1

                   SECURITIES AND EXCHANGE COMMISSION
                         Washington, D.C. 20549
               _________________________________________

                             SCHEDULE 13D A

               Under the Securities Exchange Act of 1934

                           CIENA CORPORATION
                            (Name of Issuer)

                      Common Stock, $.01 Par Value
                     (Title of Class of Securities)

                              171779 10 1
                             (CUSIP Number)

                         Margaret Maxwell Zagel
                               Secretary
                             Tellabs, Inc.
                          4951 Indiana Avenue
                       Lisle, Illinois 60532-1698
                             (630) 378-8800
             (Name, Address and Telephone Number of Person
           Authorized to Receive Notices and Communications)

                              June 2, 1998
        (Date of Event which Requires Filing of This Statement)

    If the filing person has previously filed a statement on Schedule
13G to report the acquisition which is the subject of this Schedule 13D,
and is filing this schedule because of Rule 13d-1(b)(3) or (4), check
the following box:
(  ).

The information required on the remainder of this cover page shall not
be deemed to be "filed" for the purpose of Section 18 of the Securities
Exchange Act of 1934 (the "Act") or otherwise subject to the liabilities
of that section of the Act but shall be subject to all other provisions
of the Act (however, see the Notes).

                     (Continued on following pages)



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                             SCHEDULE 13D A

CUSIP No.  171779 10 1
    
1  NAME OF
   REPORTING
   PERSON

   Tellabs, Inc.
   
2  CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP

   (a) (  )   (b) (  )

3  SEC USE ONLY
   
4  SOURCE OF FUNDS

   NA
   
5  CHECK BOX IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED
   PURSUANT TO ITEMS 2(d) or 2(e)
   (a) (  )   (b) (  )

6  CITIZENSHIP OR PLACE OF ORGANIZATION

   Delaware

NUMBER OF        7     SOLE VOTING POWER
SHARES 
BENEFICIALLY     8     SHARED VOTING POWER
OWNED BY EACH          6,913,025*
REPORTING
PERSON WITH      9     SOLE DISPOSITIVE POWER

                10     SHARED DISPOSITIVE POWER
                       6,913,025*

11  AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON

    6,913,025*

12  CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES
    CERTAIN SHARES
    (a) (  )   (b) (  )



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13  PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11)

    6.8%

14  TYPE OF REPORTING PERSON

    CO

*Reporting Person disclaims beneficial ownership of all shares.

Item 1.		Security and Issuer
            -------------------
            The class of equity securities to which this Statement
            relates is the common stock, $.01 par value per share
            ("CIENA Common Stock"), of CIENA Corporation, a Delaware
            corporation ("CIENA").  CIENA's principal executive offices
            are located at 920 Elkridge Landing Road, Linthicum,
            Maryland 21090.

Item 2.		Identity and Background
            -----------------------
            This Statement is filed by Tellabs, Inc., a Delaware
            corporation ("Tellabs"), whose principal business address is
            4951 Indiana Avenue, Lisle, Illinois 60532-1698.  Tellabs'
            principal business is to design, manufacture, market and
            service voice and data transport and network access systems.
            During the past five years, Tellabs has not been convicted
            in a criminal proceeding (excluding traffic violations or
            similar misdemeanors), nor has it been a party to a civil
            proceeding of a judicial or administrative body of competent
            jurisdiction and as a result of such proceeding was or is
            subject to a judgment, decree or final order enjoining
            future violations of, or prohibiting or mandating activities
            subject to, federal or state securities laws or finding any
            violation with respect to such laws.

            Set forth below are the names, principal occupations and
            business addresses of the executive officers and directors
            of Tellabs.  With the exception of Jukka Harju, who is a
            citizen of Finland, each executive officer and director
            listed below is a citizen of the United States of America.
            During the past five years, none of the executive officers
            or directors has been convicted in a criminal proceeding
            (excluding traffic violations or similar misdemeanors), or
            has been a party to a civil proceeding of a judicial or
            administrative body of competent jurisdiction and as a
            result of such proceeding was or is subject to a judgment,



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            decree or final order enjoining future violations of, or
            prohibiting or mandating activities subject to, federal or
            state securities laws or finding any violation with respect
            to such laws.


