SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                                    FORM 8-K
                                 CURRENT REPORT
                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934



                                December 22, 2003
                                -----------------
                Date of Report (Date of earliest event reported)



                                CIENA Corporation
                                -----------------
             (Exact name of registrant as specified in its charter)


           Delaware                    0-21969                     23-2725311
 (State or other jurisdiction   (Commission File No.)            (IRS Employer
      of incorporation)                                     Identification No.)

                 1201 Winterson Road, Linthicum, Maryland 21090
                 ----------------------------------------------
               (Address of principal executive offices) (Zip Code)



               Registrant's telephone number, including area code:
                                 (410) 865-8500
                                  -------------


                                 Not applicable
                                 --------------
          (Former name or former address, if changed since last report)


                             Exhibit Index on Page 2






Item 5. Other Events and Regulation FD Disclosure. On December 22, 2003, CIENA Corporation issued the press release, attached hereto as Exhibit 99.1, concerning the redemption of all the outstanding 5% Convertible Subordinated Notes due October 15, 2005 The press release is incorporated herein by this reference. Item 7. Financial Statements and Exhibits. (c) Exhibits. 99.1 Press Release, issued December 22, 2003.

SIGNATURES Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned thereunto duly authorized. CIENA CORPORATION Date: December 22, 2003 By: --------------------------------------------- Russell B. Stevenson, Jr. Senior Vice President, General Counsel and Secretary

                                                                    Exhibit 99.1

          CIENA Completes Redemption of 5% Convertible Notes Originally
                          Issued by ONI Systems Corp.

    LINTHICUM, Md.--(BUSINESS WIRE)--Dec. 22, 2003--CIENA(R)
Corporation (NASDAQ:CIEN), a leading global provider of innovative
network solutions, today announced that it had completed the
redemption of all the outstanding 5% Convertible Subordinated Notes
due October 15, 2005 originally issued by ONI Systems Corp. The notes
were assumed by CIENA in its acquisition of ONI in June 2002. The
principal amount of the notes redeemed was approximately $48 million.
On the redemption date, December 19, 2003, CIENA paid holders 102% of
the outstanding principal amount of the notes plus accrued interest.
    The Company expects to record a book loss of approximately $8.2
million related to the extinguishment of this debt due to the fact
that the accreted book value of the notes will be less than the
purchase price. The Company will use its cash and cash equivalents,
and short-term investments to fund the redemption.
    By redeeming the notes, CIENA will reduce its annual interest
expense and eliminate the need to repay the debt at maturity in 2005.
The redemption should result in a net cash savings to the Company of
approximately $2 million over the remaining two-year life of the
notes, based on the spread between the interest payments on the notes
and the income generated from investing the principal at current rates
of return.

    ABOUT CIENA

    CIENA Corporation delivers innovative network solutions to the
world's largest service providers and enterprises, increasing the
cost-efficiency of current services while enabling the creation of new
carrier-class data services built upon the existing network
infrastructure. Additional information about CIENA can be found at
www.ciena.com.

    NOTE TO INVESTORS

    This press release contains certain forward-looking statements
based on current expectations, forecasts and assumptions of CIENA (the
Company) that involve risks and uncertainties. Forward-looking
statements in this release, including the expected net cash savings to
CIENA, are based on information available to the Company as of the
date hereof. The Company's actual results could differ materially from
those stated or implied in such forward-looking statements, due to
risks and uncertainties associated with the Company's business, which
include the risk factors disclosed in the Company's Report on Form
10-K filed with the Securities and Exchange Commission on December 11,
2003. Forward looking statements include statements regarding the
Company's expectations, beliefs, intentions or strategies regarding
the future and can be identified by forward looking words such as
"anticipate," "believe," "could," "estimate," "expect," "intend,"
"may," "should," "will," and "would" or similar words. The Company
assumes no obligation to update the information included in this press
release, whether as a result of new information, future events or
otherwise.


    CONTACT: CIENA Corporation
             Press Contacts:
             Denny Bilter or Aaron Graham, 877-857-7377
             pr@ciena.com
                 or
             Investor Contacts:
             Suzanne DuLong or Jessica Towns, 888-243-6223
             ir@ciena.com