Circuit to provide backup telephone service for a multiple service access system using a twisted pair

• US 6,868,060 B2
• Filed: 09/24/2001
• Issued: 03/15/2005
• Est. Priority Date: 12/31/1997
• Status: Expired due to Fees

• Current Assignee: AT&T Corporation (AT&T, Inc.)
• Original Assignee: AT&T Corporation (AT&T, Inc.)
• Inventors: Gerszberg, Irwin, Barzegar, Farhad, Treventi, Philip Andrew
• Primary Examiner(s): Ho, Duc
• Assistant Examiner(s): Nguyen, Phuongchau Ba
• Application Number:
  US09/960,310
• Publication Number:
  US 20020027927A1
• Time in Patent Office: 1,268 Days
• Field of Search: 370/216, 370/225, 370/228, 370/414, 370/237, 370/352, 370/395, 370/485, 379/93.08
• US Class Current: 370/228
• CPC Class Codes: H04M 3/005 Interface circuits for subscriber lines current supply H04M19/00 and subgroups; supervisory, monitoring or testing arrangements H04M3/22 and subgroups; in key telephone systems H04M9/006
• CPC Class Codes: H04M 3/12 Marking faulty circuits "busy"; Enabling equipment to disengage itself from faulty circuits ; Using redundant circuits; Response of a circuit, apparatus or system to an error
• CPC Class Codes: H04M 3/2209 for lines also used for data transmission
• CPC Class Codes: H04M 3/30 for subscriber's lines , for the local loop

Abstract

A system for providing a life line safety connection from a subscriber telephone in a multiple band communication network for customer premise equipment is disclosed. Whenever a failure is detected in any of the systems or components an alternate route through line cards that bypasses digital multiplexing circuits enables a subscriber telephone such as an analog telephone to communicate through plain old telephone lines to outside networks. In some embodiments switches are automatically triggered to activate the life line safety connection. Other embodiments use a selected frequency band for providing the life line safety connection. Failure in external network interfaces as well as in a subscriber server or in customer premise devices can be effectively bypassed by practicing these life line safety connection techniques.

Claims

1. A multiple access subscriber link providing telecommunications between customer premise equipment and external networks, comprising:

first external network interface facilities having non-dedicated time shared multiplexer components for processing broadband transmission of voice, data and/or signaling;

second external network interface facilities having multiple dedicated line cards for handling narrowband plain old telephone (POT) transmissions;

a subscriber server having interconnections with multiple customer premise devices;

a conductor wire pair with a remote end connected to said first and said second external network interface facilities, and with a local end connected to said subscriber server; and

a subscriber telephone having a safety life line connectable through the conductor wire pair to said second external network interface facilities for providing a backup communication link through said dedicated line cards in said second external network interface facilities when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment.

2. The subscriber link of claim 1 further comprising a switch for providing a safety life line bypassing components in said subscriber server when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment.

3.The subscriber link of claim 1 further comprising a switch for providing a safety life line bypassing multiplexer components in said first external network when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment.

3. The subscriber link of claim 1 further comprising an analog subscriber telephone using a first portion of a frequency spectrum of the multiple access subscriber link as a safety life line when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment.

5. The subscriber link of claim 1 which further includes a line monitor for triggering a switch to connect a safety life line to a line card when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment.

6. The subscriber link of claim 1 wherein said backup communication link through said dedicated line cards serves as a termination of an analog subscriber phone line as well as interfacing digital communications to a calling/called plain old telephone (POT) connection.

7. The subscriber link of claim 1 which further includes a subscriber analog telephone capable of pulse or DEMF dialing, and connectable to a safety life line.

4. The subscriber link of claim 4 wherein said analog subscriber telephone is permanently connected to a line card of said second external network interface facilities.

8. A multiple access subscriber link providing telecommunications between customer premise equipment and external networks, comprising:

first external network interface facilities having non-dedicated time shared multiplexer components for processing broadband transmission of voice, data and/or signaling;

second external network interface facilities having multiple dedicated line cards for handling narrowband plain old telephone (POT) transmissions;

a subscriber server having interconnections with multiple customer premise devices;

a conductor wire pair with a remote end connected to said first and said second external network interface facilities, and with a local end connected to said subscriber server; and

an analog subscriber telephone having a safety life line connectable by a switch through the conductor wire pair to said second external network interface facilities for providing a backup communication link through said dedicated line cards in said second external network interface facilities when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment, said switch bypassing said multiplexer components in said first external network interface and said subscriber server.

9. A multiple access subscriber link providing telecommunications between customer premise equipment and external networks, comprising:

first external network interface facilities having non-dedicated time shared multiplexer components for processing broadband transmission of voice, data and/or signaling;

second external network interface facilities having multiple dedicated line cards for handling narrowband plain old telephone (POT) transmissions;

a subscriber server having interconnections with multiple customer premise devices;

a conductor wire pair with a remote end connected to said first and said second external network interface facilities, and with a local end connected to said subscriber server; and

an analog subscriber telephone having a safety life line connectable through the conductor wire pair to said second external network interface facilities for providing a backup communication link through said dedicated line cards in said second external network interface facilities when there is a failure of a system or component associated with any of said first external network facilities, said subscriber server, and the customer premise equipment, wherein said safety life line connection is provided using a first portion of a frequency spectrum of the multiple access subscriber link.