Executive Officers of Tellabs:

NAME                        POSITION WITH TELLABS
- ----                        ---------------------

Michael J. Birck(1)         President, Chief Executive Officer and
                            Director, Tellabs, Inc.

Charles C. Cooney(1)        Vice President, Sales and Service,
                            Tellabs Operations, Inc.

J. Thomas Gruenwald(2)      Vice President, Strategic Resources, Tellabs
                            Operations, Inc.

Peter A. Guglielmi(2)       Executive Vice President, Chief Financial
                            Officer and Treasurer, Tellabs, Inc., and
                            Tellabs Operations, Inc. and Director,
                            Tellabs, Inc.

Jukka Harju(3)              Vice President and General Manager, Tellabs
                            Oy; Vice President, Tellabs International,
                            Inc.

Brian J. Jackman(1)         President, Tellabs Operations,Inc; Executive
                            Vice President and Director, Tellabs, Inc.

J. Peter Johnson(2)         Vice President, Finance and Treasury,
                            Assistant Secretary and Controller, Tellabs,
                            Inc., and Tellabs Operations, Inc.

John C. Kohler(2)           Vice President, Manufacturing, Tellabs
                            Operations, Inc.

Harvey R. Scull(1)          Vice President, Advanced Business
                            Development, Tellabs Operations, Inc.

Richard T. Taylor(1)        Senior Vice President and General Manager,
                            Digital Systems Division, Tellabs
                            Operations, Inc.

John E. Vaughan(1)          President, Tellabs International, Inc.;
                            Executive Vice President, Tellabs, Inc.



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Margaret Maxwell Zagel(1)     Vice President, General Counsel and
                            Secretary, Tellabs Operations, Inc.;
                            Secretary, Tellabs, Inc.

(1) The business address of this executive officer is 4951 Indiana
    Avenue, Lisle, Illinois 60532-1698.
(2) The business address of this executive officer is 1000 Remington
    Boulevard, Bolingbrook, Illinois 60440
(3) The business address of this executive officer is Sinikalliontie 7,
    FIN-02630, Espoo, Finland.



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Directors of Tellabs:
- --------------------
                              PRINCIPAL OCCUPATION, ADDRESS OF
NAME                          EMPLOYER AND BUSINESS ADDRESS OF DIRECTOR
- -----                         -----------------------------------------

Michael J. Birck              President and Chief Executive Officer of
                              Tellabs, Inc., 4951 Indiana Avenue Lisle,
                              Illinois 60532-1698.

John D. Foulkes, Ph.D.        Director of Engineering Studies (retired)
                              University of Puget Sound; Professor
                              (retired) University of Washington, 1256
                              S. Halsey Drive, Coupeville, Washington
                              98239.

Peter A. Guglielmi            Executive Vice President, Chief Financial
                              Officer and Treasurer, Tellabs, Inc., and
                              Tellabs Operations, Inc., 1000 Remington
                              Boulevard, Bolingbrook, Illinois 60440.

Brian J. Jackman              President, Tellabs Operations, Inc,
                              Executive Vice President, Tellabs, Inc.,
                              4951 Indiana Avenue Lisle, Illinois
                              60532-1698.

Frederick A. Krehbiel         Chief Executive Officer and Chairman of
                              the Board, Molex Incorporated, 2222
                              Wellington Court, Lisle, Illinois 60532.

Stephanie Pace Marshall,Ph.D. President, Illinois Mathematics and
                              Science Academy, 1500 W. Sullivan Road,
                              Aurora, Illinois 60506-1000.

William F. Souders            Chairman and Chief Executive Officer
                              (retired), Emery Air Freight Corporation,
                              formerly Executive Vice President, Xerox
                              Corporation, 100 First Stamford Place,
                              Suite 402, Stamford, Connecticut
                              06904-2340.



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Jan H. Suwinski               Professor of Strategy and Operations
                              Management-Johnson School, Cornell
                              University; Executive Vice President
                              (retired), Opto-Electronics Group, Corning
                              Incorporated; Chairman (retired) Siecor
                              Corporation, 451 Sheffield Road, Ithaca,
                              New York 14850.



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Item 3.		Source and Amount of Funds or Other Consideration
            -------------------------------------------------
            The Stockholder Agreements described in Item 4 of this
            Statement were entered into by Tellabs and the Stockholders
            listed in Item 4 as an inducement to Tellabs to enter into
            the Merger Agreement described in Item 4.  Except as set
            forth in the preceding sentence, Tellabs has paid no
            consideration in connection with entering into the
            Stockholder Agreements.

