Patent ID: 8284671
Filing Date: 2012-10-09
Classification: H04L,H04W

Abstract:
1. A data transmitting and receiving system, comprising: a relay device configured to be connected to an ad-hoc network; and a first terminal and a second terminal each of which transmits and receives data via the relay device, wherein the relay device includes: a receiving unit configured to receive an observation packet used for observing transmission quality, and data; a reception buffer in which the data is stored; a reception buffer managing unit configured to observe a loss rate of the data in the reception buffer; a packet information rewriting unit configured to write the loss rate into the observation packet as congested state information, the loss rate being observed by the reception buffer managing unit; a transmission buffer configured to store on a destination basis the data stored in the reception buffer; a transmission buffer managing unit configured to forward the data stored in the transmission buffer at a predetermined transmission rate on the destination basis; and a transmitting unit configured to transmit towards a destination the data forwarded by the transmission buffer managing unit, and the observation packet, the first terminal includes: a first transmitting and receiving unit configured to transmit and receive data and the observation packet; and a first transmission quality managing unit configured to write degraded state information in the observation packet, the degraded state information indicating the loss rate of the data between the first terminal and the second terminal, and the second terminal includes: a second transmitting and receiving unit configured to transmit and receive data and the observation packet; a second transmission quality managing unit configured to calculate a transmission error rate of the data in the data transmitting and receiving system by subtracting the loss rate indicated in the congested state information from the loss rate indicated in the degraded state, the loss rates being included in the observation packet obtained from the first terminal; and an error correction processing unit configured to execute processing on data to be transmitted, so that an error of the data is corrected when the data is received, the processing being executed according to the transmission error rate calculated by the second transmission quality managing unit.