Clarent Corporation Shows NGN and Local Access Products at China Voice over IP Conference.

Business Editors/High Tech Writers

BEIJING--(BUSINESS WIRE)--May 16, 2000

Company Also Announces China Expansion

China VoIP Conference -- Clarent(TM) Corporation (NASDAQ: CLRN), a worldwide leader in providing carrier-grade, phone-to-phone Internet Protocol (IP) telephony solutions, announced today that it is showing two important new products at the China Voice over IP (VoIP) show in Beijing China - Clarent's next generation network (NGN) high density gateway product and Clarent's local access product. Clarent also announced significant company expansion in China.

Clarent's Expansion in China

Clarent is a supplier of IP telephony products to two of China's telecommunications service providers who have been granted licenses to operate IP telephony services - China Telecom and JiTong Communications.

To support Clarent's rapid growth in the China market, the company is opening two new offices. Effective May 16, 2000, Clarent has opened an office in Shanghai and effective May 23, 2000 Clarent will open an office in Guangzhou. In June 2000, Clarent plans to move its Beijing office to the Beijing COSCO building, which is a larger location.

Also, Clarent has established the Clarent China Research Institute(CCRI). Initially, the main responsibilities of CCRI are: 1) development and support of the China VoIP Standard compliance project; and 2) China localization of Clarent core technology.

Next Generation Network Product

The next generation network product being shown is a large scale, high density voice over IP gateway, designed to process high volumes of calls in a small footprint. The product is planned to support up to 1920 simultaneous calls on a single chassis and up to 7680 calls in a seven foot rack. The product also is intended as an element of Clarent's industry-leading IP telephony network architecture, and to be managed by the Clarent Command Center and its associated database.

The next generation network product is composed of a variety of components, including Clarent software and DSP and line interface technology from Audiocodes (AUDC) and Natural Microsystems (NASDAQ: NMSS). The next generation network product is designed to initially serve as a replacement to Class 4 or tandem central offices. Customer beta trials of this demonstrated next generation network product are planned to begin later this year.

Local Access Product

Clarent is also demonstrating phone calls through the new Customer Premise Equipment devices that Clarent announced were under development in January of this year. These calls will be made from a regular telephone, through the CPE device (which converts the voice to IP packets), through a DSL modem, through the Clarent Call Manager and then over the IP network, to terminate on a regular telephone on the other end of the call.

The CPE device being demonstrated is manufactured in Taipei and includes Clarent software as well as Texas Instruments/Telogy DSP and reference design technology. The Clarent Call Manager is a product under development that provides the call agent technology and end user features.

The CPE device and Clarent Call Manager products are planned to be replacements for traditional Class 5, or local, central offices and are also designed to interoperate in conjunction with the NGN platform for large scale networks. To demonstrate this, Clarent will also show several of the traditional Class 5 features through these new products, including Call Return, Speed Dial and Call Forwarding.

The CPE device and the Clarent Call Manager are also expected to begin beta trials later this year.

Both the NGN product and the local access product are planned components of the Clarent ONE (Clarent Open Network Environment) architecture - a series of open, scaleable IP telephony gateway and back end network operations and management products.

"We are extremely pleased to be demonstrating calls through these new products," said Jerry Chang, CEO and President, Clarent Corporation. "Clarent is making important progress toward developing new generations of products that will bring IP telephony from the core (inside) of the telecommunications network, where it is growing more prevalent today, to the local loop (outside) of the telecommunications network. We are looking forward to bringing these products to market and to increasing the adoption of this important new technology into the world's communications infrastructure." Jerry Chang plans to share more information about this demonstration and about the evolution of IP telephony from the inside of the network to the outside at his keynote address at the China VoIP conference at the Kerry Center Hotel in Beijing, P.R.C. on Wednesday, May 17, 2000.