Item 4.		Purpose of Transaction
            ----------------------
            On June 2, 1998, Tellabs, Inc., a Delaware corporation
            ("Tellabs"), White Oak Merger Corp., a Delaware corporation
            and a wholly-owned subsidiary of Tellabs ("Sub"), and CIENA
            Corporation, a Delaware corporation ("CIENA"), entered into
            an Agreement and Plan of Merger (the "Merger Agreement"),
            providing for the merger of Sub with and into CIENA (the
            "Merger"), with CIENA surviving the Merger and becoming a
            wholly-owned subsidiary of Tellabs.  Pursuant to the Merger
            Agreement, by virtue of the Merger each outstanding share of
            CIENA Common Stock will be converted into the right to
            receive 1.0 share of common stock, $.01 par value per share,
            of Tellabs.  Pursuant to the Merger Agreement, the directors
            of Sub immediately prior to the consummation of the Merger
            will become the directors of CIENA upon the effectiveness of
            the Merger.  At the effective time of the Merger, in
            accordance with the Merger Agreement, the Third Restated
            Certificate of Incorporation of CIENA shall be amended to
            provide that the authorized capital stock of CIENA will be
            1,000 shares of CIENA Common Stock and the present Amended
            and Restated Bylaws of CIENA will remain in effect.  It is
            anticipated that, following the consummation of the Merger,
            the CIENA Common Stock will be delisted from the Nasdaq
            National Market and the CIENA Common Stock will be
            terminated from registration pursuant to Section 12(g)(4) of
            the Securities Exchange Act of 1934, as amended.  A copy of
            the Merger Agreement is included as Exhibit 1 hereto and the
            description of the Merger Agreement contained herein is
            qualified in its entirety by reference to such exhibit,
            which is incorporated herein by reference.



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            Concurrently with the execution of the Merger Agreement, in
            order to induce Tellabs to enter into the Merger Agreement,
            Billy Oliver, Patrick Nettles, Jon Bayless, Michael Zak,
            Harvey Cash, Clifford Higgerson and Stephen Bradley, who are
            all of the current directors of CIENA and Steve Chaddick and
            Lawrence Huang, who are key executive officers of CIENA
            (collectively, the "Stockholders") and who own (or have the
            right to acquire pursuant to outstanding options) an
            aggregate of 6,913,025 (approximately 6.8%) of the
            outstanding shares of CIENA Common Stock, entered into
            stockholder agreements (the "Stockholder Agreements") with
            Tellabs.

            The Stockholder Agreements provide, among other things,
            that: (a) at the stockholders meeting of CIENA to be held to
            approve and adopt the Merger Agreement (or at any
            adjournment thereof) or in any other circumstances upon
            which a vote, consent or other approval with respect to the
            Merger or the Merger Agreement is sought, the Stockholder
            shall vote (or cause to be voted) the shares of CIENA Common
            Stock owned by such Stockholder as of the date of the
            Stockholder Agreement and any other shares of capital stock
            of CIENA acquired by such Stockholder after the date of the
            Stockholder Agreement and during the term of the Stockholder
            Agreement (the "Subject Shares") in favor of the Merger, the
            adoption of the Merger Agreement and the approval of the
            terms thereof and each of the other transactions
            contemplated by the Merger Agreement; (b) at any meeting of
            stockholders of CIENA or at any adjournment thereof or in
            any other circumstances upon which the Stockholder's vote,
            consent or other approval is sought, the Stockholder shall
            vote (or cause to be voted) the Subject Shares against any
            amendment of the Third Restated Certificate of Incorporation
            of CIENA or the Amended and Restated Bylaws of CIENA which
            amendment would in any manner impede, frustrate, prevent or
            nullify the Merger, the Merger Agreement or any of the other
            transactions contemplated by the Merger Agreement or change
            in any manner the voting rights of any class of capital
            stock of CIENA; (c) the Stockholder agrees not to (i) sell
            (with certain limited exceptions), transfer, pledge, assign
            or otherwise dispose of (including by gift) (collectively,
            "Transfer"), or enter into any contract, option or other
            arrangement (including any profit-sharing arrangement) with
            respect to the Transfer of the Subject Shares to any person



