RETRANSMISSION SCHEME FOR COMMUNICATION SYSTEMS

• US 20090089641A1
• Filed: 10/02/2008
• Published: 04/02/2009
• Est. Priority Date: 10/02/2007
• Status: Active Grant

• Current Assignee: Maxlinear Incorporated
• Original Assignee: Infineon Technologies AG
• Inventors: Schoppmeier, Dietmar, Heise, Bernd, Schedelbeck, Gert, Thyagarajan, Umashankar
• Granted Patent: US 8,788,901 B2
• Time in Patent Office: Days
• US Class Current: 714/748
• CPC Class Codes: H04L 1/0083 Formatting with frames or packets; Protocol or part of protocol for error control
• 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 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• 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 1/1874 Buffer management
• 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 2001/0098 Unequal error protection
• CPC Class Codes: H04L 69/324 in the data link layer [OSI layer 2], e.g. HDLC
• CPC Class Codes: H04L 69/40 for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection management of faults, events, alarms or notifications in data switching networks H04L41/06

Abstract

One embodiment relates to a method of communicating data between a transmitter and a receiver of a communication system. In this method, a payload data stream is received from a network interface layer. The payload data stream includes data units eligible for retransmission and data units non-eligible for retransmission. These data units are grouped into containers, where a container is associated with a container identifier that distinguishes the container from other containers. The containers are grouped into data transmission units, where a data transmission unit includes at least one container along with redundancy information that facilitates error detection for that data transmission unit. The data transmission units are transmitted to the receiver as a transmission data stream. Other methods and systems are also disclosed.

Claims

1. A method of communicating data between a transmitter and a receiver of a communication system, comprising:

receiving a payload data stream comprising data units eligible for retransmission (EL) and data units non-eligible for retransmission (NEL);

grouping the data units into a container stream comprising a series of containers, where a container is associated with a container identifier that distinguishes the container from other containers;

incorporating the container stream into a transmission data stream transmitted to a receiver;

receiving a retransmission request from the receiver, the retransmission request specifying an original container in the transmission data stream that was received having corrupted data; and

generating a retransmission container in response to the retransmission request, the retransmission container including the data units eligible for retransmission in the original container.

2. The method of claim 1, where the retransmission container also includes new data not included in the original container.

3. The method of claim 2, where data units non-eligible for retransmission in the original container are not included in the retransmission container.

4. The method of claim 3, where the retransmission container has the same length as the original container, and where the position of new data in the retransmission container corresponds to the position of the data units non-eligible for retransmission in the original container.

5. The method of claim 1, further comprising:

fragmenting a data unit into at least two fragments prior to grouping the data units into the container stream.

6. The method of claim 5, where a single fragment is split between at least two containers and where the single fragment is associated with a header specifying how a boundary of the single fragment aligns with respect to the at least two containers.

7. The method of claim 1, where the payload data stream is received at a network interface layer is a data link layer or a physical layer of a network stack.

8. The method of claim 1, where each data unit includes only a single complete Ethernet packet, only a single complete Asynchronous Transfer Mode (ATM) cell, or a single complete Ethernet fragment.

9. The method of claim 1, where containers are grouped so that each container has an approximately constant number of data units.

10. The method of claim 9, where the approximately constant number of data units for each container can be changed dynamically using a reconfiguration protocol.

11. The method of claim 1, where containers are grouped so that data units eligible for retransmission are packed into a container having a container length up to some maximum number of data units, and where data units non-eligible for retransmission are packed into separate containers from the data units eligible for retransmission.

12. A transmitter, comprising:

a network interface layer adapted to receive a payload data stream;

a container controller adapted to group data units of the payload data stream into containers;

a data transmission controller adapted to group the containers into data transmission units, where a data transmission unit includes at least one container; and

a transmission controller that mixes un-transmitted data transmission units with data transmission units to be retransmitted, thereby generating a transmission data stream suitable for transmission over a transmission medium.

13. The transmitter of claim 12, where a data transmission unit includes redundancy information that facilitates error detection for the data transmission unit.

14. The transmitter of claim 12, where the container controller is adapted to append a container header to each container, the container header comprising:

a retransmission eligibility field; and

a container identifier that distinguishes the containers from one another.

