Lucent has acquired about a dozen data-networking companies in the past 18 months to bolster its ability to develop equipment that delivers data traffic more efficiently. On Thursday, the company completed its $20 billion acquisition of networking-equipment maker Ascend Communications Inc.

The Nexabit deal was widely anticipated, though the price came in above expectations, which were for a price tag in the $600 million to $800 million range. The acquisition talks were first reported in the New York Times.Lucent said it will exchange about 14 million Lucent common shares for closely held Nexabit, Marlborough, Mass. Lucent's closed Thursday at $64, down $1.6875, on the New York Stock Exchange.

Lucent is one of the oldest suppliers of traditional equipment used by telephone companies, but it needs Ascend and other equipment companies who make Internet-stylecommunications technology to help it remain competitive as phone companies move their networks from circuit-switch technology, which moves voice and data traffic by tying up an entire line, to packet technology that sends the information more cheaply by breaking it into bits.

These IP-based networks allow lines to carry commingled voice, data and cable traffic. The transaction - which is seen closing by the end of July - isn't expected to affect Lucent's earnings in fiscal 1999 or 2000. Lucent will account for the acquisition as a pooling of interests.

Nexabit chief executive Mukesh Chatter will join Lucent as vice-president of Lucent's internetworking systems group.