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            or (ii) enter into any voting arrangement, whether by proxy,
            voting agreement or otherwise, in relation to the Subject
            Shares, and agrees not to commit or agree to take any of the
            foregoing actions; (d) the Stockholder shall not (i)
            directly or indirectly solicit, initiate, or knowingly
            encourage the submission of, any Takeover Proposal (as
            defined in the Merger Agreement) or (ii) directly or
            indirectly participate in any discussions or negotiations
            regarding, or furnish to any person any information with
            respect to, or take any other action to facilitate any
            inquiries or the making of any proposal that constitutes or
            may reasonably be expected to lead to, any Takeover
            Proposal; and (e) the Stockholder agrees to use all
            reasonable efforts to take, or cause to be taken, all
            actions, and to do, or cause to be done, and to assist and
            cooperate with Tellabs in doing, all things necessary,
            proper or advisable to consummate and make effective, in the
            most expeditious manner practicable, the Merger and the
            other transactions contemplated by the Merger Agreement.

            The obligations of the Stockholders under the Stockholder
            Agreements terminate upon the earlier of the termination of
            the Merger Agreement or the effective time of the Merger.

            A copy of the form of Stockholder Agreement entered into
            between Tellabs and each such Stockholder is filed as
            Exhibit 2 hereto, and the description of the Stockholder
            Agreements contained herein is qualified in its entirety by
            reference to such exhibit, which is incorporated herein by
            reference.

            In connection with the Merger Agreement, Tellabs and CIENA
            also entered into a Stock Option Agreement, dated as of June
            2, 1998 (the "Stock Option Agreement") pursuant to which
            CIENA granted Tellabs an option to purchase up to 19.9% of
            CIENA's Common Stock upon the occurrence of certain
            specified events, including, but not limited to, the
            acquisition of 20% or more of CIENA's Common Stock by any
            party other than Tellabs.

            Further details regarding the Stock Option Agreement are
            contained in the copy of the Stock Option Agreement filed as
            Exhibit 3 hereto and the description of the Stock Option
            Agreement contained herein is qualified in its entirety by
            reference to such exhibit, which is incorporated herein by
            reference.



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Item 5.     Interest in Securities of the Issuer.
            ------------------------------------
            (a) - (c)  By reason of the Stockholder Agreements, Tellabs
                       may be deemed to be the beneficial owner of, in
                       the aggregate, 6,913,025 shares (the "Shares") of
                       CIENA Common Stock and may be deemed to have
                       shared power to vote or direct the vote of the
                       Shares or shared power to dispose or direct the
                       disposition of the Shares.  The Shares represent
                       approximately 6.8% of the outstanding shares of
                       CIENA Common Stock, based upon the number of
                       shares outstanding as of May 28, 1998.  By virtue
                       of the limited nature of the Stockholder
                       Agreements, Tellabs expressly disclaims
                       beneficial ownership of the Shares. Except as
                       described in this Schedule 13D A, neither Tellabs
                       nor, to the best knowledge of Tellabs, any of the
                       persons listed in Item 2 above beneficially owns
                       any shares of CIENA Common Stock.  Except as
                       described in this Schedule 13D A, neither Tellabs
                       nor, to the best of its knowledge, any of the
                       persons listed in Item 2 above has effected any
                       transactions in CIENA Common Stock during the
                       past 60 days.

            (d) Not applicable.

            (e) Not applicable



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Item 6.     Contracts, Arrangements, Understanding or Relationships with
            Respect to Securities of the Issuer.
            -----------------------------------
            As described in Item 4, Tellabs presently anticipates that
            it will acquire the entire equity interest in CIENA pursuant
            to the Merger Agreement.

            Other than the Merger Agreement, the Stockholder Agreements
            and the Stock Option Agreement described in Item 4 and
            attached as Exhibits to this Statement, to the best
            knowledge of Tellabs, there are no contracts, arrangements,
            understandings or relationships (legal or otherwise) between
            the persons listed in Item 2 of this Statement and any
            person with respect to CIENA Common Stock.

Item 7.		Material to be Filed as Exhibits.
            --------------------------------
            1   Agreement and Plan of Merger dated as of June 2, 1998
                among Tellabs, Inc., White Oak Merger Corp. and CIENA
                Corporation (Incorporated by reference to Exhibit 2.2 of
                Tellabs, Inc.'s Current Report on Form 8-K (filed on
                June 4, 1998)).
                
