Most Fiber cables don't Need to be Replaced. If installed and protected correctly against technical and environmental conditions, they can last: 25–50 years (outdoor plant infrastructure, long-haul wiring) 15–30 years (indoor building wiring systems) 10–20 years (FTTH plant drop. Most Fiber cables don't Need to be Replaced. The foundation of an. Fiber optic cables have a reputation for their prolonged lifespan, low maintenance need, and dependable quality. From FTTH optics to industrial applications, backbone transmission, and cloud data centers, fiber cables can last for decades under appropriate installation and handling. So, how often. Prysmian, leader in the energy transition and digital transformation, announces results of new and rigorous long-term ageing testing on the Sirocco family of cables, proving expected lifetime of more than 50 years, allowing operators to calculate the life cycle analysis of their networks over an. Usually, for the useful life of the terrestrial fiber optic cables, it is expected that there will be more than 20 years of safe use. While, for submarine fiber optic cables, progress has been made in demanding that their life expectancy increase to more than 25 years, with an average of 10 years. We proposed a novel method for predicting the service life of optical cables based on the Autoformer model combined with the calculation method. But ask any veteran network engineer, and they will tell you a different story. Others, installed in the 1990s, are still running.