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Company Unveils New Suite of Software and Signaling Services; Announces Availability of Comprehensive ATM Offerings

WESTFORD, Mass., September 14, 1999 - Emerging industry leader Sonus Networks continues to deliver on its vision of migrating telephony to packet networks. The company today introduced a full range of media-independent, broadband solutions that will enable service providers to fully realize the promise of carrier-scale packet telephony, regardless of the underlying transport infrastructure. 

The innovative suite of solutions announced today include support for Voice over IP (VoIP) over ATM, voice telephony over ATM (VToA) and packet-over-SONET (POS), all of which can take advantage of high-speed, optical infrastructures. The company also announced the availability of new ATM modules for the award-winning GSX9000^TM Open Services Switch, including OC-3c and OC-12c SONET/SDH interfaces. 

With the expanded functionality announced today, service providers can enjoy the considerable benefits of packet telephony, regardless of the network transport technology. These benefits include: the rapid development and deployment of new value-added services; unparalleled scalability to handle massive call volumes; voice quality equal to or better than the PSTN; substantial operational savings; and more. Additionally, these solutions offer significant investment protection, as they leverage the GSX9000 platform. 

"We have always recognized that support for a full range of broadband infrastructures is a critical requirement for the service provider market, particularly with the larger, incumbent carriers," said Hassan Ahmed, president and CEO, Sonus Networks. "We've proven we can deliver carrier-class telephony in the IP world, and with the capabilities announced today, we're making broad-scale deployment of packet telephony a reality, regardless of the underlying transport." 

"Initially, we've seen the IP-centric "green field" carriers aggressively outlining their plans for packet telephony, but now that the incumbents are starting to evaluate this technology, requirements for broadband technologies, such as ATM, become more important," commented Chris Nicoll, director, Infrastructure Analysis, Current Analysis. "Clearly, Sonus has mapped its delivery of these new solutions to the development of the market for packet telephony in non-IP environments, and they're ready with the right product set, at the right time." 

Taking Voice to Optical Transport

Sonus is implementing a multi-pronged approach for delivering telephony in converged carrier public network environments. The company has been shipping Voice over IP (VoIP) using Fast Ethernet as the packet interface. With this announcement, Sonus is rolling out new VoIP over ATM capabilities, as well as support for voice telephony over ATM (VToA) and packet-over-SONET (POS). These new capabilities can take advantage of optical technologies such as DWDM, which is quickly gaining favor as the transport of choice for many service providers. 

With VoIP over ATM, voice traffic is encapsulated in IP, and ATM cells provide transport for delivery throughout the network. Using VToA, voice traffic is directly encapsulated into ATM cells for transmission of telephony over ATM. Both approaches capitalize on ATM's inherent quality of service (QoS) and leverage the transport provided in the significant ATM infrastructures built by many incumbent carriers. Packet-over-SONET eliminates the ATM layer completely as VoIP packets are transported directly in SONET frames for optical transport. 

As part of this announcement, Sonus announced the availability of new ATM modules for the GSX9000 Open Services Switch. These new offerings include a module with a single OC-12c interface and a module featuring four OC-3c interfaces. In addition to supporting VoIP over ATM and VToA, the new modules ensure carriers investment protection, as the same hardware can be leveraged to support POS, as the service provider's network evolves. 

Both the single OC-12c interface module and the four-port OC-3c interface module are scheduled for availability in Q4CY99. Pricing for these modules will be made available at a later date. 

About Sonus Networks

Sonus Networks, Inc. is delivering a new class of carrier solutions that enable the movement of telephony to converged packet networks and the development of a new generation of innovative voice and data services. The award-winning Sonus Packet Telephony suite and Open Services Architecture^TM (OSA) cut the time-to-market for competitive new service products from years to weeks, allowing carriers and third-party developers to sustain and 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, founded in 1997, is headquartered in Westford, Massachusetts and is privately held. Additional information is available at: http://www.sonusnet.com.

GSX9000 and Open Services Architecture are trademarks of Sonus Networks. All other company and product names may be trademarks of the respective companies with which they are associated