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Exhibit 23.1
CONSENT OF INDEPENDENT PUBLIC ACCOUNTANTS
As independent public accountants, we hereby consent to the incorporation by
reference in this registration statement on Form S-8 of our report dated
December 1, 2000 on the consolidated financial statements of telecom
technologies, inc. included in Sonus Networks, Inc.'s Prospectus filed
pursuant to Rule 424(b)(1) File No. 333-52682 dated January 12, 2000 and to
all references to our Firm included in this registration statement.
/s/ Arthur Andersen LLP
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Arthur Andersen LLP
Boston, Massachusetts
January 18, 2001
