MURRAY HILL, NJ, June 29 -- Lucent Technologies Inc. announced that it will buy start-up Nexabit Networks for about $900 million in stock in a move to expand its offerings of high-speed networking equipment. Lucent plans to issue about 14 million shares of common stock as part of the purchase. The company expects the deal, which will be accounted as a pooling of interests, to close by July 31 and to have no effect on its earnings in fiscal 1999 and fiscal 2000. The communications revolution is fueling tremendous demand for more bandwidth in core networks, said Curt Sanford, president of Lucent's InterNetworking Systems. This merger gives Lucent not only a leading product for ultra high-speed Internet Protocol core networks, but a terrific lead in delivering terabit-speed switch/routers that connect directly to optical networking systems.