            2   Form of Stockholder Agreement dated as of June 2, 1998
                entered into between Tellabs, Inc. and certain
                stockholders of CIENA Corporation (including a schedule
                listing each such stockholder and the number of shares
                of common stock of CIENA Corporation owned by such
                stockholder as set forth in the Stockholder Agreement
                entered into by such stockholder).

           3   Stock Option Agreement between Tellabs, Inc. and CIENA
               Corporation dated June 2, 1998 (incorporated by reference
               to Exhibit 2.3 of Tellabs, Inc.'s Current Report on Form
               8-K (filed on June 4, 1998).



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SIGNATURE

After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true,
complete and correct.


                                   TELLABS, INC.

Dated:  July 9, 1998              By:  /s/ Margaret Maxwell Zagel
                                        --------------------------
                                        Margaret Maxwell Zagel
                                        Secretary




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EXHIBIT INDEX
- -------------

Exhibit No.	Description
- -----------------------
1   Agreement and Plan of Merger dated as of June 2, 1998 among Tellabs,
    Inc., White Oak Merger Corp. and CIENA Corporation (Incorporated by
    reference to Exhibit 2.2 of Tellabs, Inc.'s Current Report on Form
    8-K (filed on June 4, 1998)).

2   Form of Stockholder Agreement dated as of June 2, 1998 entered into
    between Tellabs, Inc. and certain stockholders of CIENA Corporation
    (including a schedule listing each such stockholder and the number
    of shares of common stock of CIENA Corporation owned by such
    stockholder as set forth in the Stockholder Agreement entered into
    by such stockholder).

3   Stock Option Agreement between Tellabs, Inc. and CIENA Corporation
    dated June 2, 1998 (incorporated by reference to Exhibit 2.3 of
    Tellabs, Inc.'s Current Report on Form 8-K (filed on June 4, 1998).



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                                                   Exhibit 2


                     FORM OF STOCKHOLDER AGREEMENT


STOCKHOLDER AGREEMENT, dated as of June 2, 1998 (this "Agreement"), by
the undersigned stockholder (the "Stockholder") of CIENA Corporation, a
Delaware corporation (the "Company"), for the benefit of Tellabs, Inc.,
a Delaware corporation ("Parent").

                                RECITALS
                                --------

WHEREAS, Parent, White Oak Merger Corp., a Delaware corporation and a
direct wholly owned subsidiary of Parent ("Sub"), and the Company are
entering into an Agreement and Plan of Merger, dated as of June 2, 1998
(the "Merger Agreement"), whereby, upon the terms and subject to the
conditions set forth in the Merger Agreement, each issued and
outstanding share of Common Stock, par value $.01 per share, of the
Company ("Company Common Stock"), not owned directly or indirectly by
Parent or the Company, will be converted into shares of Common Stock,
par value $.01 per share, of Parent ("Parent Common Stock");

WHEREAS, the Stockholder owns of record and/or holds stock options to
acquire (whether or not vested) that number of shares of Company Common
Stock appearing on the signature page hereof (such shares of Company
Common Stock, together with any other shares of capital stock of the
Company acquired by such Stockholder after the date hereof and during
the term of this Agreement, being collectively referred to herein as the
"Subject Shares"); and

WHEREAS, as a condition to its willingness to enter into the Merger
Agreement, Parent has required that the Stockholder agree, and in order
to induce Parent to enter into the Merger Agreement the Stockholder has
agreed, to enter into this Agreement.

NOW, THEREFORE, in consideration of the promises and the mutual
covenants and agreements set forth herein, the Stockholder agrees as
follows:



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1.  Covenants of Stockholder.
    ------------------------
    Until the termination of this Agreement in accordance with Section
    4, Stockholder agrees as follows:

    (a) At the Company Stockholder Meeting (or at any adjournment
        thereof) or in any other circumstances upon which a vote,
        consent or other approval with respect to the Merger and the
        Merger Agreement is sought, the Stockholder shall vote (or cause
        to be voted) the Subject Shares in favor of the Merger, the
        adoption of the Merger Agreement and the approval of the terms
        thereof and each of the other transactions contemplated by the
        Merger Agreement.

