Broadband video switch that performs program merging and method therefor

• US 6,243,388 B1
• Filed: 12/30/1997
• Issued: 06/05/2001
• Est. Priority Date: 11/30/1994
• Status: Expired due to Fees

• Current Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Original Assignee: Verizon Laboratories Incorporated (Verizon Communications Inc.)
• Inventors: Liu, Stephen S., Mussman, Harry Edward, Helmes, Thomas R.
• Primary Examiner(s): Hsu, Alpus H.
• Assistant Examiner(s): HO, DUC CHI
• Application Number:
  US09/000,907
• Time in Patent Office: 1,253 Days
• Field of Search: 370/410, 370/426, 370/485, 370/486, 370/496, 370/432, 370/390, 709/219, 348/7, 348/16, 455/416, 455/3.1, 455/4.2, 455/5.1, 379/202, 379/247, 725/78, 725/80, 725/82
• US Class Current: 370/420
• CPC Class Codes: H04J 3/0685 Clock or time synchronisation in a node; Intranode synchronisation
• CPC Class Codes: H04L 7/0337 Selecting between two or more discretely delayed clocks or selecting between two or more discretely delayed received code signals

Abstract

A network (10) includes a broadband customer service module (B-CSM) (20). The B-CSM (20) includes a plurality of feeder interface cards (FICs) (36) and optical line cards (OLCs) (38) which are coupled together through a midplane assembly (34) so that each FIC (36) couples to all OLCs (38) and each OLC (38) couples to all FICs (36) through junctor groups (68). Within the B-CSM (20) circuit switching is performed electrically at an STS-1 rate. A reference clock which oscillates at a frequency slower than the data rate is routed with payload data so that it receives delays similar to those imposed on the payload data due to processing. At second stage switching fabrics (50) where data need to be extracted from signals flowing within the B-CSM (20), a clock regeneration circuit (32) generates a master clock signal oscillating at twice the data rate and phase synchronized to a delayed reference clock. A geometric compensation scheme corrects for timing skew which occurs when clocks and data are distributed to points or small areas from widely dispersed locations, and when clocks and data are distributed from points or small areas to widely dispersed locations. A variation of the Q.931 signaling protocol is implemented to enable the B-CSM (20) to respond to a request from a second subscriber interface unit (SIU) (100) to view a video program currently being delivered to a first SIU (100). The second SIU (100) need not have access to the identity of the video program before sending the switching request.

Claims

1. A broadband video switch operating method for managing communication signal traffic, said method comprising the steps of:

(a) delivering a communication signal to a first customer unit located at a customer site, said communication signal being identified by an identification code;

(b) receiving a message from a second customer unit located at said customer site, said message being a merge request identifying said first customer unit and lacking said identification code for said communication signal; and

(c) delivering said communication signal to said second customer unit in response to said merge request.

2. A method according to claim 1, wherein said merge request includes an information element configured as a switching instruction, said switching instruction including a unique unit subaddress associated with said first customer unit for identifying said first customer unit.

3. A method according to claim 1, wherein:

said first customer unit is identified by a first subscriber address;

said second customer unit is identified by a second subscriber address; and

said message includes a plurality of information elements that convey at least said first and second subscriber addresses.

4. A method according to claim 3, wherein said first subscriber address includes a subscriber number in conjunction with a first unique unit subaddress and said second subscriber address includes said subscriber number in conjunction with a second unique unit subaddress.

5. A method according to claim 1, wherein said communication signal is delivered substantially concurrently to said first and second customer units following said step (c).

6. A broadband video switch operating method for managing communication signal traffic, said method comprising the steps of:

(a) delivering a communication signal to a first customer unit located at a customer site, said communication signal being identified by an identification code;

(b) receiving a message from a second customer unit located at said customer site, said message being a merge request identifying said first customer unit and lacking said identification code for said communication signal; and

(c) delivering said communication signal to said second customer unit in response to said merge request;

(d) terminating delivery of said communication signal to one of said first and second customer units; and

(e) maintaining delivery of said communication signal to the other of said first and second customer units following said terminating step.

7. A broadband video switch operating method for managing communication signal traffic between a remote switching module and at least one customer site having first and second customer units, said method comprising the steps of:

(a) receiving a plurality of communication signals at said remote switching module;

(b) obtaining a message from said second customer unit, said message being a merge request identifying said first customer unit; and

(c) delivering, in response to said merge request, one of said communication signals to said second customer unit when said one communication signal is currently being delivered to said first customer unit wherein said one communication signal is identified by an identification code and said merge request lacks said identification code for said one communication signal.

8. A method according to claim 7, wherein said merge request includes an information element configured as a switching instruction, said switching instruction including a unique unit subaddress associated with said first customer unit for identifying said first customer unit.

9. A method according to claim 7, wherein:

said first customer unit is identified by a first subscriber address;

said second customer unit is identified by a second subscriber address; and

said message includes a plurality of information elements that convey at least said first and second subscriber addresses.

10. A method according to claim 9, wherein said first subscriber address includes a subscriber number in conjunction with a first unique unit subaddress and said second subscriber address includes said subscriber number in conjunction with a second unique unit subaddress.

11. A method according to claim 7, wherein said one communication signal is delivered substantially concurrently to said first and second customer units following said step (c).

12. A method according to claim 7, further comprising the steps of:

terminating delivery of said one communication signal to one of said first and second customer units; and

maintaining delivery of said one communication signal to the other one of said first and second customer units following said terminating step.

13. A broadband video switch that manages communication signal traffic between a remote switching module and at least one customer site having first and second customer units, said switch comprising:

means for receiving a plurality of communication signals;

means for obtaining a message from said second customer unit, wherein said message is a merge request configured to identify said first customer unit and said merge request is configured to lack an identification code for one of said communication signals; and

a plurality of switching modules configured to deliver, in response to said merge request, said one of said communication signals to said second customer unit when said one communication signal is currently being delivered to said first customer unit.

14. A switch according to claim 13, wherein:

said first customer unit is identified by a first subscriber address;

said second customer unit is identified by a second subscriber address; and

said message is configured to include a plurality of information elements that convey at least said first and second subscriber addresses.

15. A switch according to claim 13, wherein said switching modules are configured to maintain delivery of said one communication signal to said first customer unit while delivering said one communication signal to said second customer unit.

16. A switch according to claim 13, wherein said switching modules are configured to maintain delivery of said one communication signal to one of said first and second customer units after terminating delivery of said one communication signal to the other one of said first and second customer units.