Tucson, AZ-based GST Tucson Lightwave has started construction of a 26 route mile fiber-optic network that incorporates synchronous optical network equipment. Fujitsu Ltd. and Fujikura Ltd., both in Tokyo, are providing the electronics and cabling, respectively, for the project, which is expected to be completed in July. The first phase will connect downtown businesses and is 8 miles long. Phase two--18 route miles--will complete the ring around Tucson. A 75-route-mile third phase will extend the ring throughout the metropolitan area.