Time-based link fault localization

A first network element to determine an estimated physical location of a fault in a physical communications link that is to be utilized by the first network element and a second network element, the first network element comprising:

• a set of one or more physical network interfaces configured to:
• transmit, to the second network element, a first plurality of bits over the physical communications link,
• receive, from the second network element, a second plurality of bits over the physical communications link, and
• receive, from the second network element, a first link failure indication that is to include a first time value received by the second network element from the first network element over the physical communications link;
• a link fault detection module configured to:
• detect that the fault of the physical communications link has occurred, and
• generate, responsive to said detection, a second link failure indication that is to include a second time value;
• and
• a link fault localization module configured to:
• determine a time distance between the first time value and the second time value, and
• calculate the estimated physical location of the fault based upon the time distance.

An apparatus to determine an estimated physical location of a fault in a physical communications link to be utilized by a first network element and a second network element, the apparatus comprising:

• a set of one or more physical network interfaces configured to:
• receive, from the first network element, a first link failure indication that is to include a first time value that is to be received by the first network element from the second network element over the physical communications link, and
• receive, from the second network element, a second link failure indication that is to include a second time value, wherein the second time value is to be received by the second network element from the first network element over the physical communications link;
• and
• a link fault localization module configured to:
• determine a time distance between the first time value and the second time value, and
• calculate the estimated physical location of the fault based upon the time distance.

A method performed by a server end station for determining an estimated physical location of a fault in an optical link utilized by a first optical switch and a second optical switch, the method comprising:

• receiving a first link failure indication from the first optical switch, wherein the first link failure indication comprises a first time value that was received by the first optical switch from the second optical switch over the optical link;
• receiving a second link failure indication from the second optical switch, wherein the second link failure indication comprises a second time value that was received by the second optical switch from the first optical switch over the optical link;
• determining a time distance between the first time value and the second time value;
• and
• calculating the estimated physical location of the fault based upon the time distance.

A server end station to determine an estimated physical location of a fault in an optical link utilized by a first optical switch and a second optical switch, the server end station comprising:

• a set of one or more physical ports configured to:
• receive, from the first optical switch, a first link failure indication that is to include a first time value that was received by the optical switch from the second optical switch over the optical link, and
• receive, from the second optical switch, a second link failure indication that is to include a second time value that was received by the second optical switch from the first optical switch over the optical link;
• and
• a link fault localization module configured to:
• determine a time distance between the first time value and the second time value, and
• calculate the estimated physical location of the fault based upon the time distance.