McDATA CORPORATION CONSULTING AND NON-COMPETITION AGREEMENT

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Exhibit 99.3

McDATA CORPORATION
CONSULTING AND NON-COMPETITION AGREEMENT

        THIS CONSULTING AND NON-COMPETITION AGREEMENT (the " Agreement ") is entered into subject to and effective as of June 1, 2005 (the " Effective Time ") by and between McDATA CORPORATION , a Delaware corporation (the " Company "), and THOMAS G. HUDSON (" Consultant ").

Recitals

        WHEREAS Consultant has been the President and CEO of Computer Network Technology Corporation, a Minnesota corporation ("CNT"); and

        WHEREAS, this Agreement is entered into in connection with that certain Agreement and Plan of Merger, dated as of January 17, 2005, as amended (the " Merger Agreement "), by and among the Company, Condor Acquisition, Inc., a Minnesota corporation and wholly-owned subsidiary of the Company (" Sub "), and CNT, pursuant to which the Company is to acquire CNT through a statutory merger in which Sub is to merge into CNT, with CNT surviving as a wholly-owned subsidiary of the Company (the " Merger "); and

        WHEREAS, Consultant has gained certain valuable knowledge and expertise in connection with CNT's strategy, products, services, organization, customers, partners and other proprietary matters related to CNT's business; and

        WHEREAS, the parties hereto believe that the non-competition provisions set forth in Section 8 of this Agreement are reasonably necessary to preserve the value of the business being acquired by the Company as a result of the Merger; and

        WHEREAS, the parties hereto wish to enter into this Agreement to set forth the terms and conditions of Consultant's future obligations to the Company, including Consultant's non-compete obligations set forth in Section 8 of this Agreement, for which Consultant will receive consideration as more fully set forth on Exhibit B attached hereto;

        NOW, THEREFORE, in consideration of good and valuable consideration, the receipt and adequacy of which is hereby acknowledged, the parties hereto hereby agrees as follows:

Agreement

        1.      Consulting Relationship . During the term of this Agreement, Consultant will provide on demand consulting services (the " Services ") to the Company as described, and on the terms set forth, on Exhibit A attached to this Agreement. Consultant shall use commercially reasonable efforts to perform the Services in a manner reasonably satisfactory to the Company.

        2.      Consideration . As consideration for the Services to be provided by Consultant, the Company shall pay to Consultant the consideration specified on Exhibit B attached to this Agreement. Such consideration shall be paid to Consultant during his lifetime, and to his spouse, if she survives him, after his death, or if there is no surviving spouse, to his estate.

        3.      Support . The Company will provide Consultant with such support facilities and space as may be required in the Company's reasonable judgment to enable Consultant to perform the Services properly.

        4.      Expenses . Consistent with the Company's policies, the Company shall reimburse Consultant for out-of-pocket expenses reasonably incurred by Consultant in the performance of the Services requested by the Company hereunder.

        5.      Term and Termination . Consultant shall serve as a consultant to the Company for a period commencing on the day immediately after the closing of the Merger (the " Closing Date ") and will continue to provide the Services as requested by the Company pursuant to the terms hereof for up to twelve (12) months thereafter. This Agreement is not terminable for any reason, including the death of Consultant. The parties hereto may extend the term of the Agreement upon the written consent of both parties. Notwithstanding any other provision set forth herein to the contrary, any such termination of this Agreement shall not affect the non-competition obligation of Consultant set forth in Section 8 below.

        6.      Independent Contractor . Consultant's relationship with the Company will be that of an independent contractor and not that of an employee. Consultant will not be eligible for any employee benefits, nor will the Company make deductions from payments made to Consultant for taxes, all of which will be Consultant's responsibility. Consultant will have no authority to enter into contracts that bind the Company or create obligations on the part of the Company, without the prior written authorization of the Company.

        7.      Supervision of Consultant's Services . All Services to be performed by Consultant will be at the direction of the Company's CEO and Chairman. Consultant may be reasonably required to prepare written reports as to the progress of various Services.

        8.      Covenant Not to Compete . In consideration of the Company entering into this Agreement with Consultant, Consultant agrees that during the "Restricted Period" (as hereinafter defined), Consultant shall not, directly or indirectly, provide services to any "Competing Business" (as hereinafter defined), in any manner or capacity (e.g., as an advisor, investor, member, principal, agent, partner, officer, director, shareholder, employee, member of any association or