Exhibit 23.1 CONSENT OF KPMG LLP The Board of Directors Brocade Communications Systems, Inc. We hereby consent to the incorporation by reference into Brocade Communications Systems, Inc.'s previously filed Registration Statements on Form S-8 (Nos. 333-103571, 333-85187, 333-95653, 333-39126, 333-53734, 333-64260, 333-72480, and 333-100797) and Form S-3 (No. 333-84698) of our report dated November 14, 2003, except as to note 17, which is as of November 18, 2003, with respect to the consolidated balance sheets of Brocade Communications Systems, Inc. and subsidiaries as of October 25, 2003 and October 26, 2002, and the related consolidated statements of operations, stockholders' equity and comprehensive income (loss), and cash flows for each of the years in the two-year period ended October 25, 2003, and related financial statement schedule, which report appears in this annual report on Form 10-K of Brocade Communications Systems, Inc. for the year ended October 25, 2003. /s/ KPMG LLP Mountain View, California January 19, 2004