SYSTEMS AND METHODS FOR REGULATING DELAY BETWEEN NETWORK INTERFACES

• US 20100070817A1
• Filed: 08/14/2009
• Published: 03/18/2010
• Est. Priority Date: 09/12/2008
• Status: Active Grant

• Current Assignee: Infineon Technologies AG
• Original Assignee: Infineon Technologies AG
• Inventors: Heise, Bernd
• Granted Patent: US 8,910,006 B2
• Time in Patent Office: Days
• US Class Current: 714/749
• CPC Class Codes: H04J 3/0664 unidirectional timestamps
• CPC Class Codes: H04L 1/1664 the supervisory signal being transmitted together with payload signals; piggybacking
• CPC Class Codes: H04L 1/1678 where the control information is for timing, e.g. time stamps
• CPC Class Codes: H04L 1/1825 Adaptation of specific ARQ protocol parameters according to transmission conditions
• CPC Class Codes: H04L 1/1841 Resequencing
• CPC Class Codes: H04L 1/188 Time-out mechanisms

Abstract

One embodiment relates to a method of processing data in a transmitter. In the method, a timestamp is generated for a data unit. The data unit is stored in a memory unit in the transmitter. The data unit is transmitted from the transmitter to a receiver. The transmitter waits up to a predetermined time measured with respect to the timestamp to receive an acknowledgement from the receiver. Based on whether the acknowledgement is received within the predetermined time, the transmitter selectively retransmits the data unit to the receiver. Other methods and systems are also disclosed.

Claims

1. A method of processing data in a transmitter, comprising:

generating a timestamp for a data unit;

storing the data unit in a memory unit in the transmitter;

initially transmitting the data unit from the transmitter to a receiver;

waiting up to a predetermined time measured with respect to the timestamp to receive an acknowledgement from the receiver;

based on whether the acknowledgement is received within the predetermined time, selectively retransmitting the data unit to the receiver.

2. The method of claim 1, further comprising:

monitoring a periodicity of repetitive electrical impulse noise; and

selecting the predetermined time based on the periodicity of repetitive electrical impulse noise.

3. The method of claim 1, further comprising:

if the acknowledgement is received, then removing the data unit from the memory unit.

4. The method of claim 3, further comprising:

if the data unit is retransmitted more than a predetermined number of times or if another predetermined time expires without receiving an acknowledgement, then removing the data unit from the memory unit.

5. The method of claim 1, where the timestamp corresponds to an anticipated time at which the transmitter expects the data unit to be transmitted to the receiver.

6. The method of claim 1, where initially transmitting the data unit comprises:

initially transmitting the data unit with a sequence number indicative of how the data unit relates sequentially to other data units transmitted from the transmitter to the receiver.

7. The method of claim 6, where retransmitting the data unit comprises:

retransmitting the data unit with the same sequence number as when the data unit is initially transmitted.

8. The method of claim 1, where initially transmitting the data unit comprises:

initially transmitting the data unit along with the timestamp to the receiver, where the timestamp relates to a time at which the data unit is initially transmitted.

9. The method of claim 8, where retransmitting the data unit comprises:

retransmitting the data unit along with a different timestamp to the receiver, where the different timestamp relates to a time at which the data unit is retransmitted.

10. A method of providing a regulated delay between a network layer of a transmitter and a corresponding network layer of a receiver, comprising:

synchronizing a time in the transmitter with a time in the receiver and synchronously incrementing the times thereafter;

generating a timestamp for a data unit in the transmitter;

storing the data unit in a retransmission memory unit in the transmitter;

transmitting the data unit along with the timestamp from the transmitter to the receiver;

receiving the data unit at the receiver; and

selectively forwarding the data unit to the network layer of the receiver based on whether a time as measured by the receiver has a predetermined relationship with the timestamp plus the regulated delay.

11. The method of claim 10, further comprising:

selectively transmitting an acknowledgement from the receiver to the transmitter based on whether the data unit was received correctly at the receiver.

12. The method of claim 11, further comprising:

monitoring whether a memory element in the receiver is full, the memory element adapted to store received data units; and

selectively disabling transmission of acknowledgements from the receiver to the transmitter based on whether the memory element is full, thereby limiting overflow of the memory element in the receiver.

13. The method of claim 10, further comprising:

waiting up to a predetermined time after transmitting the data unit to receive an acknowledgement from the receiver;

based on whether the acknowledgement is received within the predetermined time, selectively retransmitting the data unit to the receiver.

14. The method of claim 10, where the regulated delay comprises a maximum delay threshold.

15. The method of claim 14, where the data unit is forwarded to the network layer of the receiver if the time as measured by the receiver is approximately equal to the timestamp plus the maximum delay threshold.

16. The method of claim 10, where the regulated delay comprises a minimum delay threshold.

17. The method of claim 16, where the data unit is held in the receiver without being forwarded to the network layer of the receiver so long as the time as measured by the receiver is less than the timestamp plus the minimum delay threshold.

18. The method of claim 10, further comprising:

selectively transmitting a negative acknowledgement from the receiver to the transmitter based on whether the data unit has been received at the receiver with uncorrectable data;

retransmitting the data unit from the transmitter to the receiver in a subsequent data unit based on the negative acknowledgement.

19. The method of claim 10, where the data unit is transmitted as part of a data unit stream comprising a plurality of data units having respective sequence numbers, where the sequence numbers collectively establish a predetermined order for consecutive data units in the data unit stream.

20. The method of claim 19, further comprising:

selectively holding the data unit in the receiver without forwarding the data unit to the network layer of the receiver based on whether the sequence number of the data unit follows sequentially from another data unit in the data unit stream which has been received at the receiver.

21. The method of claim 20, further comprising:

forwarding the data unit to the network layer of the receiver if a predetermined time as measured from the timestamp expires, independent of whether the data unit follows sequentially from another data unit in the data unit stream which has been received at the receiver.

22. A communication device, comprising:

a timestamp controller adapted to generate timestamps for respective data units;

a retransmission memory unit adapted to store the data units;

a transmission unit adapted to transmit the data units from the communication device to a receiver;

an acknowledgement controller adapted to wait up to a predetermined time measured from the timestamp of a transmitted data unit to receive an acknowledgement from the receiver; and

a retransmission controller adapted to selectively retransmit the transmitted data unit to the receiver based on whether the acknowledgement is received within the predetermined time.

23. The communication device of claim 22, where the timestamp for a data unit is an anticipated time at which the transmitter expects the data unit to be transmitted.