Patent ID: 7920500

Claim:
A controller apparatus configured to control transmission of a packet from a source mobile terminal to a destination mobile terminal through a plurality of relay mobile terminals in an ad hoc network formed by a plurality of mobile terminals, each mobile terminal having a loss report transmitting unit, the control apparatus being distinct from the source and destination mobile terminals, the controller apparatus comprising: a packet location information managing unit configured to manage packet location information showing to which mobile terminal the packet has been transmitted in the ad hoc network, the packet location information associating packet identification information to identify the packet with mobile terminal identification information, by receiving completion reports that include the packet location information directly from any one of the source mobile terminal, the destination mobile terminal, and the one or more relay mobile terminals that has either sent or received the packet, and the completion reports are not relayed through any other mobile terminal; a detecting unit configured to detect loss of the packet in one of the mobile terminals of the ad hoc network, the detecting unit configured to receive a loss report from the loss report transmitting unit that is configured to detect a local loss in the corresponding mobile terminal that lost the packet; and a retransmission request transmitting unit configured to transmit a retransmission request for the lost packet to one of the relay mobile terminals that is managed as a current location of the packet, based on packet location information managed by the packet location information managing unit, wherein the retransmission request unit transmits the retransmission request for the lost packet to a relay mobile terminal that is located one hop before the relay mobile terminal that sent the loss report, in a case where the relay mobile terminal that sent the loss report cannot find the packet in a buffer.