... can build (connected with RSM-155C) various complex networks of STM-1 multi-ring, and multi-branch, etc. Provides timing synchronous ... , implements switching of multiple timing sources like 2Mb/s, 2MHz, STM-1, etc., and output of 2Mb/s, 2MH reference clock ... (EOW) interface, with group call and dial functions6-optical-port, STM-1 MADM or TM multiplexer;Support up to 231 E1 ...