Exhibit 23.1

Consent of Ernst & Young LLP, Independent Registered Public Accounting Firm

We consent to the incorporation by reference in the Registration Statement (Form S-8 No. 333-137502) pertaining to the 2006 Equity Incentive Plan, 2006 Director Option Plan, and the 2006 Employee Stock Purchase Plan of Riverbed Technology, Inc., of our report dated February 8, 2007, with respect to the consolidated financial statements and schedule of Riverbed Technology, Inc. included in this Annual Report (Form 10-K) for the year ended December 31, 2006.

/s/ ERNST & YOUNG LLP

San Francisco, California

February 8, 2007