Indoor fiber optic cables are built to last, with an average lifespan of 20 to 30 years. However, various factors such as environmental conditions, usage, and cable quality play significant roles in determining how long these cables will serve your needs. But ask any veteran network engineer, and they will tell you a different story. From FTTH optics to industrial applications, backbone transmission, and cloud data centers, fiber cables can last for decades under appropriate installation and handling. Even with the most skillful and diligent installation, commercially-produced.