Clarent's new office locations are:

Clarent Shanghai Office

21F, Block E1, Jiushi Renaissance Mansion

918, Huai Hai Zhong Rd.,

Shanghai, People's Republic of China

Tel: [phone]

Clarent Guangzhou Office:

Rm 3418, CITIC Plaza

233, Tian He North Rd.

Guangzhou, People's Republic of China

Tel: [phone]

Forward Looking Statements

This release may contain forward-looking statements regarding Clarent's products, business, customers or other factors that may affect future earnings or financial results. Such statements involve risks and uncertainties, including but not limited to potential issues relating to interoperability, inability to introduce new products, ability to retain key customers, changes in market conditions, government regulations, the international communications industry, technological changes and other factors, which could cause actual results to vary materially from those expressed in or indicated by the forward-looking statements. These risks and uncertainties are described further in the risk factors discussed in Clarent's Annual Report on Form 10-K, filed with the Securities and Exchange Commission on March 28, 2000.

About Clarent Corporation

Clarent Corporation is a premier provider of scalable, IP telephony products to carriers and Internet service providers around the world. Clarent's intelligent architecture and the Clarent Command Center enable Clarent products to route, manage, inter-connect and terminate high volumes of calls for service provider customers including the world's largest long distance telecommunication companies. According to an iLocus report published in 1999, more minutes travel across Clarent-enabled networks worldwide than those of any other equipment supplier.(1)

Founded in July 1996, Clarent is headquartered in Redwood City, California and has offices in major cities in Asia, Europe, Latin America and North America. Additional information about Clarent is available at www.clarent.com.

About Audiocodes

Founded in 1993, AudioCodes Ltd. (NASDAQ: AUDC) designs, develops and markets enabling technologies and communication system components for voice over packet networks. AudioCodes is a voice compression technology leader and the key originator of the ITU G.723.1 standard for the emerging IP Telephony market. AudioCodes' product line includes, VoIP communication boards, VoIP media gateway modules, voice over packet chip processors, media gateway subsystems and communications software. Our customers, the leading telecom and datacom OEM's such as: Alcatel S.A., Cisco Systems, Inc., Clarent Corporation, Lucent Technologies, Siemens and Vocaltec Communications are all featuring AudioCoded equipment. AudioCodes' international headquarters and R&D facilities are in Yehud, Israel with marketing and sales offices in San Jose, California. For more information on AudioCodes, please visit the company web site at http://www.audiocodes.com.

About Natural Microsystems

Natural MicroSystems (NASDAQ: NMSS), based in Framingham, MA, is the technology leader enabling the world's premier networking and communication equipment suppliers to create and accelerate New Network infrastructure and services. The company designs, develops and supplies network-quality hardware and software components and provides design and customization services.

NMS' products and technologies are deployed at the foundation of today's high-value communications systems, including network-based enhanced service platforms, wireless networks, media servers, unified messaging platforms, VoIP and other communications gateways, integrated voice and fax servers, and web-enabled call centers. By using Natural MicroSystems products and services, leading networking and communications suppliers are able to shorten time to market, leverage development resources, and offer truly global telecommunications solutions.

NMS' products and services are deployed in close to 50 countries. The company's quality processes have earned ISO 9002 certification. More information on the company is available at http://www.nmss.com.

Clarent is a registered trademark of Clarent Corporation in the United States and other jurisdictions. All other company or product names mentioned may be trademarks or registered trademarks of the respective companies with which they are associated.

(1)"IP Telephony Clearinghouses - A New Business Model". Published November 1999 by iLocus. iLocus, a division of Cape Saffron Ltd., is an UK-based research group focused on the IP telephony industry. http://www.ilocus.com

Natural MicroSystems and Natural Access are trademarks of Natural MicroSystems Corporation. Alliance Generation is a registered trademark of Natural MicroSystems Corporation. SpeechWorks, SpeechWorks Here, DialogModules and SpeechSite are trademarks or registered trademarks of SpeechWorks International, Inc. in the United States and other countries. All other company or product names mentioned may be trademarks or registered trademarks of their respective companies.