Patent ID: 7889867

Claim:
A radio network controller for relocating serving radio network sub-systems, the radio network controller comprising: a receiver adapted to receive ciphering information and a state variable value from a source radio network controller, wherein the ciphering information comprises at least a downlink hyper frame number of a first signaling radio bearer or an uplink hyper frame number of the first signaling radio bearer; and a processor adapted to perform steps of: establishing an unacknowledged mode radio link control entity for the first signaling radio bearer; ciphering a first data in the unacknowledged mode radio link control entity using at least the ciphering information or the state variable value received from the source radio network controller; transmitting the ciphered first data to a mobile terminal; establishing an acknowledged mode radio link control entity for a second signaling radio bearer; determining a greater value between a downlink hyper frame number of the second signaling radio bearer and an uplink hyper frame number of the second signaling radio bearer; incrementing the determined greater value by one; and receiving a second data including a start value.