    (b) At any meeting of stockholders of the Company or at any
        adjournment thereof or in any other circumstances upon which the
        Stockholder's vote, consent or other approval is sought, the
        Stockholder shall vote (or cause to be voted) the Subject Shares
        against any amendment of the Company's Third Restated
        Certificate of Incorporation, as amended, or Amended and
        Restated By-Laws involving the Company or any of its
        Subsidiaries, which amendment would in any manner impede,
        frustrate, prevent or nullify the Merger, the Merger Agreement
        or any of the other transactions contemplated by the Merger
        Agreement or change in any manner the voting rights of any class
        of capital stock of the Company. The Stockholder further agrees
        not to commit or agree to take any action inconsistent with the
        foregoing.

    (c) The Stockholder agrees not to (i) sell (except to the extent set
        forth in Annex A hereto), transfer, pledge, assign or otherwise
        dispose of (including by gift) (collectively, "Transfer"), or
        enter into any contract, option or other arrangement (including
        any profit-sharing arrangement) with respect to the Transfer of
        the Subject Shares to any person or (ii) enter into any voting
        arrangement, whether by proxy, voting agreement or otherwise, in
        relation to the Subject Shares, and agrees not to commit or
        agree to take any of the foregoing actions.



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    (d) The Stockholder shall not, nor shall the Stockholder permit any
        affiliate, director, officer, employee, investment banker,
        attorney or other advisor or representative of the Stockholder
        to, (i) directly or indirectly solicit, initiate or knowingly
        encourage the submission of, any Takeover Proposal or (ii)
        directly or indirectly participate in any discussions or
        negotiations regarding, or furnish to any person any information
        with respect to, or take any other action to facilitate any
        inquiries or the making of any proposal that constitutes or may
        reasonably be expected to lead to, any Takeover Proposal.

    (e) The Stockholder shall use the Stockholder's reasonable best
        efforts to take, or cause to be taken, all actions, and to do,
        or cause to be done, and to assist and cooperate with Parent in
        doing, all things necessary, proper or advisable to support and
        to consummate and make effective, in the most expeditious manner
        practicable, the Merger and the other transactions contemplated
        by the Merger Agreement.

2.  Representations and Warranties.
    ------------------------------
    The Stockholder represents and warrants to Parent as follows:

    (a) The Stockholder is the record and beneficial owner of, and has
        good and marketable title to, the Subject Shares.  The
        Stockholder does not own, of record or beneficially, any shares
        of capital stock of the Company other than the Subject Shares.
        The Stockholder has the sole right to vote, and the sole power
        of disposition with respect to, the Subject Shares, and none of
        the Subject Shares is subject to any voting trust, proxy or
        other agreement, arrangement or restriction with respect to the
        voting or disposition of such Subject Shares, except as
        contemplated by this Agreement.

    (b) This Agreement has been duly executed and delivered by the
        Stockholder.  Assuming the due authorization, execution and
        delivery of this Agreement by Parent, this Agreement constitutes
        the valid and binding agreement of the Stockholder enforceable
        against the Stockholder in accordance with its terms, except as
        may be limited by applicable bankruptcy, insolvency,
        reorganization, moratorium and other similar laws of general
        application which may affect the enforcement of creditors'
        rights generally and by general equitable principles.  The
        execution and delivery of this Agreement by the Stockholder does
        not and will not conflict with any agreement, order or other
        instrument binding upon the Stockholder, nor require the



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        Stockholder to make or obtain any regulatory filing or approval
        other than filings, if any, required pursuant to the Securities
        Exchange Act of 1934, as amended.

3.  Affiliate Letter.
    ----------------
    The Stockholder agrees to execute and deliver on a timely basis an
    Affiliate Letter in the form of Exhibit 5.5(a) to the Merger
    Agreement, when and if requested by Parent.

4.  Termination.
    -----------
    The obligations of the Stockholder hereunder shall terminate upon
    the earlier of the termination of the Merger Agreement pursuant to
    Section 7.1 thereof or the Effective Time.

5.  Further Assurances.
    ------------------
    The Stockholder will, from time to time, execute and deliver, or
    cause to be executed and delivered, such additional or further
    consents, documents and other instruments as Parent may reasonably
    request for the purpose of effectively carrying out the transactions
    contemplated by this Agreement.

