Bidirectional testing involves measuring the fiber from both ends. Typically, you perform a test from one end, then move the equipment to the other end and repeat the test. The FTB Lite 975 provides bidirectional Tier-1 OLTS measurements (ORL, IL, length, and polarity) and also offers OTDR capabilities (upcoming). FTB Lite 975 makes it easy to test and certify all fiber-optic cables and connector types, from simplex and duplex to multi-fiber (base 8/12/16 up to 24). On the home screen, tap the Next ID panel. Fiber optic testing of a newly installed system not only verifies that the system meets its design requirements, but also creates a performance baseline for all future testing and troubleshooting of t at system.