SDH stands for “Synchronous Digital Hierarchy” and represents a standardized method of data transmission in telecommunications systems. SDH allows many individual data streams to be combined into larger data streams, enabling more efficient and faster communication.
This technology works in a synchronized network based on an uniform clock. Compared to the previous PDH technology, SDH offers faster transmission rates and is more cost-efficient. It is used in the transmission of various communication signals such as ATM cells and Ethernet aggregations. SDH technology uses different transmission rates to transport data streams with different capacities. SDH networks consist of a series of nodes connected by different transmission media such as fiber optics and copper cables.
They offer flexibility, rapid response to failures and mechanisms for error detection and fault isolation. Compared to older multiplex standards, SDH offers improved compatibility between different manufacturers, simpler interoperability, clear interfaces and high transmission speeds.