1 EXHIBIT 23.1 CONSENT OF ERNST & YOUNG, LLP INDEPENDENT AUDITORS We consent to the incorporation by reference in this Annual Report (Form 10-K) of Juniper Networks, Inc. of our report dated January 15, 2001 included in the 2000 Annual Report to Stockholders of Juniper Networks, Inc. Our audits also included the financial statement schedule of Juniper Networks, Inc. listed in Item 14(a). This schedule is the responsibility of the Company's management. Our responsibility is to express an opinion based on our audits. In our opinion, the financial statement schedule referred to above, when considered in relation to the basic financial statements taken as a whole, presents fairly in all material respects the information set forth therein. We also consent to the incorporation by reference in the following registration statements of Juniper Networks, Inc. of our report dated January 15, 2001, with respect to the consolidated financial statements incorporated by reference and our report included in the preceding paragraph with respect to the financial statement schedule included in the Annual Report (Form 10-K) for the year ended December 31, 2000: Registration Form Statement Number Number Description - ------ ------ ----------- Form S-8 333-85387 Juniper Networks, Inc. Amended and Restated 1996 Stock Plan Juniper Networks, Inc. 1999 Employee Stock Purchase Plan Form S-8 333-32412 Juniper Networks, Inc. Amended and Restated 1996 Stock Plan Layer 5 1999 Stock Incentive Plan Form S-8 333-44148 Juniper Networks, Inc. 2000 Nonstatutory Stock Option Plan Form S-8 333-52258 Micro Magic 1995 Stock Option Plan Micro Magic 2000 Stock Option Plan Form S-3 333-44116 Equity Securities Form S-3 333-52260 Equity Securities /s/ Ernst & Young LLP Palo Alto, California March 23, 2001