Approved 31-206 ZCTA of Transmission(SDH), Transmission (SDH) after-sales engineer Exam – Success Pathway Course

[31-206 ZCTA of Transmission(SDH), Transmission (SDH) after-sales engineer Exam] In This Course of ,The SDH exam validates expertise in legacy synchronous digital hierarchy networks still widely used in carrier operations. Topics include STM-1/4/16/64 hierarchies, multiplexing, protection switching, synchronization, fault management, and migration to next-gen systems. Engineers must ensure service continuity, perform preventive maintenance, and resolve transmission errors.