Distributed Fiber Optic Sensing (DFOS) systems provide critical asset monitoring by utilizing standard fiber optic cables as sensors. This is the power of fiber optic sensing, a technology that transforms ordinary optical fibers into the digital world's sensory network. In 2023, researchers turned submarine cables into earthquake warning systems and gave electric vehicles “optical nerves” to prevent battery failures. From energy. Distributed Temperature Sensing (DTS), Distributed Temperature and Strain Sensing (DTSS) and Distributed Acoustic Sensing (DAS) are all various types of fiber optic sensing technologies which use the physical properties of light as it travels along a fiber to detect changes in temperature, strain. This paper introduces the basic principles of several commonly used optical fiber sensors and the progress of optical fiber sensors in the monitoring of physical, mechanical, and chemical parameters and demonstrates the applications of optical fiber sensors in infrastructure. Introduction. Real-time monitoring and insight for critical infrastructure—delivering continuous, long-range visibility across pipelines, transportation networks, and security environments.