A source base station eNB#1 forwards a header-compressed packet addressed to a radio terminal UE, to a target base station eNB#2, at a time of a handover procedure of the radio terminal from the source base station eNB#1 to the target base station eNB#2. Upon receipt of the forwarded header-compressed packet and a header-non-compressed packet addressed to the radio terminal UE from a core network EPC at the time of the handover procedure, the target base station eNB#2 generates an ROHC context corresponding to a header compression level of the header-compressed packet, by using the header-compressed packet and the header-non-compressed packet.