VOTING AGREEMENT

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Exhibit 99.1

VOTING AGREEMENT

        THIS VOTING AGREEMENT, is made and entered into as of this 17th day of January, 2005 (the " Agreement "), by and among McDATA Corporation, a Delaware corporation (" Parent "); Condor Acquisition, Inc., a Minnesota corporation and a wholly owned subsidiary of Parent (" Merger Sub "); Computer Network Technology Corporation, a Minnesota corporation (the " Company "); Thomas G. Hudson; Thomas G. Hudson 2004 Grantor Retained Annuity Trust dated October 15, 2004, Thomas G. Hudson, Trustee; Erwin A. Kelen; John A. Rollwagen; Patrick W. Gross; Lawrence A. McLernon; Kathleen B. Earley; Bruce J. Ryan.; Gregory T. Barnum; Mark R. Knittel; Edward J. Walsh and Robert R. Beyer (each a " Shareholder " and collectively, the " Shareholders ").

RECITALS

        A.    Contemporaneously with the execution and delivery of this Agreement, Parent, Merger Sub and the Company are entering into an Agreement and Plan of Merger, dated as of the date hereof (the " Merger Agreement "), which provides for, upon the terms and subject to the conditions set forth therein, a business combination between Parent and the Company by means of a merger of Merger Sub with and into the Company (the " Merger ").

        B.    As of the date hereof, each Shareholder beneficially owns the number of shares of common stock, par value $0.01 per share, of the Company set forth opposite such Shareholder's name on Schedule I hereto (all such shares so owned and which may hereafter be acquired by such Shareholder prior to the termination of this Agreement, whether upon the exercise of options, conversion of notes, underlying restricted stock units or deferred stock units, or by any other means of purchase, dividend, distribution or otherwise, being referred to herein as such Shareholder's " Shares ").

        C.    In connection with the Merger and pursuant to the terms of the Merger Agreement, each Shareholder has agreed to grant Parent an irrevocable proxy to vote the Shareholder's Shares in favor of the adoption of the Merger Agreement and the approval of the terms thereof and each of the other transactions contemplated by the Merger Agreement.

        D.    Upon the consummation of the Merger, the Shareholders will become owners of shares of Common Stock of Parent (the " Parent Shares "), and, in connection therewith, the Shareholders will agree to certain restrictions on the transfer of the Parent Shares.

        E.    As a condition to their willingness to enter into the Merger Agreement, Parent and Merger Sub have requested that the Shareholders enter into this Agreement.

        F.     In order to induce Parent and Merger Sub to enter into the Merger Agreement, the Shareholders are willing to enter into this Agreement.

        NOW, THEREFORE, in consideration of the foregoing and the mutual covenants and agreements herein contained, and intending to be legally bound hereby, the parties hereto hereby agree as follows:

ARTICLE I
VOTING AGREEMENT

         1.1      Voting of Shares.     From the date hereof until the termination of this Agreement, at any meeting of the shareholders of the Company, however called, and in any action by consent of the shareholders of the Company, each Shareholder shall vote such Shareholder's Shares (i) in favor of the Merger, the Merger Agreement (as amended from time to time pursuant to the terms thereof) and all other transactions contemplated thereby, (ii) against any Acquisition Proposal or any negotiations or discussions with respect to an Acquisition Proposal and against any proposal for action or agreement that would result in a breach of any covenant, representation or warranty or any other obligation or agreement of the Company under the Merger Agreement, any change in the directors of the Company, any change in the present capitalization of the Company or any amendment to the Company's Articles

of Incorporation or Bylaws, which in the case of each of the matters referred to in this clause (ii) could reasonably be expected to impede, interfere with, delays, postpones or materially adversely affect the transactions contemplated by the Merger Agreement or the likelihood of such transactions being consummated, and (iii) in favor of any other matter necessary for consummation of the transactions contemplated by the Merger Agreement and related agreements which is considered at any such meeting of shareholders or in such consent, and in connection therewith to execute any documents which are necessary in order to effectuate the foregoing, including the ability for Parent or its nominees to vote such Shares directly.

         1.2      Irrevocable Proxy.     Each Shareholder hereby agrees to deliver to Parent a duly executed proxy in the form attached hereto as Exhibit A concurrently with the execution and delivery of this Agreement (the " Proxy "), such Proxy to cover the Shares in respect of which Shareholder is entitled to (i) vote at each meeting of the shareholders of the Company (including, without limitation, each written consent in lieu of a meeting) in favor of the Merger and the adoption and approval of the Merger Agreement and all transactions contemplated thereby, and (ii) demand that the Secretary or any other appropriate officer of the Company call a special meeting of the shareholders of the Company for the purpose of considering the Merger, the Merger Agreement and all other transactions contemplated thereby. Each Shareholder hereby revokes any and all prior proxies or powers of attorney given by such Shareholder with respect to the Shares. The Proxy shall be automatically terminate and be of no further force or effect upon any termination of this Agreement.

