Tyco Submarine Systems Ltd., a wholly owned subsidiary of Tyco International Ltd. of Hamilton, Bermuda, has begun construction of an undersea fiber telecommunications network. The system, which is to be known as the TyCom Global Network, will connect 25 cities, including New York, London, Hong Kong, Tokyo, Tel Aviv, Israel, and St. Petersburg, Russia. Tyco will employ its own cable and components, build the operating stations and telehouses, and install and maintain the 85,000-km network with its 13-vessel fleet. The trans-Atlantic network is scheduled for completion by the end of 2001. Tyco plans to complete the trans-Pacific and European portions the following year.