Lightning protection for straight-type optical cable lines: ①In-office grounding mode, the metal parts in the optical cable should be connected at the joints, so that the reinforcing core, moisture-proof layer, and armor layer of the relay section of the optical cable . Lightning protection for straight-type optical cable lines: ①In-office grounding mode, the metal parts in the optical cable should be connected at the joints, so that the reinforcing core, moisture-proof layer, and armor layer of the relay section of the optical cable . Although the signals in fiber cables are optical signals, most of the outdoor optical cables using reinforced cores or armored optical cables are easy to get damaged under lightning because of the metal protective layer inside the cable. Therefore, it is important to build a lightning protection. However, because the optical cable has a reinforced core, it is particularly The directly buried optical cable has an armor layer, so when the optical cable line is struck by lightning, the optical cable can also be burned or damaged. So, how do we prevent lightning damage in fiber optic cable. Recommendation ITU-T L. 101 describes characteristics, construction and test methods of optical fibre cables for buried application. However, because fiber optic cable has strengthened core, especially the direct-buried fiber optic cable has armoring layer. Effective protection is only guar-anteed when surge voltages are reduced in stages as part of a lightning protection zone concept. Our light-ning and surge voltage protection systems are per-fectly matched to one another and to the requirements in the different zones – from the air-termination. Lightning poses several significant risks to fiber optic cables and the networks they support: Cable Damage: A lightning strike can directly damage fiber optic cables, causing signal loss, equipment failure, or complete network outages. Induced Voltages: Electromagnetic induction from nearby.