Patent ID: 8787173

Claim:
A communication system in which a base station sends packets to which numbers indicating sequence are attached, to a mobile station, the mobile station rearranges the packets in order of the sequence number, and hard handover is performed, comprising: a handover source base station having a controller that decides whether the handover source base station forwards packets which have not been sent to the mobile station, out of packets received from a host station, to a handover target base station or not, controls forwarding of the packets from the handover source base station to the handover target base station at the handover based on the decision, and sends forwarding execution information from the handover source base station to the mobile station to notify whether the forwarding of the packets from the handover source base station to the handover target base station has been executed or not, wherein the mobile station including: a receiver that receives the forwarding execution information from the handover source base station; and a controller that executes reordering of the packets received from the handover target base station based on the forwarding execution information at the handover.