A method of model based fault analysing in a base station in a mobile telecommunication system, the base station having: data processing means adapted to control the activities of the base station; a fault manager function realised by means of software code executable by the data processing means; a plurality of software and/or hardware resources adapted to realise functions of the base station and to transmit fault indication signals to the fault manager code; the method comprising the steps of: receiving into the fault manager a predetermined fault rule model of said resources in a fault rule configuration file; implementing a fault analysis algorithm of predetermined rules for analysing received fault indication signals dependent on said predetermined fault rule model; generating an analysis tree data structure dependent on the fault rule configuration file; receiving from one of said resources a fault indication signal comprising identification and classification information; retrieving an applicable fault rule in the analysis tree data structure dependent on said fault indication signal; evaluating the result of the retrieved fault rule applied on said fault indication signal; generating an alarm signal dependent on said result of the applied fault rule.