Method and arrangement for detecting a malfunctioning terminal

A terminal evaluation unit for detecting a malfunctioning terminal in a cellular network, said terminal evaluation unit comprising:

• a receiving unit adapted to receive connection data from at least one network node in said cellular network, wherein said connection data is referring to connections of terminals when present in cells of said cellular network;
• a calculating unit adapted to determining, from said connection data, a mean connection drop rate for said terminals when present at least in a first cell during a first time period;
• a determining unit adapted to determine, from said connection data, an individual connection drop rate associated with a first terminal in said preset time period for at least one of said first cells;
• a deciding unit adapted to decide whether or not the first terminal is malfunctioning, based on a ratio between said individually connection drop rate and said mean drop rate;
• and
• a providing unit adapted to provide a result from the deciding unit to a cellular network operator;