Packet communication method and device

A communication device connected to a network, comprising:

• a transmission unit configured to transmit a packet to other communication device via the network;
• a reception unit configured to receive, from the other communication device via the network, an ACK packet including information on a SACK and information on an ACK with respect to a packet transmitted from the transmission unit;
• a packet counting unit configured to count a number of transmission packets, which is a number of packets transmitted from the transmission unit;
• and
• a loss rate measurement unit configured to measure a loss rate of a packet transmitted from the transmission unit in a predetermined period based on the number of transmission packets and information on the ACK and the SACK,
• wherein
• the packet counting unit counts a number of ACK packets, which is a number of ACK packets received by the reception unit, and a number of duplicate packets in ACK packets received by the reception unit, which is a number of the ACK packets in which information on the SACK corresponds to information on the SACK of an ACK packet received just before the ACK packet, and
• the loss rate measurement unit measures the loss rate based on the number of transmission packets, the number of ACK packets, and the number of duplicate packets.

A communication device connected to a network, comprising:

• a transmission unit configured to transmit a packet to other communication device via the network;
• a reception unit configured to receive, from the other communication device via the network, an ACK packet including information on a SACK and information on an ACK with respect to a packet transmitted from the transmission unit and;
• a packet counting unit configured to count a number of transmission packets, which is a number of packets transmitted from the transmission unit;
• and a loss rate measurement unit configured to measure a loss rate of a packet transmitted from the transmission unit in a predetermined period based on the number of transmission packets and information on the ACK and the SACK,
• wherein the loss rate measurement unit changes a method for measuring the loss rate in a case where the ACK packet is not returned, in a case where a SACK packet is not changed, or in a case where an ACK packet is transmitted while being thinned out.

A communication device connected to a network, comprising:

• a transmission unit configured to transmit a packet to other communication device via the network;
• a reception unit configured to receive, from the other communication device via the network, an ACK packet including information on a SACK and information on an ACK with respect to a packet transmitted from the transmission unit;
• a packet counting unit configured to count a number of transmission packets, which is a number of packets transmitted from the transmission unit;
• and
• a loss rate measurement unit configured to measure a loss rate of a packet transmitted from the transmission unit in a predetermined period based on the number of transmission packets and information on the ACK and the SACK,
• wherein
• the packet counting unit counts a number of ACK packets, which is a number of ACK packets received by the reception unit, and a number of retransmission request packets, which is a number of packets requested to be retransmitted in packets transmitted from the transmission unit based on information on the ACK and the SACK, and
• the loss rate measurement unit changes a method for measuring the loss rate depending on a relation among the number of transmission packets, the number of retransmission request packets, and the number of ACK packets.

A communication device connected to a network, comprising:

• a transmission unit configured to transmit a packet to other communication device via the network;
• a reception unit configured to receive, from the other communication device via the network, an ACK packet including information on a SACK and information on an ACK with respect to a packet transmitted from the transmission unit and;
• a packet counting unit configured to count a number of transmission packets, which is a number of packets transmitted from the transmission unit;
• and
• a loss rate measurement unit configured to measure a loss rate of a packet transmitted from the transmission unit in a predetermined period based on the number of transmission packets and information on the ACK and the SACK;
• and
• a band control unit configured to control a band for transmitting a packet to the other communication device in response to a change in the loss rate, wherein
• the transmission unit transmits a packet in accordance with the controlled band.

A packet loss rate measuring method, comprising:

• measuring a loss rate of a packet transmitted from a communication device to networks;
• measuring a number of transmission packets, which is a number of packets transmitted from the communication device to the network;
• measuring a loss rate of a packet transmitted from the communication device to the network in a predetermined period based on the number of transmission packets and information on the SACK and an ACK included in ACK packet received by the communication device via the networks;
• measuring a number of ACK packets, which is a number of ACK packets received by the communication device, and a number of duplicate packets in ACK packets received by the communication device, which is a number of ACK packets in which information on the SACK corresponds to information on the SACK of an ACK packet received just before the ACK packet;
• and
• measuring the loss rate based on the number of transmission packets, the number of ACK packets, and the number of duplicate packets.

A packet loss rate measuring method, comprising:

• measuring a loss rate of a packet transmitted from a communication device to a network;
• measuring a number of transmission packets, which is a number of packets transmitted from the communication device to the network;
• measuring a loss rate of a packet transmitted from the communication device to the network in a predetermined period based on the number of transmission packets and information on the SACK and an ACK included in an ACK packet received by the communication device via the networks;
• and
• changing a method for measuring the loss rate in a case where the ACK packet is not returned, in a case where a SACK packet is not changed, or in a case where ACK packets are transmitted while being thinned.

A packet loss rate measuring method, comprising:

• measuring a loss rate of a packet transmitted from a communication device to a network;
• measuring a number of transmission packets, which is a number of packets transmitted from the communication device to the network;
• measuring a loss rate of a packet transmitted from the communication device to the network in a predetermined period based on the number of transmission packets and information on the SACK and an ACK included in an ACK packet received by the communication device via the networks;
• measuring a number of ACK packets, which is a number of ACK packets received by the communication device, and a number of retransmission request packets, which is a number of packets requested to be retransmitted in packets transmitted from the communication device, based on information on the ACK and the SACK;
• and
• changing a method for measuring the loss rate depending on a relation among the number of transmission packets, the number of retransmission request packets, and the number of ACK packets.

A packet loss rate measuring method, comprising:

• measuring a loss rate of a packet transmitted from a communication device to a network;
• measuring a number of transmission packets, which is a number of packets transmitted from the communication device to the network;
• measuring a loss rate of a packet transmitted from the communication device to the network in a predetermined period based on the number of transmission packets and information on the SACK and an ACK included in an ACK packet received by the communication device via the networks;
• controlling a band for transmitting a packet from the communication device to the network in response to a change in the loss rate;
• and
• transmitting a packet by the communication device in accordance with the controlled band.