User terminal, infrastructure processor, system and method for use in mobile communications

A user terminal (109) for use in a mobile communication system (100) which includes a processor (102, 311, 312) operable to monitor data intended to be sent via a communication resource (PDCH) of the system to another terminal (119) and to detect whether the intended data transmission conforms with one or more pre-defined rules defining well behaved data transmission and, if the violation of one or more of the rules is detected, to initiate a procedure to determine if the data transmission is allowed to proceed. The procedure may include producing an alert signal for sending to a processor (112) of an infrastructure (101) of the system. A processor (112) for use in an infrastructure (101) of the mobile communication system (100) is operable to receive an alert signal from the user terminal (109), to determine whether or not the intended data transmission is allowed to proceed and to issue a response signal for sending back to the user terminal indicating a result of the determination.