Transmission order based selective repeat data transmission error recovery system and method
First Claim
1. An error recovery system for use in a data communication system in which a sender station transmits a plurality of information packets, each of the information packets having an associated sequential number to a receiver station, comprising:
- means for transmitting said information packets;
means for detecting if said information packets have been transmitted without error;
means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets;
retransmission control means, responsive to said means for detecting if said information packets have been transmitted without error and said means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets, for identifying any of said information packets which have had an error in transmission and were transmitted by said means for transmitting information packets earlier in time than one of said information packets which has been transmitted without error and for providing any such information packet to said means for transmitting information packets for retransmission; and
wherein said means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets comprises means for placing an identification of a transmitted information packet at an end of a list at the time of transmission of the transmitted information packet.
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0 Petitions
Accused Products
Abstract
An error recovery system and method for use in a data communication system in which a sender station transmits information packets with sequentially numbered information to a receiver station. The system includes selective retransmission of information packets which have had errors in transmission based on the order of transmission of information packets independent of the sequential (sequence) number of the information packets. A list, such as a linked list having a beginning and an end, is provided and, at the time of transmission of information packets, an identification of the transmitted information packet is placed at the end of the list. A status packet is provided by the receiver station to the sender station which identifies the sequential number of information packets which have been correctly received. Any information packets which have not been acknowledged as correctly received are retransmitted only if such packet was transmitted earlier in time than an information packet which has been acknowledged as correctly received as indicated by the position of the information packets in the list. The receiver station detects the presence of gaps and transmits a status packet to the sender station either responsive to a request from the sender station or responsive to detection of a gap.
268 Citations
17 Claims
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1. An error recovery system for use in a data communication system in which a sender station transmits a plurality of information packets, each of the information packets having an associated sequential number to a receiver station, comprising:
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means for transmitting said information packets; means for detecting if said information packets have been transmitted without error; means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets; retransmission control means, responsive to said means for detecting if said information packets have been transmitted without error and said means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets, for identifying any of said information packets which have had an error in transmission and were transmitted by said means for transmitting information packets earlier in time than one of said information packets which has been transmitted without error and for providing any such information packet to said means for transmitting information packets for retransmission; and wherein said means for determining an order in time of transmission of said information packets independent of the associated sequential numbers of said plurality of information packets comprises means for placing an identification of a transmitted information packet at an end of a list at the time of transmission of the transmitted information packet. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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8. A sender station for use in a data communication system in which the sender station transmits a plurality of information packets, each of the information packets having an associated sequential number to a receiver station, comprising:
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a transmitter operatively connected to said data communication system; a linked list having a beginning and an end; means for placing in said linked list at said end thereof the associated sequential number of each information packet transmitted by said transmitter as each information packet is transmitted by said transmitter so that said link list provides a transmission order list of the associated sequential numbers of said information packets. - View Dependent Claims (9)
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10. An error recovery method for a data communication system in which a sender station transmits a plurality of information packets, each of the information packets having an associated sequential number, to a receiver station, comprising the steps of:
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transmitting one of said plurality of information packets to the receiver station; detecting if the transmitted information packet has been transmitted without error; determining an order in time of transmission of the plurality of information packets independent of the associated sequential numbers of the information packets; and retransmitting any information packets which have had an error in transmission which were transmitted earlier in time than an information packet which has been transmitted without error; and wherein said step of detecting if the information packet has been transmitted without error comprises the steps of; detecting a gap in the associated numbers of correctly received information packets; and transmitting to the sender station a status packet containing acknowledgment of correctly received information packets responsive to said step of detecting a gap in the associated sequential numbers of correctly received information packets. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
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Specification