... module support 155M/622M/2.5G SDH/SONET and PDH/DSn test functionalities and offer comprehensive test solutions ... and troubleshootingSDH optical modules and components testing Key FeaturesPDH:1.5Mb/s,2Mb/s,34Mb/s,45Mb/s ,140Mb ... /sPDH test: 1.5Mb/s, 2Mb/s, 34Mb/s, 45Mb/s ... optical interfaces SDH test: 155Mb/s electrical interface (STM-1)High-order (HO) and low-order (LO) mapping, ...