Patent ID: 8583181

Claim:
A method of operation of a basestation in a cellular communications network, the method comprising: maintaining a list of user equipments that are authorized to use the basestation; in response to a first registration request received from a user equipment that is not authorized to use the basestation: starting a timer; starting a count of registration requests received from said user equipment that is not authorized to use the basestation; and transmitting a first rejection message to said user equipment that is not authorized to use the basestation, wherein said first rejection message permits the user equipment to make further registration requests to said basestation; and in response to a subsequent registration request received from said user equipment that is not authorized to use the basestation within a first monitoring period after starting the timer: incrementing said count of registration requests received from said user equipment that is not authorized to use the basestation, the method further comprising, when said count of registration requests received from said user equipment that is not authorized to use the basestation reaches a predetermined threshold within the first monitoring period: transmitting a second rejection message to said user equipment that is not authorized to use the basestation, wherein said second rejection message prevents the user equipment from making further registration requests to said basestation.