Synchronous Transport Module (STM)

A Synchronous Transport Module (STM) is a standardized unit of data transmission used in telecommunications, part of the Synchronous Digital Hierarchy (SDH) network. It efficiently carries multiple types of digital signals—like phone calls, internet data, or video—over fiber optic or microwave links. Think of it as a container that organizes and synchronizes various data streams so they move together seamlessly at high speeds. The most common, STM-1, transmits data at 155 Mbps, with larger modules like STM-4, STM-16, and STM-64 handling even more data by stacking multiple STM-1 units.