Tokyo, Aug 26 (ANI): Tokyo, the mega city, is known for its best telecommunication services. The secret lies in these tunnels, which has an underground fiber network, known as "Toudo" in Japanese. It spans a distance of 290 kilometers in Tokyo, and a total distance of 650 kilometers nationwide. The deepest tunnel stood 50 meters below the ground level. Japan's first telecom tunnel system constructed nearly a century ago in 1926 is still in use. The Tunnel securely conceals telecom cables, both copper wires used for generations, and thin optical fiber cables that can transmit grater amount of data. Many companies are now adopting cloud computing and expanding to utilize data centers. The aerial wire is one of the ways to connect cables, but it has weakness against storms and natural disasters. Pipelines are much secure in underground, but it has very limited in extensibility.