System for Communicating Data in xDSL Using Data Retransmission

• US 20080063007A1
• Filed: 09/12/2007
• Published: 03/13/2008
• Est. Priority Date: 09/13/2006
• Status: Active Grant

• Current Assignee: Avago Technologies International Sales Pte Limited (Broadcom, Inc.)
• Original Assignee: Broadcom Corporation (Broadcom, Inc.)
• Inventors: Christiaens, Benoit, Peeters, Miguel, Cassiers, Raphael
• Granted Patent: US 8,381,055 B2
• Time in Patent Office: Days
• US Class Current: 370/458
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/1614 using bitmaps
• CPC Class Codes: H04L 1/1642 Formats specially adapted for sequence numbers
• CPC Class Codes: H04L 1/1812 Hybrid protocols; Hybrid automatic repeat request [HARQ]
• CPC Class Codes: H04L 1/1867 Arrangements specially adapted for the transmitter end
• CPC Class Codes: H04L 1/1874 Buffer management

Abstract

An apparatus for transmitting data in an xDSL system is disclosed. In an exemplary embodiment, the apparatus comprises a transmitter that sends data over an xDSL system in the form of a data transmission unit (DTU), the transmitter having physical media specific—transmission convergence (PMS-TC) communication sublayer. The apparatus may further include a retransmission unit that is implemented in the PMS-TC sublayer. The retransmission unit may include a retransmission buffer that stores and indexes transmitted DTUs in retransmit containers. The retransmit container may be defined as a time slot corresponding to a sent DTU, wherein the retransmission unit is configured to respond to a retransmission request indicating which stored DTU should be retransmitted. The stored DTU to be retransmitted may be identified by its corresponding retransmit container.

Claims

1. A apparatus for transmitting data in an xDSL system, comprising:

a transmitter that sends data over an xDSL system in the form of a data transmission unit (DTU), the transmitter having physical media specific—

transmission convergence (PMS-TC) communication sublayer; and

a retransmission unit that is implemented in the PMS-TC sublayer, the retransmission unit including a retransmission buffer that stores and indexes transmitted DTUs in retransmit containers, the retransmit container being defined as a time slot corresponding to a sent DTU;

wherein the retransmission unit is configured to respond to a retransmission request indicating which stored DTU should be retransmitted, wherein the stored DTU to be retransmitted is identified by its corresponding retransmit container.

2. The apparatus of claim 1, wherein the DTU to be retransmitted is further identified by a unique sequence identification number (SID) that is added to the DTU in the PMS-TC sublayer.

3. The apparatus of claim 1, further including a forward error correction unit coupled to the retransmission buffer for encoding the DTUs.

4. The apparatus of claim 3, wherein the forward error correction unit uses Reed-Solomon encoding.

5. The apparatus of claim 3, wherein the DTU is defined as a group of n consecutive code words.

6. The apparatus of claim 1, further comprising a retransmission control channel coupled to the PMS-TC sublayer wherein the retransmission control channel is configured to receive the retransmission request from a receiver and retransmit the requested stored DTU.

7. A apparatus for transmitting data in an xDSL system, comprising:

a transmitter that sends data over an xDSL system in the form of a data transmission unit (DTU), the transmitter having a transport protocol specific transmission convergence (TPS-TC) communication sublayer and a physical media specific transmission convergence (PMS-TC) communication sublayer;

a retransmission layer disposed between the TPS-TC and PMS-TC communication sublayers; and

a retransmission unit that is implemented in the retransmission sublayer, the retransmission unit including a retransmission buffer that stores and indexes transmitted DTUs in retransmit containers, the retransmit container being defined as a time slot corresponding to a sent DTU;

wherein the retransmission unit is configured to respond to a retransmission request indicating which stored DTU should be retransmitted, wherein the stored DTU to be retransmitted is identified by its corresponding retransmit container.

8. The apparatus of claim 7, wherein the DTU to be retransmitted is further identified by a unique sequence identification number (SID) that is added to the DTU in the retransmission sublayer.

9. The apparatus of claim 7, wherein the DTU is defined as a fixed number of bytes from an asynchronous transfer mode (ATM) cell.

10. The apparatus of claim 7, wherein the DTU is defined as a fixed number of bytes from a packet transfer mode (PTM) fragment.

11. The apparatus of claim 7, further comprising a retransmission control channel coupled to the PMS-TC sublayer wherein the retransmission control channel is configured to receive the retransmission request from a receiver and retransmit the requested stored DTU.

12. A apparatus for transmitting data in an xDSL system, comprising:

a transmitter that sends data over an xDSL system in the form of a data transmission unit (DTU), the transmitter having a physical media specific transmission convergence (PMS-TC) communication sublayer and a physical media dependent (PMD) communication sublayer;

a retransmission layer disposed between the PMS-TC and PMD communication sublayers; and

a retransmission unit that is implemented in the retransmission sublayer, the retransmission unit including a retransmission buffer that stores and indexes transmitted DTUs in retransmit containers, the retransmit container being defined as a time slot corresponding to a sent DTU;

wherein the retransmission unit is configured to respond to a retransmission request indicating which stored DTU should be retransmitted, wherein the stored DTU to be retransmitted is identified by its corresponding retransmit container.

13. The apparatus of claim 12, wherein the DTU to be retransmitted is further identified by a unique sequence identification number (SID) that is added to the DTU in the retransmission sublayer.

14. The apparatus of claim 12, wherein the DTU is defined as a group of L bits mapped in a single DMT symbol.