15. The transmitter of claim 12, further comprising:

a fragment controller adapted to fragment a data unit into at least two fragments, where a fragment is associated with a fragment header that is different from that of other fragments.

16. The transmitter of claim 15, where the fragment header comprises:

a fragment sequence identifier; and

an end_of_fragment (EF) field that indicates how a fragment boundary associated with the fragment relates to a container boundary of a container in which the fragment at least partially resides.

17. The transmitter of claim 12, further comprising:

a retransmission buffer adapted to store the eligible data units from the transmission data stream after the eligible data units are transmitted.

18. The transmitter of claim 17, further comprising:

a retransmission controller adapted to analyze a retransmission request and determine which eligible data units stored in the retransmission buffer are to be re-transmitted over the transmission medium.

19. The transmitter of claim 18, where the retransmission controller uses a table-lookup to correlate a container identification number obtained from the retransmission request with the eligible data units stored in the retransmission buffer.

20. The transmitter of claim 17, where the retransmission buffer is adapted to store embedded overhead channel data associated with eligible data units of a container.

21. A communication system, comprising:

a transmitter adapted to transmit data transmission units over a transmission medium, the data transmission units including one or more containers associated with respective container identifiers, and the containers including data units eligible for retransmission and data units non-eligible for retransmission;

a receiver adapted to receive the data transmission units and transmit a retransmission request that specifies uncorrectable data received in at least one of the containers.

22. The communication system of claim 21, where the retransmission request includes a container identifier that corresponds to a container associated with the uncorrectable data.

23. The communication system of claim 22, where the retransmission request includes upstream payload data piggybacked onto the container identifier.

24. The communication system of claim 22, where the transmitter further comprises:

a retransmission controller adapted to retrieve a previously transmitted container from a retransmission buffer in response to the retransmission request;

the previously transmitted container associated with the container identifier.

25. The communication system of claim 24, where the previously transmitted container includes at least one previously transmitted data unit eligible for retransmission and at least one previously transmitted data unit non-eligible for retransmission.

26. The communication system of claim 25, where the retransmission controller is further adapted to generate a retransmission container that includes the at least one previously transmitted data unit eligible for retransmission along with new data instead of the at least one previously transmitted data unit non-eligible for retransmission.

27. The communication system of claim 22, where the transmitter and receiver synchronously update a count value representative of the container identifier.

28. A method of communication, comprising:

transmitting a stream of data units over a transmission medium, where the data units are categorized according to at least three levels of retransmission eligibility;

receiving a retransmission request specifying whether at least one data unit in the stream of data units was received having corrupted data;

retransmitting the at least one corrupted data unit in a first manner if the at least one corrupted data unit has the first level of retransmission eligibility; and

retransmitting the at least one corrupted data unit in a second manner if the at least one corrupted data unit has the second level of retransmission eligibility, the second manner differing from the first manner.

29. A receiver, comprising:

a data reception controller adapted to analyze whether received data transmission units includes corrupted data based on redundancy information in the received data transmission units;

a container controller adapted to correlate the corrupted data with an original container included in the received data transmission units; and

a retransmission controller adapted to generate a retransmission request that specifies the original container that included the corrupted data.

30. The receiver of claim 29, where the receiver is further adapted to receive a retransmission container that includes data units eligible for retransmission in the original container.

31. The receiver of claim 30, where the retransmission container also includes new data not included in the original container.

32. The receiver of claim 31, where data units non-eligible for retransmission in the original container are not included in the retransmission container.

33. A transceiver for retransmission, comprising:

a receiver adapted to receive a stream of data transmission units having containers optionally embedded therein, a data transmission unit including redundancy information that facilitates error detection for that data transmission unit; and

a controller having knowledge of whether the data transmission units have containers embedded therein and adapted to detect a corrupted data transmission unit in the stream based on the redundancy information; and

a transmitter;

where if containers are embedded in the stream, the transmitted is adapted to transmit a retransmission request that specifies the container associated with the corrupted data transmission unit;

but where if containers are not embedded in the stream of data transmission units, the transmitter is adapted to transmit a retransmission request that specifies the corrupted data transmission unit.