Cable technology is changing the shape of the world we live in, says Steve Homer
Cable & Wireless has just started laying the world's longest undersea cable. Among other things, it should make your phone calls sound better.

If you made an international call at Christmas and it was clear as a bell, it was almost certainly a call carried across the Atlantic on a cable. If you had a speech delay or an off-putting echo, that was a satellite connection. Submarine cables are the unsung heroes of recent telecommunications revolutions.

Ever since Telstar, the communications satellite that was launched in 1962, satellite technology has seemed sexy. Nearly everyone believes transatlantic phone calls are carried over satellite links and that cables are ancient technology. Well, they are. The first international submarine cable was laid across the Channel in 1850. Astonishingly, the first transatlantic cable (for the telegraph) was also laid in the 1850s. But since the arrival of optical fibre technology, submarine cables have enjoyed a resurgence. A few years ago, the transatlantic telephone traffic was about 50-50 between cable and satellite. Now it is more like 70-30 in cable's favour.

In fact, there has never been so much cable-laying going on and it looks set to increase. It is not just our desire to chat that is driving the cable business; services such as video conferencing, on-demand video news services and the Internet are beginning to gobble up telephone capacity. Telephone companies believe we are seeing just the beginning of a massive new surge in demand.

That is why six major institutions have joined together to build Flag, the rather grandly named Fibre Optic Link Around the Globe, which Cable & Wireless Marine started laying just after the new year.

Flag will stretch from Cornwall to Japan via Spain, Italy, Egypt, India, Thailand, Hong Kong and Korea with side connections to the United Arab Emirates, Malaysia and China. It is a massive project that will take two years to build and cost in the region of $1.2bn.

The reason it is being built is simple, says John Mercogliano, Flag's vice-president, Europe. There is more than 20 times the telecommunications cable capacity going between North America and Europe and North America and the Far East as there is between Europe and the Far East. The business is there, it is just not being properly served. He likens the building of Flag to the building of the M4: "This is a major infrastructure project. Just as the M4 brought a lot of jobs and prosperity to Wales, so Flag will have a major impact on all the economies it connects."

Flag is due to start operation in September 1997. In that time ships will have laid 28,000 kilometres (17,000 miles) of cable. Using just four tiny glass fibres the cable will be able to carry about 600,000 simultaneous telephone conversations.

Flag is not only the longest cable ever built, it is the most sophisticated. One thing is sure: it will not be the last.