Exhibit 99.1

      Sonus Networks Appoints Controller and Principal Accounting Officer

    CHELMSFORD, Mass.--(BUSINESS WIRE)--Aug. 15, 2005--Sonus Networks
(Nasdaq: SONS), a leading supplier of service provider voice over IP
(VoIP) infrastructure solutions, today announced that Paul McDermott
has been appointed vice president of finance, corporate controller and
principal accounting officer. In this role, McDermott will direct the
Company's worldwide finance organization.
    "Paul brings to Sonus a broad range of experience having led the
financial operations of several technology companies," said Ellen
Richstone, chief financial officer, Sonus Networks. "He has the right
mix of finance and accounting experience to help drive the next phase
of Sonus' global growth. I look forward to Paul's contributions as we
all work toward extending Sonus' leadership position."
    McDermott has over 20 years of experience and a successful
background leading the finance operations of several high-technology
companies. Prior to joining Sonus, he was the chief financial officer
(CFO), treasurer and secretary at Network Intelligence Corporation, a
provider of appliance-based security event management products.
Previous to Network Intelligence Corporation, McDermott served as the
CFO of Firepond where he led the successful initial public offering of
the company. He has also held executive finance positions with
Serviceware Technologies, and Legent Corporation (acquired by Computer
Associates).
    "Sonus has established a preeminent position in the rapidly
growing VoIP market," commented McDermott. "I look forward to working
with the great team that Sonus has assembled, and contributing to the
Company's efforts to expand its global market leadership in such an
important and dynamic industry."

    About Sonus Networks

    Sonus Networks, Inc. is a leading provider of voice over IP (VoIP)
infrastructure solutions for wireline and wireless service providers.
With its comprehensive IP Multimedia Subsystem (IMS) solution, Sonus
addresses the full range of carrier applications, including
residential and business voice services, wireless voice and
multimedia, trunking and tandem switching, carrier interconnection and
enhanced services. Sonus' voice infrastructure solutions are deployed
in service provider networks worldwide. Founded in 1997, Sonus is
headquartered in Chelmsford, Massachusetts of U.S. Additional
information on Sonus is available at http://www.sonusnet.com.

    This release may contain forward-looking statements regarding
future events 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 the "Risk Factors" section of Sonus' Annual
Report on Form 10-K, dated March 15, 2005, and the "Cautionary
Statements" section of Sonus' Quarterly Report on Form 10-Q, dated
August 8, 2005, both filed with the SEC, which identify important risk
factors that could cause actual results to differ from those contained
in the forward-looking statements. Risk factors include among others:
the impact of material weaknesses in our disclosure controls and
procedures and our internal control over financial reporting on our
ability to report our financial results timely and accurately; the
unpredictability of our quarterly financial results; risks associated
with our international expansion and growth; consolidation in the
telecommunications industry; and potential costs resulting from
pending securities litigation against the company. Any forward-looking
statements represent Sonus' views only as of today and should not be
relied upon as representing Sonus' views as of any subsequent date.
While Sonus may elect to update forward-looking statements at some
point, Sonus specifically disclaims any obligation to do so.

    Sonus is a registered trademark of Sonus Networks. Open Services
Architecture is a trademark of Sonus Networks. All other company and
product names may be trademarks of the respective companies with which
they are associated.

    CONTACT: Sonus Networks, Inc.
             Investor Relations:
             Jocelyn Philbrook, 978-614-8672
             jphilbrook@sonusnet.com
             or
             Media Relations:
             Sarah McAuley, 212-699-1836
             smcauley@sonusnet.com