Retransmission scheme in wireless computer networks

• US 6,574,668 B1
• Filed: 07/12/2000
• Issued: 06/03/2003
• Est. Priority Date: 01/25/2000
• Status: Expired due to Term

• Current Assignee: Cirrus Logic Incorporated
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Gubbi, Rajugopal R., Sebastian, Donia
• Primary Examiner(s): Burgess, Glenton B.
• Assistant Examiner(s): Kupstas, Tod
• Application Number:
  US09/614,928
• Time in Patent Office: 1,056 Days
• Field of Search: 709/237, 709/243, 709/244, 709/245, 709/231, 709/232, 709/233, 709/236
• US Class Current: 709/237
• CPC Class Codes: H04L 1/1614 using bitmaps
• CPC Class Codes: H04L 1/1809 Selective-repeat protocols
• CPC Class Codes: H04L 1/1832 Details of sliding window management
• CPC Class Codes: H04L 1/1838 for semi-reliable protocols, e.g. for less sensitive applications such as streaming video buffer level management for video bitstream receiver H04N21/44004
• CPC Class Codes: H04L 1/1877 for semi-reliable protocols, e.g. for less sensitive applications like streaming video buffer level management for video bitstream control arrangements H04N21/44004
• CPC Class Codes: H04L 1/188 Time-out mechanisms
• CPC Class Codes: H04L 1/1887 Scheduling and prioritising arrangements
• CPC Class Codes: H04L 2001/0093 Point-to-multipoint

Abstract

Data is transmitted over a computer network from a source network component to one or more destination network components. Thereafter, one or more acknowledgements are transmitted from one of the destination network components to the source network component; and different data, which may include retransmissions, from the previously transmitted data is transmitted from the source network component to the one or more destination network components. A negative acknowledgement message from the destination network component may be transmitted to the source network component upon a failure to receive one or more of the transmitted data packets, the negative acknowledgment including packet identifications of said one or more data packets. Then data packets identified by the identifications received in a negative acknowledgement may be retransmitted before transmitting other packets. The negative acknowledgements thus indicate failed receipt of data. Positive acknowledgements indicate successful receipt of data.

Claims

1. A method of retransmission of data in computer networks comprising:

transmitting a first group of data packets from a plurality of data packets, over a computer network from a source network component, to one or more destination network components, wherein the data is transmitted as sequentially identified packets within a network frame;

transmitting one or more acknowledgements from a destination network component to the source network component, the acknowledgements comprising;

positive acknowledgements transmitted upon successful receipt of one or more of the transmitted data packets and including the packet identifications of said one or more successfully received data packets, and sequential identifications of all successfully received data packets from the first negatively acknowledged packet in the last negative acknowledgement to the last successfully received packet; and

negative acknowledgements transmitted upon failed receipt of one or more of the transmitted data packets, the acknowledgments including the packet identifications of said one or more data packets that failed reception; and

transmitting a second group of data packets comprised of previously transmitted data, which includes one or more of the first group of data packets, and newly transmitted data, which includes one or more new data packets from the plurality of data packets, from the source network component to one or more destination network components upon failure to receive said one or more acknowledgements from said destination network component.

2. The method of claim 1 wherein the one or more of the first group of packets transmitted in the second group of packets comprises previously transmitted data for which a positive acknowledgement has not been received prior to the expiration of a specified timeout period.

3. The method of claim 1 wherein a portion of bandwidth is reserved through negotiations between source and destination network components for each data stream transmitted.

4. The method of claim 1 wherein said acknowledgements comprise a window of packets and the status of receipt of each of the packets within the window.

5. The method of claim 4 wherein the window of packets comprises a sequence number of the earliest packet that has not been received.

6. The method of claim 5 wherein the window further comprises a sequence number of the most recent packet that has been received correctly.

7. The method of claim 6 wherein the number of packets transmitted within a network frame can be dynamically negotiated for each data stream transmitted between two network components.

8. The method of claim 4 wherein the status of the packets in the window is indicated by a bit map.

9. The method of claim 8 wherein the positive acknowledgements are indicated in the bitmap by a bit of a first value and the negative acknowledgments are indicated by bit of a second value.

10. The method of claim 9 wherein the source network component re-transmits the packets with identifications included in the negative acknowledgement.

11. The method of claim 10 wherein the source network component maintains an index window of sequential packets available for retransmission.

12. The method of claim 11 wherein the retransmission index window dynamically spans from the last non-acknowledged packet to the last transmitted packet in the sequence.

13. The method of claim 1 wherein the packets to be retransmitted are transmitted before any new packets.

14. The method of claim 13 wherein the number of times a packet is retransmitted before dropping it is dynamically negotiated for each stream of data transmitted between two or more network components.

15. The method of claim 13 wherein one or more of the packets are re-transmitted one or more times within a one network frame.

16. The method of claim 13 wherein all of the packets to be re-transmitted are transmitted at least once before transmitting any new packets within a network frame.

17. The method of claim 1 further comprising a modulated signal embodying one or more computer-readable symbols, which when organized in a computer platform, allow said platform to acknowledge reception of stream data in accordance therewith, said symbols containing one or more of the following fields:

a packet type, a stream ID, the length of acknowledgement message, a beginning sequence number, an ending sequence number, and the status of each packet between the beginning sequence number and the ending sequence number.