A method and base station controller (BSC) in a GPRS/EDGE cellular radio
telecommunication system for controlling a handover of a mobile station
(MS) conducting both a circuit-switched call and a packet data session,
and for rapidly reestablishing the packet data session. The BSC
determines from measurement reports that a handover of the MS is
imminent. The BSC sends both packet system information and Dual Transfer
Mode (DTM) information relevant in the target cell to the MS prior to a
handover command. When the handover is complete, the BSC may also send a
pseudo cell update message to a serving SGSN. The message includes an
identifier of the MS and appears to the SGSN to be from the MS. After the
circuit-switched call is reconnected, the packet data session is rapidly
reestablished utilizing the information sent to the mobile station prior
to the handover command, and without having to send a cell update message
from the MS.