Between them, Japan's ten regional electricity suppliers own the second-largest fibre-optic network in the country, measuring 160, 000 kilometres and growing.

ECONOMIST: Japanese Telecoms

The system consists of sensors fitted on cables throughout the network, both overhead and underground, measuring current and conductor temperature.

FORBES: GE Gobbles Up More of the Smart Grid

These include the international seismic monitoring network, the international array of sea level measuring stations (the Global Sea Level Observing System, the Global Telecommunication System of the World Meteorological Organization and associated public geostationary satellites) and the internet.

UNESCO: & CTBTO: Working together to issue timely alerts