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When disaster strikes – A real fiber monitoring story from F6 Networks


EXFO designed the Fiber Guardian stand-alone OTDR remote test unit to help network operators deal more efficiently with any gradual or sudden deterioration of their fiber’s condition—and without the heavy maintenance required by other commercial solutions.


But don’t just take our word for it: hear it firsthand from open-access provider F6 Networks, who has offered to share its experiences about the impact the FG unit had on reducing fiber fault location from hours to minutes, in turn keeping customers informed and reducing OPEX with less truck rolls.

Here’s the lowdown of a recent conversation we had with a representative from F6 Networks about their experience with the Fiber Guardian unit:

EXFO: What initially triggered your interest in a fixed OTDR for 24/7 surveillance and led you to invest in the Fiber Guardian unit?

F6 Networks: We began as a strictly dark-fiber network operator. Had we not invested in the unit, we would have had to rely on our customers to report outages or problems. That would have meant being strictly reactive in responding to network issues rather than proactively monitoring critical dark fiber routes. We’ve been using the unit to monitor our network since the outset, and are using the same unit today to monitor both metro rings and long-haul dark fiber.

EXFO: What role did Fiber Guardian play in helping you manage a major cable outage during a recent storm/hurricane?

F6 Networks: Every minute counts during service-impacting events. When post‑tropical storm Arthur battered much of the Maritimes this past July, we suffered a fiber cut in a remote location. The fiber monitoring system immediately notified us of the damage, enabling us to pinpoint the break in our records within minutes. We were able to advise all affected customers before they had the chance to report the problem, and had a restoration crew en route to the exact location within ten minutes. Our total time from outage to full restoration was less than four hours. Had it not been for the ability to immediately pinpoint the location, we would have had to rely on a technician to travel to a point‑of‑presence (PoP) site, perform a trace, use records to estimate the location, and then direct the restoration team to the area to search for the break.

EXFO: Was traffic rerouted during this time, and do you consider time to repair (TTR) important here despite possible diversity?

F6 Networks: TTR is critical on any cable break or outage. Our customers have redundant links; however, we treat such events as “hard-down” situations for which primary service must be restored as quickly and safely as possible.

EXFO: What other benefits have you experienced in the past one and a half years that you have been using the unit?

F6 Networks: In addition to using the Fiber Guardian to monitor applications, we employ it as a preliminary test unit when building out new routes or laterals to customers. We have a designated “Test Port” on the unit that we use to check splices as they are being completed (and while the splicer’s closure is still in his truck). This enables us to verify that the splice losses meet our specifications before the closure is placed back into the manhole/pole, thus preventing rework resulting in substantial cost increases emanating from traffic control, maintenance and windows, etc. Once splicing is complete, we perform acceptance testing (bidirectional OTDR traces and loss testing) using our FTB field units.

About F6 Networks

F6 Networks owns and operates a high‑capacity fiber network that currently connects New Brunswick to the Northeast US, and which will soon also connect Nova Scotia and Quebec. The company also delivers Connect Solutions enabling customers to build more robust, secure and cost-effective networks.