KDDI Selects Sonus Networks to Deploy Largest VoIP Network in Japan

KDDI Selects Sonus Networks to Deploy Largest VoIP Network in Japan

March 14, 2006

Leading Japanese Broadband Provider Plans to Build VoIP Network to Provide High Value-Added Telecommunications Services

    CHELMSFORD, Mass. and TOKYO, March 14
/Xinhua-PRNewswire/ -- Sonus Networks (Nasdaq: SONS), a
leading supplier of service provider voice over IP (VoIP)
infrastructure solutions, today announced that KDDI, a
leading telecommunication service provider in Japan,
selected Sonus Networks as the exclusive vendor for their
convergence-enabled packet voice network.

    In the first phase of this multi-million dollar
contract, KDDI is deploying Sonus' industry-leading
architecture, including the GSX9000(TM) Open Services
Switch, the PSX(TM) Call Routing Server and the Sonus
Insight(TM) Element Management System.  The new packet
voice network will deliver enhanced voice services to one
of the most technologically advanced societies in the world
and is planned to be the largest IP telephony network in
Japan. 

    "By 2008, KDDI plans to have 100 percent of its
long-distance traffic on a Sonus-based VoIP network,"
said Yukio Takahashi, General Manager, IP Network
Engineering Division, Corporate Technology Sector, KDDI
Corporation.  "Sonus has demonstrated a clear
commitment to the Japanese market, with a proven record of
delivering superior products and customer support.  With
this implementation, we will realize substantial
operational savings and have the flexibility to expand our
IP-based network to offer feature-rich next generation
services, thereby delivering enhanced customer loyalty and
satisfaction."

    In the first phase of this deployment, KDDI is
deploying Sonus' solution to deliver long distance
functionality for their consumer voice service plans --
Metal Plus, MYLINE and Hikari Plus.  In future phases of
the deployment, KDDI will expand its ubiquitous network to
deliver triple-play services to customers nationwide.

    "KDDI's deployment represents a major milestone in
the evolution of the market and reaffirms their leadership
position in the broadband communications industry,"
said Hassan Ahmed, chairman and CEO, Sonus Networks. 
"KDDI has taken a very aggressive approach because
they recognize both the immediate and longer term benefits
to their business and their customers.  We are very proud
that KDDI has selected Sonus as the foundation for their
new VoIP network." 

    "Sonus Networks is uniquely positioned to
effectively enable KDDI's transition to a VoIP network
because of our experience in the Japanese market and the
proven scalability and reliability of our solutions in both
wireline and wireless networks.  By deploying a packet voice
network from Sonus, KDDI can be confident that they will
continue to deliver the same high levels of service that
their customers have come to expect.  Additionally, the
Sonus solution enables KDDI to rapidly expand their network
into new segments of the market and to deliver new
services," said Takayuki Oshima, Managing Director of
Japan, Sonus Networks.  
    
    About KDDI 

    KDDI Corporation ( http://www.kddi.com/english ) is the
only single company in Japan that can provide full-service
telecommunications and answer all customer needs from
fixed-line to mobile telecommunications as well as
comprehensive Internet services.  Taking full advantage of
the integrated strengths, the company realizes the
convergence of Mobile and the Internet to create a highly
advanced telecommunications environment and provide
customers with unsurpassed service.  KDDI restarted with
the merger of DDI, KDD and IDO on October 1, 2000 to
combine the cumulative business resources of three
companies that include not only extensive achievements in
the fields of domestic, international and mobile
communications, but also world-renowned R&D
capabilities and a cutting-edge infrastructure realized by
an optical-fiber network.

    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.  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 November 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, Inc.
 All other company and product names may be trademarks of
the respective companies with which they are associated.

    For more information, please contact:  

    Media Relations (Asia):				
     Chew Peng Healey					
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     Email: [e-mail]				 

    Media Relations (US):
     Sarah McAuley	
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     Jocelyn Philbrook
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     Email: [e-mail]

    Media Relations (EMEA):
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SOURCE  Sonus Networks