Optical network system and method for supporting upstream signals propagated according to a cable modem protocol

• US 20060269285A1
• Filed: 03/27/2006
• Published: 11/30/2006
• Est. Priority Date: 01/08/2002
• Status: Active Grant

• Current Assignee: ARRIS Solutions, Inc. (CommScope Holding Company, Inc.)
• Original Assignee: Wave7 Optics, Inc. (Enablence Technologies Incorporated)
• Inventors: Thomas, Stephen, Quinn, Patrick, Farmer, James
• Granted Patent: US 7,583,897 B2
• Time in Patent Office: Days
• US Class Current: 398/72
• CPC Class Codes: H04J 3/0664 unidirectional timestamps
• CPC Class Codes: H04J 3/0682 by delay compensation, e.g. by compensation of propagation delay or variations thereof, by ranging
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/64707 for transferring content from a first network to a second network, e.g. between IP and wireless
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications
• CPC Class Codes: H04N 7/22 Adaptations for optical transmission

Abstract

A modification to a cable modem termination system (CMTS) can include instructing the CMTS to ignore or skip steps of its timing algorithm so that upstream cable modem signals are controlled only by the upstream protocol of the optical network system. According to another exemplary aspect, a time stamp can be added to the upstream cable modem signals so that the CTMS timing scheme can be used. This time stamp can be used in the data service hub to adjust for the delays that occur while the upstream cable modem signals are sent across the optical network. Another adjustment of the CMTS timing scheme can include using less than a total number of miniature time slots for upstream cable modem transmissions. According to another exemplary aspect, a cable modem termination system can be positioned within a laser transceiver node or a subscriber optical interface.

Claims

1. A method for supporting upstream signals propagated according to a cable modem protocol sent over an optical network comprising:

selecting a first magnitude of a downstream time synchronization interval for the cable modem protocol;

dividing the downstream time synchronization interval into a plurality of equally sized mini-slots;

transmitting upstream signals over the optical network according to the cable modem protocol;

storing the upstream signals temporarily in the optical network; and

processing the upstream signals with a cable modem termination system.

2. The method of claim 1, wherein the transmitting of upstream signals further comprises transmitting upstream signals by using alternate mini-slots.

3. The method of claim 1, wherein the transmitting of upstream signals further comprises transmitting upstream signals by using mini-slots in a series.

4. The method of claim 1, wherein the transmitting of upstream signals further comprises sending upstream signals by using mini-slots in a series and not using one or more mini-slots after the series.

5. The method of claim 1, wherein the cable modem protocol comprises a Data Over Cable Service Interface Specification.

6. The method of claim 1, wherein storing the upstream signals temporarily in the optical network further comprises storing the upstream signals in a routing device within the optical network.

7. The method of claim 1, wherein transmitting upstream signals over the optical network according to the cable modem protocol further comprises transmitting by using less than a total number of the mini-slots during a given time synchronization interval.

8. A method for supporting upstream signals propagated according to a cable modem protocol sent over an optical network comprising:

receiving the upstream signals;

monitoring a downstream time synchronization;

adding a time stamp to the upstream signals based on the downstream time synchronization;

converting the upstream signals into the optical domain; and

sending the upstream optical signals over the optical network to the cable modem termination system.

9. The method of claim 8, wherein monitoring a downstream time synchronization comprises monitoring a media access control management message sent by a cable modem termination system.

10. The method of claim 8, wherein monitoring a downstream time synchronization comprises monitoring a time message produced by a circuit that is independent of a cable modem termination system.

11. The method of claim 8, further comprising holding the upstream signals for a predetermined time period based on the time stamp before sending the upstream signals to the cable modem termination system.

12. The method of claim 8, further comprising converting the upstream signals from an analog format to a digital format.

13. The method of claim 8, further comprising reducing a size of the upstream signals.

14. The method of claim 8, wherein the cable modem protocol comprises a Data Over Cable Service Interface Specification.

15. A method for supporting signals propagated according to a cable modem protocol sent over an optical network comprising:

providing a data service hub at one end of the optical network that originates video and data services for subscribers;

positioning a cable modem termination system within one of a laser transceiver node and a subscriber optical interface;

processing upstream signals propagated according to the cable modem protocol with the cable modem termination system; and

forwarding the processed upstream signals from the cable modem termination system over the optical network to the data service hub.

16. The method of claim 15, wherein the step of positioning a cable modem termination system outside of the data service hub further comprises placing the cable modem termination system in a laser transceiver node that comprises a routing device.

17. The method of claim 15, wherein the step of positioning a cable modem termination system outside of the data service hub further comprises placing the cable modem termination system in a subscriber optical interface that converts upstream electrical signals into optical signals.

18. A method for supporting upstream signals propagated according to a cable modem protocol sent over an optical network comprising:

overriding a time synchronization routine of the cable modem protocol;

receiving upstream cable modem signals based on an upstream protocol of the optical network that is different from the cable modem protocol; and

processing the upstream cable modem signals with a cable mode termination system.

19. The method of claim 18, wherein overriding a time synchronization routine of the cable modem protocol further comprises overriding a time synchronization routine of cable modem protocol comprising a Data-Over-Cable Service Interface Specification (DOCSIS).

20. The method of claim 18, wherein overriding a time synchronization routine of the cable modem protocol further comprises causing a cable modem protocol to ignore any unique response time intervals assigned to one or more cable modem devices.

21. The method of claim 18, further comprising managing upstream data signals originating from devices other than cable modems with the upstream protocol of the optical network.