NEW YORK, Dec. 21 -- In a move to get a foothold in the urban telecommunications market, Ciena Corp. said that it would buy Cyras Systems Inc. for $2.0 billion worth of Ciena stock. As a result of the deal Ciena, a maker of telecommunications equipment, will obtain Cyrus's K2 system, which can extend high-speed fiber optic networks to individuals and businesses located in cities. The K2 system is currently being tested and is slated for shipments in the first half of 2001, said Ciena. It's strategically a very good move for the company and puts them head to head with (Cisco), said Raj Srikanth, a fiber optic equipment analyst with Deutsche Banc Alex Brown.