6.  Successors, Assigns and Transferees Bound.
    -----------------------------------------
    Any successor, assignee or transferee (including a successor,
    assignee or transferee as a result of the death of the Stockholder,
    such as an executor or heir) shall be bound by the terms hereof, and
    the Stockholder shall take any and all actions necessary to obtain
    the written confirmation from such successor, assignee or transferee
    that it is bound by the terms hereof.

7.  Remedies.
    --------
    The Stockholder acknowledges that money damages would be both
    incalculable and an insufficient remedy for any breach of this
    Agreement by it, and that any such breach would cause Parent
    irreparable harm.  Accordingly, the Stockholder agrees that in the
    event of any breach or threatened breach of this Agreement, Parent,
    in addition to any other remedies at law or in equity it may have,
    shall be entitled, without the requirement of posting a bond or
    other security, to equitable relief, including injunctive relief and
    specific performance.



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8.  Severability.
    ------------
    The invalidity or unenforceability of any provision of this
    Agreement in any jurisdiction shall not affect the validity or
    enforceability of any other provision of this Agreement in such
    jurisdiction, or the validity or enforceability of any provision of
    this Agreement in any other jurisdiction.  If in the opinion of
    Parent's independent accountants, any provision hereof would cause
    the Merger to be ineligible for "pooling of interest" accounting
    treatment, it shall be deemed to be ineffective and inapplicable.

9.  Amendment.
    ---------
    This Agreement may be amended only by means of a written instrument
    executed and delivered by both the Stockholder and Parent.

10. Governing Law.
    -------------
    This Agreement shall be governed by, and construed in accordance in
    accordance with, the laws of the State of Delaware, regardless of
    the laws that might otherwise govern under applicable principles of
    conflicts of laws thereof.

11. Capitalized Terms.
    -----------------
    Capitalized terms used in this Agreement that are not defined herein
    shall have such meanings as set forth in the Merger Agreement.

12. Counterparts.
    ------------
    For the convenience of the parties, this Agreement may be executed
    in counterparts, each of which shall be deemed an original, but all
    of which together shall constitute one and the same instrument.



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13. No limitation on Actions of the Stockholder as Director.
    -------------------------------------------------------
    In the event the Stockholder is a director of the Company,
    notwithstanding anything to the contrary in this Agreement, nothing
    in this Agreement is intended or shall be construed to require the
    Stockholder to take or in any way limit any action that the
    Stockholder may take to discharge the Stockholder's fiduciary duties
    as a director of the Company.


                              [______________________________]*
                               Name:

                               Number of shares of Company Common
                               Stock owned on the date hereof:
                               _____________

Accepted and Agreed to
as of the date set forth above:

TELLABS, INC.


By:                                          
   Name:
   Title:




 7


                    The following ANNEX A should be
             attached to Stockholder Agreements signed by:


                             Lawrence Huang
                             Steve Chaddick



 8


                                ANNEX A



The stockholder may sell up to ten (10) percent of the Subject Shares in
compliance with applicable laws and subject to the Affiliate Letter
referred to in Section 3 of this Agreement.



 9


                    The following ANNEX A should be
             attached to Stockholder Agreements signed by:

                            Patrick Nettles
                              Jon Bayless
                            Stephen Bradley
                              Harvey Cash
                              Billy Oliver
                           Clifford Higgerson
                              Michael Zak


 10


                                ANNEX A



Stockholder may not sell any of the Subject Shares.


 

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                                Schedule
                                --------

List of Parties to the Stockholder Agreements and Shares Held as
Described in Exhibit 2 to this Schedule 13D A

              Stockholder               Shares Currently Owned(1)
              -----------               ----------------------

              Jon Bayless                      181,794
              Stephen Bradley                   30,000
              Harvey Cash                      177,500
              Steve Chaddick                 1,025,250(2)
              Clifford Higgerson               286,658
              Lawrence Huang                 1,001,250(2)
              Patrick Nettles                3,927,010
              Billy Oliver                      72,500
              Michael Zak                      211,063


(1) The number of shares includes stock options and is as reported by
    each stockholder in his respective Stockholder Agreement.

(2) Messrs. Chaddick and Huang have the right to sell up to ten (10)
    percent of the Subject Shares subject to complying with applicable
    laws and their Affiliate Letter.