         1.3      No Proxies for or Transfers of Shareholder Shares.     Except as contemplated by the terms of this Agreement, from the date hereof until the termination of this Agreement, each Shareholder hereby agrees that such Shareholder shall not, without the prior written consent of Parent, which may be withheld in the sole discretion of Parent, directly or indirectly, (i) grant any proxies or enter into any voting trust or other agreement, arrangement or understanding with respect to the voting of any such Shareholder's Shares, or (ii) sell, assign, transfer, encumber, pledge or otherwise dispose of, or enter into any contract, option or other agreement, arrangement or understanding with respect to the direct or indirect sale, assignment, transfer, encumbrance, pledge or other disposition of, any of such Shareholder's Shares. Each Shareholder hereby agrees such Shareholder shall not seek or solicit any such sale, assignment, transfer, encumbrance, pledge or other disposition or any such contract, option or other agreement, arrangement or understanding and agrees to notify Parent promptly (but in any event, within 24 hours), and to provide all details requested by Parent, if such Shareholder shall be approached or solicited, directly or indirectly, by any person with respect to any of the foregoing. Notwithstanding any other provision of this Section 1.3, each Shareholder may sell or otherwise assign, with or without consideration, an unlimited amount of such Shareholder's Shares to any spouse or member of his immediate family, or to a custodian, trustee (including a trustee of a voting trust), executor or other fiduciary for the account of his spouse or members of his immediate family, or to a trust for himself, or to a charitable remainder trust, or any affiliate, member or limited or general partner of such Shareholder, or to any entity that is wholly owned by members of such Shareholder's immediate family, provided that each such transferee or assignee, prior to the completion of the sale, transfer or assignment shall have executed and delivered to Parent documents assuming the obligations of such Shareholder under this Agreement with respect to the transferred securities, such documents to be satisfactory to Parent in its sole discretion. Further notwithstanding any other provision of this Section 1.3, each Shareholder may dispose of shares of restricted stock to the Company to pay taxes upon vesting and issuance of such shares of restricted stock by the Company to each Shareholder.

         1.4      Stop Transfer.     During the term of this Agreement, no Shareholder shall request that the Company register the transfer (book-entry or otherwise) of any certificate or uncertificated interest representing any of such Shareholder's Shares, unless such transfer is made in compliance with this Agreement.

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         1.5      Notification.     If any Shareholder becomes aware of an Acquisition Proposal or if an Acquisition Proposal is hereafter made or if any request for nonpublic information relating to Company or any of its Subsidiaries is made by any person or entity that has made an Acquisition Proposal or has advised such Shareholder that it may be considering making an Acquisition Proposal, such Shareholder shall within 24 hours notify Parent of the material details of such Acquisition Proposal or request (including the identity of the person or entity making such Acquisition Proposal, the terms thereof and the information requested thereby) and shall within 24 hours provide Parent with a copy of any Acquisition Proposal or request that is made in writing and copies of all correspondence relating thereto. Thereafter such Shareholder shall keep Parent fully apprised on a current basis of the status of any such Acquisition Proposal and of any modifications to the terms thereof. Each Shareholder hereby agrees to immediately cease and cause to be terminated all existing discussions or negotiations with any parties other than Parent conducted heretofore with respect to any Acquisition Proposal.

         1.6      Additional Documents.     Each Shareholder hereby covenants and agrees to execute and deliver any and all additional documents necessary or desirable, in the reasonable opinion of Parent, to carry out the purpose and intent of this Agreement.

ARTICLE II
REPRESENTATIONS AND WARRANTIES OF SHAREHOLDERS

        Each Shareholder hereby represents and warrants to Parent and Merger Sub as follows:

         2.1      Due Authorization, Etc.     Such Shareholder has all requisite power and authority and the legal capacity to execute, deliver and perform this Agreement, to appoint Parent as its proxy and to consummate the transactions contemplated hereby. The execution, delivery and performance of this Agreement, the appointment of Parent as such Shareholder's proxy and the consummation of the transactions contemplated hereby have been duly authorized by all necessary action on the part of such Shareholder. This Agreement has been duly executed and delivered by or on behalf of such Shareholder and constitutes a legal, valid and binding obligation of such Shareholder, enforceable against each Shareholder in accordance with its terms, except that such enforceability may be limited by bankruptcy, insolvency, moratorium or other similar laws affecting or relating to creditors' rights generally, and is subject to general principles of equity. There is no beneficiary or holder of a voting trust certificate or other interest of any trust of which such Shareholder is trustee whose consent is required for the execution and delivery of this Agreement or the consummation by such Shareholder of the transactions contemplated hereby.

         2.2      No Conflicts; Required Filings and Consents.     The execution and delivery of this Agreement by such Shareholder does not, and the performance of this Agreement by such Shareholder will not, (i) conflict with or violate any law applicable to such Shareholder or by which such Shareholder or any of such Shareholder's properties is bound or affected or (ii) result in any material breach of or constitute a material default (or an event that with notice or lapse of time or both would become a material default) under, or give to others any rights of termination, acceleration or cancellation of, or result in the creation of a lien or encumbrance on any assets of such Shareholder, including, without limitation, such Shareholder's Shares, pursuant to, any note, bond, mortgage, indenture, contract, agreement, lease, license, permit, franchise or other instrument or obligation to which such Shareholder is a party or by which such Shareholder or any of such Shareholder's assets is bound or affected.

        (b)   The execution and delivery of this Agreement by such Shareholder does not, and the performance of this Agreement by such Shareholder will not, require any consent, approval, authorization or permit of, or filing with or notification to, any governmental or regulatory authority (other than any necessary filing under the 1934 Act), domestic or foreign, except where the failure to obtain such consents, approvals, authorizations or permits, or to make such filings or notifications,

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would not prevent or delay the performance by such Shareholder of such Shareholder's obligations under this Agreement.

         2.3      Valid Title.     Such Shareholder is the sole, true, lawful and beneficial owner of such Shareholder's Shares with no restrictions on such Shareholder's voting rights or rights of disposition pertaining thereto. None of such Shareholder's Shares is subject to any voting trust or other agreement or arrangement with respect to the voting of such Shares. None of such Shareholder's Shares is subject to any adverse claims, options, liens, charge