Dual line monitoring of 1‘protection with auto-switch

• US 20030189897A1
• Filed: 04/09/2002
• Published: 10/09/2003
• Est. Priority Date: 04/09/2002
• Status: Abandoned Application

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Einstein, David E., Sha, Yung-Ching
• Application Number:
  US10/119,225
• Publication Number:
  US 20030189897A1
• Time in Patent Office: Days
• US Class Current: 370/220
• CPC Class Codes: H04J 14/029 Dedicated protection at the optical multiplex section (1+1)
• CPC Class Codes: H04J 14/0297 Optical equipment protection
• CPC Class Codes: H04J 3/14 Monitoring arrangements for SDH/SONET rings H04J3/085
• 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 1/22 using redundant apparatus to increase reliability

Abstract

A method and apparatus implementing a “1+1” protection scheme using two interface cards (transmitter and receiver) having a mathematically provable uptime rate.

Claims

1. Apparatus, comprising:

a switch for providing received data traffic from one of a service line and a protection line to an interface device; and

a controller, for causing said switch to alternately select said service and protection lines according to a switch rate selected to provide a minimum system uptime rate.

2. The apparatus of claim 1, further comprising:

at least one optical power monitoring device for determining an optical power level of at least one of said service line and said protection line;

said controller, in response to a signal from said at least one optical power monitoring device, causing said switch to avoid selecting a line exhibiting an inappropriate optical power level.

3. The apparatus of claim 1, wherein:

said controller, in response to a signal said interface card, causing said switch to deselect a line exhibiting an inappropriate performance level.

4. The apparatus of claim 3, wherein said inappropriate performance level comprises a bit error rate (BER) above a threshold level.

5. The apparatus of claim 1, wherein said switch rate is determined according to the following equation:

6. The apparatus of claim 1, wherein said system uptime rate (SUR) is determined according to the following equation:

SUR=1−

[(F*R*F)/(2*S)+(F*R*F*R)/Y+S*T]/Y

wherein F is the average number of signal conditions per line in a year;

R is the average repair time of a line signal condition once it is detected;

S is the number of auto-switch operations occurring in a year;

T is the average switch time of an auto-switch operation;

U is the system average un-available time;

Y is the total time in a year.

F;

The average number of signal conditions per line in a year.

R;

The average repair time of a line signal condition once it is detected.

S;

The number of auto-switch operations occurring in a year.

T;

The average switch time of an auto-switch operation.

7. A system, comprising:

a switch, for routing received data traffic from one of a service line and a protection line to an interface device according to a determined switching rate, said switching rate determined in accordance with a desired system uptime rate.

8. The system of claim 7, wherein said switch rate is determined according to the following equation:

9. The system of claim 7, further comprising:

a first optical power measurement apparatus for measuring the optical power of said service line, and a second optical power measurement apparatus for measuring the optical power of said protection line, said first and second optical power measurement apparatus providing output signals indicative of

10. The system of claim 7, further comprising:

an optical splitter, for splitting optical data traffic provided by a second interface device into a first data stream for transmission to said switch via said service line a second data stream for transmission to said switch via said protection line.

11. In a system comprising a switch for providing received data traffic from one of a service line and a protection line to a single interface device, a method for providing a desired system uptime rate, comprising:

causing said switch to alternately select said service and protection lines according to a switch rate selected to provide said desired system uptime rate.

12. The method of claim 11, further comprising:

determining an optical power level of at least one of said service line and said protection line; and

causing said switch to avoid selecting a line exhibiting an inappropriate optical power level.

13. The method of claim 12, wherein said inappropriate optical power level is determined by an optical power monitoring device associated with a said inactive line.

14. The method of claim 11, further comprising:

determining a quality of service (QoS) performance level of a selected one of said service line and protection line; and

causing said switch to deselect a line exhibiting an inappropriate performance level.

15. The method apparatus of claim 14, wherein said inappropriate performance level comprises a bit error rate (BER) above a threshold level.

16. The method of claim 11, further comprising:

causing said switch to alternately select said service and protection lines according to a switch rate (S) determined according to the following equation;

$S=\frac{1}{2*T}*[\left(Y-A*Y-\frac{F*R*F*R}{Y}\right)<br><br><br><br>\text{\hspace{1em}<br><br>}\pm <br><br>\sqrt{\left(A*Y-Y+F*R*F*R/Y\right)*\left(A*Y-Y+F*R*F*R/Y\right)-2*T*F*R*F}<br><br>\text{\hspace{1em}<br><br>};<br><br>$

wherein F is the average number of signal conditions per line in a year;

R is the average repair time of a line signal condition once it is detected;

S is the number of auto-switch operations occurring in a year;

T is the average switch time of an auto-switch operation;

U is the system average un-available time;

Y is the total time in a year; and

A is the system target uptime rate.

17. In a system comprising a switch for providing received data traffic from one of a service line and a protection line to a single interface device, a method for providing a desired system uptime rate, comprising:

causing said switch to alternately select said service and protection lines according to a switch rate (S) adapted to provide said desired system uptime rate according to the following equation;

SUR=1−

[(F*R*F)/(2*S)+(F*R*F*R)/Y+S*T]/Y

wherein F is the average number of signal conditions per line in a year;

R is the average repair time of a line signal condition once it is detected;

S is the number of auto-switch operations occurring in a year;

T is the average switch time of an auto-switch operation;

U is the system average un-available time;

Y is the total time in a year.