Signal protection
A signal protector utilizes a variable latency station to provide error correction.
1. A data protection method comprising the steps of:
providing data path A and data path B;
each of the data paths extending between first and second stations;
the first station providing data to path A;
the second station receiving data initially from data path A; and,
providing an uninterrupted second station output following a data fault via
utilizing a buffer of the second station to maintain an unfaulted second station output after the data fault is detected,
the first station providing data to data path B, the data including resend data from a first station buffer, the resend data including data that replaces the faulted data, and
the data from data path B bypassing at least a portion of the second station buffer to merge the resent data with the data remaining in the second station buffer.
2. The data protection method of claim 1 further comprising the steps of:
sizing the buffer of the second station such that the time required for a bit to traverse the second station buffer equals or exceeds t;
where t=t 1 +t 2 ;
where t 1 equals the time required for one bit of data to traverse path A; and,
where t 2 equals the time required for one bit of data to traverse path B.
3. The data protection method of claim 2 further comprising the step of sizing the buffer of the first station such that the time required for a bit to traverse the first station buffer equals or exceeds t.
4. The data protection method of claim 1 further comprising the steps of:
sizing the buffer of the second station such that the time required for a bit to traverse the second station buffer equals or exceeds t+r 1 +r 2 +r 3 ;
where t=t 1 +t 2 ;
where t 1 equals the time required for one bit of data to traverse path A;
where t 2 equals the time required for one bit of data to traverse path B;
where r 1 equals the time required by the second station to detect the fault;
where r 2 equals the time required by the first station to respond to a received request to resend data including data replacing the faulty data; and,
where r 3 equals the time required by the second station to merge resent data with data remaining in the second station buffer.
5. The data protection method of claim 4 further comprising the step of sizing the buffer of the first station such that the time required for one bit of data to traverse the first station buffer equals or exceeds t+r 1 +r 2 .
6. The data protection method of claim 5 further comprising the step of the second station sending a request to resend data replacing the faulty data and the first station receiving the request during a time period substantially equal to t 1 .
7. The data protection method of claim 6 further comprising the step of the first station beginning to send resend data and the second station beginning to receive resend data during a time period substantially equal to t 2 .
8. The data protection method of claim 1 further comprising the step of rebuilding the second station buffer wherein rebuild operations include
operating path B at a data rate higher than a nominal data rate for path B,
utilizing some of the path B data to maintain a second station buffer output at its nominal data rate,
utilizing some of the path B data to rebuild the second station buffer, and
returning the path B data rate to its nominal data rate after the second station buffer has been rebuilt.
9. The data protection method of claim 8 further comprising the step of the second station relying on path B to maintain the second station buffer.
10. The data protection method of claim 9 further comprising the step of relying on path A to rebuild and maintain the second station buffer following a transmission fault detected while path B is active.
11. The data protection method of claim 1 wherein data transported on path A is not transported on path B unless a fault is detected in a data earlier transported on path A.
12. The data protection method of claim 1 wherein bandwidth consumption is limited to a single data path unless a data fault is detected.
13. The data protection method of claim 1 wherein to the extent data is simultaneously transported on data path A and data path B, the data loaded onto the paths by the first station is not replica data.
14. The data protection method of claim 1 wherein the second station has but a single data buffer.