Patent ID: 7114002
Filing Date: 2006-09-26
Classification: H04L

Abstract:
1. A packet retransmitting system for transmitting a packet including a sequence number for defining a sequence of data included in each of a plurality of packets through a network and retransmitting a packet which is lost during transmission, the packet retransmitting system comprising: transmitting equipment for transmitting the plurality of packets; and receiving equipment for receiving the plurality of packets sent by the transmitting equipment, wherein the transmitting equipment includes: a priority degree information attaching unit for defining a plurality of priority degrees indicating an importance degree of the data, producing a priority degree information value for each of the plurality of packets by using the plurality of priority degrees defined, and attaching the priority degree information value produced to the packet, a transmitting unit for transmitting a plurality of packets to which the priority degree information value is attached by the priority degree information attaching unit through the network, and a retransmitting unit for receiving a retransmission request for requesting to retransmit a packet from the receiving equipment after the transmitting unit transmits the plurality of packets and retransmitting the packet of which retransmission is requested in the retransmission request received, wherein the receiving equipment includes a receiving unit for receiving the plurality of packets sent by the transmitting equipment through the network and a retransmission requesting unit for inputting the plurality of packets received by the receiving unit, extracting a sequence number and a priority degree information value from each of the plurality of packets input, judging lost packets based on the sequence numbers extracted, detecting an important packet among the lost packets judged based on the plurality of priority degree information values extracted, and transmitting the retransmission request to the transmitting equipment to request to retransmit the packet detected; wherein the priority degree information attaching unit includes: a priority degree setting unit for setting an importance degree for each of the plurality of priority degrees, a priority degree memory for storing the plurality of priority degrees set by the priority degree setting unit, and a priority degree information calculating unit for producing the priority degree information value for each of the plurality of packets by using the plurality of priority degrees stored in the priority degree memory and the sequence number included in the packet.