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                       SECURITIES AND EXCHANGE COMMISSION

                             WASHINGTON, D.C. 20549


                                    FORM 8-K

                                 CURRENT REPORT

                     Pursuant to Section 13 or 15(d) of the
                         Securities Exchange Act of 1934

       Date of report (Date of earliest event reported): October 13, 2000

                              SONUS NETWORKS, INC.
             (Exact name of registrant as specified in its charter)

   Delaware                         000-30229                  04-3387074
--------------               ------------------------       -------------------
  (State of                  (Commission File Number)         (IRS Employer
Incorporation)                                              Identification No.)

                       5 Carlisle Road, Westford, MA 01886
               ---------------------------------------------------
               (Address of principal executive offices) (Zip Code)

                                 (978) 692-8999
              ----------------------------------------------------
              (Registrant's telephone number, including area code)

                                       N/A
          -------------------------------------------------------------
          (Former name or former address, if changed since last report)

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ITEM 5.  OTHER EVENTS.

         Sonus Networks, Inc. (the "Company") effected a three-for-one stock
split of its common stock, $0.001 par value per share ("Common Stock") in the
form of a stock dividend paid on October 6, 2000 to those holders of record of
the Company's Common Stock at the close of business on September 29, 2000.

         A copy of the press release issued by the Company announcing the
three-for-one stock split is attached hereto as Exhibit 99.1 and is incorporated
herein by reference.


ITEM 7.  EXHIBITS.

EXHIBIT
NUMBER       DESCRIPTION
-------      -----------

 99.1        Press Release dated August 15, 2000 issued by Sonus Networks, Inc.


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SIGNATURES

         Pursuant to the requirements of the Securities Exchange Act of 1934,
the registrant has duly caused this report to be signed on its behalf by the
undersigned hereunto duly authorized.

Date:    October 13, 2000

                     SONUS NETWORKS, INC.

                     By: 
                         --------------------------------------
                     Stephen J. Nill, Chief Financial Officer,
                     Vice President of Finance and Administration
                     and Treasurer (authorized officer and principal
                     financial and accounting officer)



                               EXHIBIT INDEX

EXHIBIT
NUMBER       DESCRIPTION
-------      -----------
 99.1        Press Release dated August 15, 2000 issued by Sonus Networks, Inc.






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                                                                 EXHIBIT 99.1

                  SONUS NETWORKS ANNOUNCES 3-FOR-1 STOCK SPLIT

WESTFORD, MASS., AUGUST 15, 2000 - Sonus Networks (Nasdaq: SONS), a leading
provider of voice infrastructure solutions for the new public network, today
announced that the Company's board of directors has approved a three-for-one
stock split of the Company's common stock. The stock split will be effected in
the form of a stock dividend and stockholders of record at the close of business
on September 29, 2000 will be entitled to two additional shares of common stock
for each outstanding share of common stock held on that date. The additional
shares are expected to be distributed by the Company's transfer agent on or
about October 6, 2000 and the Company expects that its common stock will begin
trading on a split-adjusted basis on October 9, 2000.

ABOUT SONUS NETWORKS

Sonus Networks, Inc. is a leading provider of voice infrastructure products for
the new public network. Sonus' solutions enable service providers to deploy an
integrated network capable of carrying both voice and data traffic, and to
deliver a range of innovative, new services. The Sonus Open Services
Architecture(TM) (OSA) and award-winning Packet Telephony suite cut the
time-to-market for competitive
 new service products, allowing carriers and
third-party developers to expand marketshare and build important new revenue
streams. Its highly scalable products fully interoperate with and extend the
life and utility of today's public network. Sonus embodies in its management and
staff decades of experience in developing carrier-class voice, data and
multimedia solutions for implementation in the world's largest networks. Sonus,
founded in 1997, is headquartered in Westford, Massachusetts. Additional
information on Sonus is available at http://www.sonusnet.com.

This release may contain projections or other forward-looking statements
regarding future events or the future financial performance of Sonus that
involve risks and uncertainties. Readers are cautioned that these
forward-looking statements are only predictions and may differ materially from
actual future events or results. Readers are referred to Sonus' Quarterly Report
on Form 10-Q for the quarter ended June 30, 2000, filed with the SEC, which
identifies important risk factors that could cause actual results to differ from
those contained in the forward-looking statements. These risk factors include,
among others, the Company's ability to grow its customer base, dependence on new
product offerings, market acceptance of our products, rapid technological and
market change and manufacturing and sourcing risks.

For more information, please contact:

Beth Morrissey
Sonus Networks
978-589-8579
bmorrissey@sonusnet.com

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