Network access device and method for protecting subscriber line communications

• US 7,760,624 B1
• Filed: 03/08/2005
• Issued: 07/20/2010
• Est. Priority Date: 03/08/2005
• Status: Active Grant

• Current Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Original Assignee: ADTRAN Incorporated (ADTRAN Holdings, Inc.)
• Inventors: Goodson, Richard L., Wilson, Arlynn W., Schneider, Kevin W.
• Primary Examiner(s): Mattis; Jason E
• Application Number:
  US11/074,918
• Time in Patent Office: 1,960 Days
• Field of Search: 370/217, 370/219, 370/225, 370/228
• US Class Current: 370/228
• CPC Class Codes: H04L 12/2865 Logical combinations
• CPC Class Codes: H04L 12/2867 Physical combinations
• CPC Class Codes: H04L 45/00 Routing or path finding of packets in data switching networks routing or path finding in wireless networks H04W40/00
• CPC Class Codes: H04L 69/14 Multichannel or multilink protocols
• 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
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data

Abstract

A network access device comprises a first line card, a second line card, and logic. The first line card has a first transceiver coupled to a first subscriber line, and the second line card has a second transceiver coupled to a second subscriber line. The logic is configured to switch communication from the first subscriber line to the second subscriber line in response to a detection of an error condition for communication occurring over the first subscriber line.

Claims

1. A network access device, comprising:

a plurality of line cards coupled to a plurality of subscriber lines, each of the subscriber lines coupled to communication equipment for servicing a customer, the communication equipment at a single customer premises, each of the line cards having a transceiver coupled to a respective one of the subscriber lines;

a line card having a backup transceiver coupled to a backup subscriber line for backing up each of the plurality of subscriber lines, the backup subscriber line coupled to the communication equipment for servicing the customer; and

logic configured to switch communication from one of the subscriber lines to the backup subscriber line in response to a detection of an error condition for the communication occurring over the one subscriber line, wherein the line card having the backup transceiver is coupled to the communication equipment for servicing the customer via a single subscriber line, wherein each of the plurality of line cards is coupled to the communication equipment for servicing the customer via a single respective subscriber line, wherein the backup subscriber line extends from the network access device to the communication equipment for servicing the customer thereby providing a first data path from the network access device to the communication equipment, wherein the one subscriber line extends from the network access device to the communication equipment servicing the customer thereby providing a second data path from the network access device to the communication equipment, and wherein the first data path is separate from the second data path.

2. The device of claim 1, further comprising a controller card having a multiplexer, the multiplexer coupled to each of the line card having the backup transceiver and the plurality of line cards.

3. The device of claim 2, wherein the plurality of line cards have a plurality of transceivers, and wherein the multiplexer is configured to separately transmit a plurality of data streams to the plurality of transceivers, each of the plurality of transceivers configured to receive a respective one of the plurality of data streams.

4. The device of claim 2, further comprising a chassis, wherein the plurality of line cards, the line card having the backup transceiver, and the controller card are each inserted into the chassis.

5. The device of claim 4, wherein the chassis has a backplane that couples the controller card to the plurality of line cards and line card having the backup transceiver.

6. A network access device, comprising:

a plurality of line cards coupled to a plurality of primary subscriber lines extending to a single customer premises, each of the line cards having a primary transceiver coupled to a respective one of the primary subscriber lines, each of the primary subscriber lines coupled to communication equipment at the customer premises;

a line card having a backup transceiver coupled to a backup subscriber line for backing up the primary subscriber lines, the backup subscriber line coupled to the communication equipment at the customer premises; and

logic configured to demultiplex a high speed data stream into a plurality of lower speed data streams and to selectively switch one of the lower speed data streams between one of the primary subscriber lines and the backup subscriber line based on a status of communication occurring over the one primary subscriber line, wherein the line card having the backup transceiver is coupled to the communication equipment at the customer premises via a single subscriber line, wherein each of the plurality of line cards is coupled to the communication equipment at the customer premises via a single respective subscriber line, wherein the backup subscriber line extends from the network access device to the communication equipment at the customer premises thereby providing a first data path from the network access device to the communication equipment, wherein the one primary subscriber line extends from the network access device to the communication equipment at the customer premises thereby providing a second data path from the network access device to the communication equipment, and wherein the first data path is separate from the second data path.

7. The network access device of claim 6, wherein the logic is mounted on a printed circuit board separate from the plurality of line cards and the line card having the backup transceiver.

8. The network access device of claim 7, further comprising a chassis having a backplane, wherein the first line card, the second line card, and the printed circuit board are interfaced with the backplane.

9. A network access method, comprising the steps of:

providing a plurality of line cards at a network facility, each of the line cards having a respective transceiver, the plurality of line cards including at least a first line card, a second line card, and a third line card;

coupling each of the first, second, and third line cards to a respective one of a plurality of subscriber lines, each of the plurality of subscriber lines extending from the network facility to a single customer premises;

communicating data between the first and second line cards and communication equipment at the customer premises;

detecting an error condition associated with communication occurring over one of the subscriber lines;

ensuring that each of the plurality of line cards is coupled to the communication equipment via a single respective subscriber line; and

switching communication from the one subscriber line to the subscriber line coupled to the third line card in response to the detecting step, wherein the one subscriber line and the subscriber line coupled to the third line card provide separate data paths from the network facility to the customer premises.

10. The method of claim 9, further comprising the step of communicating, via the each of the plurality of subscriber lines, data destined for communication equipment at the same customer premises.