What is the role of the glass cladding in a fiber optic cable?

The role of glass cladding in a fiber optic cable is pivotal in ensuring effective signal transmission through optical fibers. The cladding surrounds the glass core, which is the central part where light is transmitted. One of its critical functions is to reduce light loss by reflecting light back into the core.

When light travels through the core, it reaches the boundary between the core and the cladding. Because the cladding has a lower refractive index than the core, the light is kept confined within the core due to a principle known as total internal reflection. This reflection minimizes the loss of light and ensures that the signal can travel long distances with minimal degradation, making it an essential component in maintaining the quality and efficiency of data transmission in fiber optic systems.

In contrast, while the glass cladding does provide some protection and structural aspects, these are not its primary functions compared to the importance of controlling light propagation. Thus, the central role of cladding lies in its ability to reflect and guide light effectively, which is why this answer is the most appropriate.