单项选择题
What could a MS do when its state changes from idle to ready？（）
A.Power on B.PDP context activation C.GPRS attach D.Transferring packets
单项选择题 When does a MS get IP address？（）
单项选择题 Old SGSN can get new SGSN’s IP address by communicating to （） when a MS requests inter_SGSN RA update.
单项选择题 SGSN gets GGSN’s IP address by communicating to （） when a MS makes PDP context activation.
