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EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

        We consent to the incorporation by reference in Registration Statement Nos. 333-61940 and 333-66982 on Form S-3 and Registration Statement Nos. 333-43334, 333-53970, 333-54932, 333-105215, 333-124777 and 333-150022 on Form S-8 of our reports dated February 25, 2009, relating to the consolidated financial statements of Sonus Networks, Inc. (which report expresses an unqualified opinion and includes an explanatory paragraph relating to the adoption of Financial Accounting Standards Board (FASB) Interpretation No. 48, Accounting for Uncertainty in Income Taxes, an interpretation of FASB Statement No. 109, effective January 1, 2007), and the effectiveness of Sonus Networks, Inc.'s internal control over financial reporting, appearing in this Annual Report on Form 10-K of Sonus Networks, Inc. for the year ended December 31, 2008.

/s/ DELOITTE & TOUCHE LLP

Boston, Massachusetts
February 25, 2009

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EXHIBIT 23.1

CONSENT OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM