Sonus Networks' Conference Call for Q4 Fy2000 and Year-End Financial Results

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WESTFORD, Mass., January 3, 2001 - Sonus Networks (Nasdaq: SONS) has scheduled a conference call for Thursday, January 18, 2001, at 4:30 pm EST to announce its Q4 FY2000 and year-end financial results.  Financial results are expected to be issued after the close of the market on Thursday, January 18, 2001.

Date: Thursday, January 18, 2001

Time: 4:30 pm EST

To listen via the Internet:
Sonus will host a live webcast of the conference call.  To access the webcast, visit www.sonusnet.com, Corporate, Investor Relations.

To listen via telephone:
Dial-in number: +1-312-470-0017
Passcode: SONUS

Replay:
A telephone playback of the call will be available following the conference, and ends at 11:59 pm EST on February 1, 2001.  The replay can be accessed by calling +1-402-220-9750.  The passcode for the replay is SONS (7667).

The webcast will be available on the Sonus Networks Investor Relations site through Thursday, February 1, 2001.  To access the replay of the webcast, visit www.sonusnet.com, Corporate, Investor Relations.

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 (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.