Distributed processing for optimal QOS in a broadband access system

• US 20020056132A1
• Filed: 01/26/2001
• Published: 05/09/2002
• Est. Priority Date: 01/26/2000
• Status: Active Grant

• Current Assignee: VYYO, Ltd.
• Original Assignee: VYYO, Ltd.
• Inventors: Wilson, Eric K.
• Granted Patent: US 7,149,188 B2
• Time in Patent Office: Days
• US Class Current: 725/118
• CPC Class Codes: H04L 1/0001 Systems modifying transmission characteristics according to link quality, e.g. power backoff adaptive data allocation for multicarrier modulation H04L5/0044; controlling transmission power for radio systems H04W52/04
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0025 Transmission of mode-switching indication
• CPC Class Codes: H04L 1/0027 Scheduling of signalling, e.g. occurrence thereof
• CPC Class Codes: Y02D 30/50 in wire-line communication networks, e.g. low power modes or reduced link rate

Abstract

A method for distributing the QOS processing in a broadband access system to the system modems and the head-end equipment. Requests for a change in the operating parameters are transmitted on an exception basis, thereby greatly reducing the amount of system over-head required. In the upstream, the Cable Modem Termination System (CMTS) or Wireless Modem Termination System (WMTS or Wireless Hub) determines a signal-to-noise ratio (SNR) or Bit Error Rate (BER) (or similar measurable parameter) quality data for each received packet. If a measured parameter is outside of the predetermined limits, then the WMTS reports to the NMS (Network Management Operating System) the modem ID and the measured data of the particular packet. The NMS may then modify the operating parameters. In the downstream, each modem determines an SNR or BER (or some other measurable parameter) measurement for the incoming packets. These values may be compared to some boundary conditions. If the system is performing outside the boundary conditions, the modem sends an exception message to the NMS which reassigns the modem to a different downstream channel or modifies the channel parameters.

Claims

1. A method for distributed upstream quality of service (QOS) processing in a broadband access system, the method comprising:

measuring a quality of received packets sent by a modem in an upstream channel at an upstream modem termination system;

determining whether the measured quality is within a predetermined range;

reporting an out-of-range quality for the received packets to a network management server; and

modifying operating parameters for the upstream channel in accordance with the measured quality, if an out-of-range quality is reported.

2. The method of claim 1, wherein measuring a quality of received packets comprises measuring a signal-to-noise ratio (SNR).

3. The method of claim 1, wherein measuring a quality of received packets comprises measuring a bit error rate (BER).

4. The method of claim 1, wherein measuring a quality of received packets comprises measuring a Forward Error Correction (FEC) quality measure.

5. The method of claim 1, wherein if the quality measure is below a predetermined lower limit for some averaged or weighted averaged value for a series of packets, then the modem ID and the measured quality data of a particular packet or average is reported to the network management server.

6. The method of claim 5, wherein the network management server reassigns the modem to a different downstream channel in the same or overlapping. sector, which has a different operating frequency.

7. The method of claim 5, wherein the network management server reassigns the modem to a lower order modulation type.

8. The method of claim 5, wherein the network management server reassigns the modem to a lower symbol rate.

9. The method of claim 5, wherein the network management server reassigns the modem to a more robust Forward Error Correction scheme.

10. The method of claim 5, wherein the network management server reassigns the modem to a combination of a different frequency, a lower order modulation type, a lower symbol rate, and a more robust Forward Error Correction scheme.

11. The method of claim 1, wherein if the quality measure is above a predetermined upper limit for some averaged or weighted averaged value for a series of packets, then the modem ID and the measured quality data of a particular packet or average is reported to the network management server.

12. The method of claim 11, wherein the network management server reassigns the modem to a channel with a higher order modulation.

13. The method of claim 11, wherein the network management server reassigns the modem to a different type of modulation.

14. The method of claim 11, wherein the network management server reassigns the modem to a faster symbol rate.

15. The method of claim 11, wherein the network management server reassigns the modem to a lower Forward Error Correction scheme.

16. The method of claim 11, wherein the network management server reassigns the modem to a channel which has similar parameters but less traffic.

18. The method of claim 17, wherein if the measured quality is below a lower limit, the network management server reassign the modem to a different downstream channel.

19. The method of claim 17, wherein if the measured quality exceeds an upper limit, then the modem sends an exception signal offering to move to a less utilized channel.

20. The method of claim 17, wherein if the measured quality exceeds an upper limit, then the modem sends an exception signal offering to move to a channel with a higher net data rate.

21. The method of claim 17, wherein if the measured quality is below a lower boundary condition, the exception is sent with a high priority, and if the measured quality is above a high boundary condition, the exception is sent with a lower priority.

17. A method for distributed downstream quality of service (QOS) processing in a broadband access system, the method comprising:

measuring a quality of received packets in a downstream channel at a modem;

comparing the measured quality with predetermined boundary conditions;

determining whether the measured quality is within the predetermined boundary conditions;

sending an exception to a network management server, if the measured quality is outside the boundary conditions; and

modifying operating parameters for the downstream channel in accordance with the measured quality.

22. A method for distributed processing for optimal quality of service (QOS) in a broadband access system, the method comprising:

a method for distributed upstream quality of service (QOS) processing, the method comprising;

measuring a quality of received packets sent by a modem in an upstream channel at an upstream modem termination system;

determining whether the measured quality is within a predetermined range;

reporting an out-of-range quality for the received packets to a network management server; and

modifying operating parameters for the upstream channel in accordance with the measured quality, if an out-of-range quality is reported; and

a method for distributed downstream quality of service (QOS) processing, the method comprising;

measuring a quality of received packets in a downstream channel at a modem;

comparing the measured quality with predetermined boundary conditions;

determining whether the measured quality is within the predetermined boundary conditions;

sending an exception to a network management server, if the measured quality is outside the boundary conditions; and

modifying operating parameters for the downstream channel in accordance with the measured quality.