METHOD AND DEVICE FOR EFFICIENTLY RETRANSMITTING PACKETS IN WIRED/WIRELESS NETWORK

• US 20080082891A1
• Filed: 07/09/2007
• Published: 04/03/2008
• Est. Priority Date: 09/29/2006
• Status: Active Grant

• Current Assignee: Electronics and Telecommunications Research Institute
• Original Assignee: Electronics and Telecommunications Research Institute
• Inventors: Doh, Yoonmee, Kim, Sun Joong, Pyo, Cheol Sig, Park, Noseong
• Granted Patent: US 8,042,016 B2
• Time in Patent Office: Days
• US Class Current: 714/749
• CPC Class Codes: H04L 1/1621 Group acknowledgement, i.e. the acknowledgement message defining a range of identifiers, e.g. of sequence numbers
• CPC Class Codes: H04L 1/1829 Arrangements specially adapted for the receiver end

Abstract

Provided a method and device for efficiently retransmitting packets of which transmissions failed in wired/wireless network including detecting continuity by detecting whether or not a sequence ID of a received packet is continuous with a start sequence ID or an end sequence ID of packets included in reception blocks which are generated in advance of the received packet; depending on the result of the detection, manipulating reception blocks to renew or delete the reception blocks or generate a new reception block by using the sequence ID of the received packet; and transmitting an EBN (Explicit Block NACK) for requesting retransmission of lost packets in units of a block when discontinuity is detected.

Claims

1. A packet retransmission request method used in a reception apparatus in a wired/wireless network, the method comprising:

detecting continuity by detecting whether or not a sequence ID of a received packet is continuous with a start sequence ID or an end sequence ID of packets included in reception blocks which are generated in advance of the received packet;

depending on the result of the detection, manipulating reception blocks to be renewed or deleted or generating a new reception block by using the sequence ID of the received packet; and

transmitting an EBN (Explicit Block NACK) for requesting retransmission of lost packets in units of a block when discontinuity is detected.

2. The method of claim 1, wherein the EBN comprises a start sequence ID and an end sequence ID of the lost packets.

3. The method of claim 1, wherein the reception block comprises a start sequence ID and an end sequence ID of packets which are continuously received without failure and the number of retransmission requests made by means of the EBN.

4. The method of claim 1, wherein when the sequence ID of the received packet is continuous with the start sequence ID or the end sequence ID of the reception blocks, in the manipulating of the reception blocks, the reception blocks are renewed by using the sequence ID of the received packet.

5. The method of claim 1,

wherein when the sequence ID of the received packet is discontinuous with the start sequence ID or the end sequence ID of the reception blocks,

in the manipulating of the reception blocks, a new reception block is generated, and

in the transmitting of an EBN, an EBN for requesting retransmission of packets between a reception block immediately prior to the new reception block and the new reception block is generated.

6. The method of claim 5, wherein, when an s-bit representing that a packet including the s-bit has the earliest sequence ID from among packets that can be transmitted by a transmission apparatus is set in the received packet, retransmission is not requested.

7. The method of claim 1,

wherein when the sequence ID of the received packet is discontinuous with an end sequence ID of a first reception block and is continuous with a start sequence ID of a second reception block which is disposed immediately after the first reception block,

in the manipulating of the reception blocks, the second reception block is renewed, and

in the transmitting an EBN, an EBN for requesting retransmission of packets between the first reception block and the renewed second reception block is transmitted.

8. The method of claim 1, wherein, in the manipulating of the reception blocks, when a timer which is set when the EBN is transmitted is expired, the reception block which transmitted the EBN is determined to exist in order to request a retransmission or terminate the retransmission operation.

9. The method of claim 1, wherein, when the number of retransmission requests made by means of the EBN exceeds a predetermined critical value, retransmission is not required, and the reception block is immediately renewed or deleted.

10. The method of claim 1, wherein the reception apparatus manages reception blocks corresponding to only the recent packets corresponding to the number of packets that are stored to be retransmitted by a transmission apparatus, and deletes reception blocks having sequence IDs less than a number obtained by subtracting the number of packets from a sequence ID of the most recent packet.

11. A packet retransmission method used in a transmission apparatus in a wired/wireless network, the method comprising:

sequentially transmitting packets to be transmitted while increasing sequence IDs of the packets by 1 without waiting for ACK (acknowledgement message) signals from a reception apparatus in a wired/wireless network; and

retransmitting packets having sequence IDs included in the EBN when an EBN for requesting retransmission of lost packets in units of a block is received from the reception apparatus.

