Remote test methods of optical cable short insert losses

During fiber optic communication lines restoration often appear optical cable short insert joint quality control needs. It is problem to measure of short cable insert fiber splice losses on long-haul optical communication lines. This problem is caused by limits of dynamic range and resolution of optical time domain reflectometer (OTDR). We present overview of ways of short cable insert optical power losses control on long- haul optical communication lines. Theoretical and experimental proof some of this methods is considered. Numerical results are represented. A good agreement of theoretically predicted and experimental values is demonstrated.