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Exhibit 23.1
CONSENT OF ERNST & YOUNG LLP, INDEPENDENT AUDITORS
We consent to the incorporation by reference in the Registration Statement
(Form S-8) pertaining to the 1999 Non-Employee Director's Stock Option Plan and
1999 Amended and Restated Equity Incentive Plan of Clarent Corporation of our
report dated January 19, 2000, with respect to the consolidated financial
statements and schedule of Clarent Corporation included in its Annual Report
(Form 10-K) for the year ended December 31, 1999, filed with the Securities
and Exchange Commission.
/s/ Ernst & Young LLP
Palo Alto, California
August 1, 2000