12. The method of claim 11, wherein, in the retransmitting, when the transmission apparatus stores only parts of the packets which are requested to be retransmitted, an s-bit representing that a packet including the s-bit has the earliest sequence ID from among packets that can be transmitted is set in a packet having the earliest sequence ID from among the parts of the packets, and the packet in which the s-bit is set is transmitted.

13. The method of claim 11, wherein the number of packets which are to be stored by the transmission apparatus in order to be retransmitted is determined by using a probability value which is set by a user as an objective with respect to a probability of existence of the packets in the transmission apparatus that are requested to be retransmitted by the reception apparatus, and a probability value of failure of transmission when a packet is transmitted.

14. A packet retransmission request device used in a reception apparatus in a wired/wireless network, the device comprising:

a continuity detection unit detecting that a sequence ID of a received packet is continuous with a start sequence ID or an end sequence ID of packets included in existing reception blocks;

a reception block manipulation unit renewing or deleting the reception blocks or generating a new reception block by using the sequence ID of the received packet depending on the result of the detection; and

an EBN transmission unit transmitting an EBN for requesting retransmission of lost packets in units of a block when discontinuity is detected.

15. The device of claim 14, wherein the EBN comprises a start sequence ID and an end sequence ID of the lost packets.

16. The device of claim 14, wherein the reception block comprises a start sequence ID and an end sequence ID of packets which are continuously received without failure and the number of retransmission requests made by means of the EBN.

17. The device of claim 14, wherein, when the sequence ID of the received packet is continuous with the start sequence ID or the end sequence ID of the reception blocks, the reception block manipulation unit renews the reception blocks by using the sequence ID of the received packet.

18. The device of claim 14,

wherein when the sequence ID of the received packet is discontinuous with the start sequence ID or the end sequence ID of the reception blocks,

the reception block manipulation unit generates a new reception block, and

the EBN transmission unit transmits an EBN for requesting retransmission of packets between a reception block immediately prior to the new reception block and the new reception block.

19. The device of claim 18, wherein, when an s-bit representing that a packet including the s-bit has the earliest sequence ID from among packets that can be transmitted by a transmission apparatus is set in the received packet, retransmission is not requested.

20. The device of claim 14,

wherein when the sequence ID of the received packet is discontinuous with an end sequence ID of a first reception block and is continuous with a start sequence ID of a second reception block which is disposed immediately after the first reception block,

the reception block manipulation unit renews the second reception block, and

the EBN transmission unit transmits an EBN for requesting retransmission of packets between the first reception block and the renewed second reception block.

21. The device of claim 14, wherein, when a timer which is set when the EBN is transmitted is expired, the reception block manipulation unit detects whether or not the reception block which transmitted the EBN still exists in order to request a retransmission or terminate the retransmission operation.

22. The device of claim 14, wherein, when the number of retransmission requests made by means of the EBN exceeds a predetermined critical value, retransmission is not required, and the reception block is immediately renewed or deleted.

23. The device of claim 14, wherein the reception block manipulation unit manages reception blocks corresponding to only the recent packets corresponding to the number of packets that are stored to be transmitted by a transmission apparatus, and deletes reception blocks having sequence IDs less than a number obtained by subtracting the number of packets from a sequence ID of the most recent packet.

24. A packet retransmission device used in a transmission apparatus in a wired/wireless network, the device comprising:

a sequential transmission unit sequentially transmitting packets while increasing sequence IDs of the packets by 1 without waiting for ACK signals from a reception apparatus in a wired/wireless network; and

a retransmission unit retransmitting packets having sequence IDs included in the EBN when an EBN for requesting retransmission of lost packets in units of a block is received from the reception apparatus.

25. The device of claim 24, wherein, when the transmission apparatus stores only parts of the packets which are requested to be retransmitted, the retransmission unit sets an s-bit representing that a packet having the s-bit has the earliest sequence ID from among packets that can be transmitted in a packet and transmits the packet in which the s-bit is set.

26. The device of claim 24, wherein the number of packets which are to be stored by the transmission apparatus in order to be retransmitted is determined by using a probability value which is set by a user as an objective with respect to a probability of existence of the packets in the transmission apparatus that are requested to be retransmitted by the reception apparatus, and a probability value of failure of transmission when a packet is transmitted.