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                                 EXHIBIT 99.1
                    PRESS RELEASE, DATED AUGUST 21, 1998.

FOR IMMEDIATE RELEASE                                 INVESTOR CONTACT:
- ---------------------                                    Suzanne DuLong
                                                      CIENA Corporation
                                                         (888) 243-6223
                                                           ir@ciena.com
                                                           ------------

                                                         PRESS CONTACT:
                                                           Denny Bilter
                                                      CIENA Corporation
                                                         (800) 921-1144



             CIENA ANNOUNCES AT&T DECISION RE 40 CHANNEL TESTING

LINTHICUM, MD - AUGUST 21, 1998 -- CIENA Corporation (NASDAQ: CIEN) today
announced that it had been informed this morning by AT&T that AT&T will not
pursue further evaluation of CIENA's DWDM systems.

In view of the timing of AT&T's decision, CIENA will adjourn its pending
stockholder meeting, scheduled for today, at which stockholders are to vote
on the proposed merger with Tellabs, Inc.  The stockholder meeting will be
reconvened on Wednesday, September 9 at 11:00 am Eastern time, at the
Company's Linthicum offices.

The Company indicated it would have further comments soon, but wanted to
disseminate news of the decision promptly.








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