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. An outdoor steel-armored fiber optic cable with a PE sheath can last for more than 25 years under field conditions. But ask any veteran network engineer, and they will tell you a different story. 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. Optical fibre cables are designed and manufactured to ensure stable and consistent fibre performances for a predicted operating lifetime of at least 25 years under the prevailing environmental conditions (underground and/or aerial installation).
