Power meter and light source testing are frequently referred to as the one-jumper method. The jumper method is the most accurate way to measure attenuation or end-to-end signal loss over a fiber optic cable. We've listed the TIA/EIA –. Power meter and light source testing are frequently referred to as the one-jumper method. The jumper method is the most accurate way to measure attenuation or end-to-end signal loss over a fiber optic cable. We've listed the TIA/EIA – 568 insertion loss limit for connector pairs and splices. Specific installation or protocols will require stricter. Using a visible light sourcetests the continuity of fiber optic cabling. Because fiber optic transmissions work in the infrared portion of the electromagnetic spectrum, they are invisible to the naked eye. We can use visible light sources for troubleshooting and testing fiber optics networks. These types are visual fault finders or visible fault lo. Using optical time domain reflectometer testing, you'll measure the length of the fiber optic cable, attenuation, and any events occurring on that fiber segment. Events are splices, stress points, or breaks that cause unacceptable amounts of attenuation on the length of the fiber. OTDRtesting does this by emitting pulses of light down the fiber opt.