1. Outline: Comparison between PDH and SDH. STM-N frame structure. Multiplexing of of 140Mb/s, 34Mb/s and 2Mb/s signals into STM-N frame. Common NE of SDH network. SDH network structure and network protection mechanism. Management, monitoring and alarms.

2. Comparison between PDH and SDH SDHPDHPoint of comparison universal standard No universal standard Electrical & Optical Interface simplecomplexmultiplexing method High administration Poor administration Operation, administration & Maintenance compatible with other signals (ATM, FDDI &DQDB) Incompatible with other signals (ATM, FDDI &DQDB) Compatibility High B.WSave B.WBandwidth High coastLow coastCoast

3. Electrical interface PDH

4. SDH Electrical interface

5. Multiplexing Method