Excel Switching Announces the EXS Media Gateway.

LAS VEGAS--(BUSINESS WIRE)--April 14, 1999--

Unprecedented Scalability, Flexibility and Reliability for

Voice over IP (VoIP) Telephony Gateway Applications Worldwide

Excel Switching Corporation (NASDAQ:XLSW), a leading provider of open platforms for telecom networks worldwide, today announced the EXS Media Gateway, at Voice on the Net '99 (Booth # 605). The EXS Media Gateway is a carrier-class IP telephony media gateway, supporting up to 3,840 VoIP ports in a single cabinet. Multiple cabinets can be interconnected to form a 14,400 port Media Gateway System. EXS Media Gateway's unique architecture supports the functionality of both a multi-protocol VoIP media gateway and a versatile signaling gateway, either as separate network elements or combined in a single platform.

EXS Media Gateway will enable Next Generation Telcos worldwide to address "real world" requirements with powerful, highly available and scalable communications for IP Telephony applications on an open standards-based platform. EXS Media Gateway is an open programmable IP Telephony gateway that provides transparent bridging between legacy Public Switched Telephone Network (PSTN) Intelligent Network (IN) elements and New World IP-centric carrier services.

"Excel's IP Telephony architecture allows Priority Call Management to quickly develop unique solutions that directly address carrier needs for integrated IN/IP enhanced service platforms and standalone SS7 signaling gateways," said Lois Andreasen, vice president of marketing of Priority Call Management, based in Wilmington, MA. "By leveraging Excel's vast signaling experience, Priority Call Management can deliver complete solutions for Next Gen Telcos."

EXS Media Gateway provides service differentiation, adaptability and comprehensive protocol support with Excel's patented, open Programmable Protocol Language (PPL), at the signaling, call control, and services layers. The call control and service layer flexibility offered by Excel's PPL technology allows EXS Media Gateway to evolve with the emerging media gateway control standards such as MGCP, SGCP, IPDC and H.323 and allows customers to quickly adapt to emerging variants of IP Telephony protocols and call control models. Similarly, the PPL enabled signaling layers of the EXS Media Gateway platform reduces carriers' time-to-market for worldwide IP deployment.

"Next Generation Telcos have recognized the advantages of open platforms and general purpose computer technologies and EXS Media Gateway uniquely addresses the concept of an open programmable IP telephony gateway," said Robert Madonna, president and CEO of Excel. "EXS Media Gateway leverages Excel's leadership technology and experience in open programmable systems and infrastructure solutions to meet the demands of the rapidly evolving Next Gen Telcos."

EXS Media Gateway is a compact, carrier-grade platform that supports 960 VoIP channels in a single 19", NEBS-III compliant rack-mountable shelf. 4 EXS Media Gateway shelves can easily be stacked in a single 7-foot cabinet for a total of 3,840 VoIP ports. Additionally, these shelves can be interconnected via Excel's fault-tolerant 1.2Gbps EXNET technology to create a non-blocking 14,400 port Media Gateway system. A new IP packet engine card, the Voice Data Access Concentrator (VDAC), enables the VoIP packet technology in the EXS Media Gateway platform. With high performance Digital Signal Processing (DSP) and multi-processor design, VDAC can simultaneously support 160 VoIP channels with a wide array of vocoder options in a single shelf slot.

Both EXS Media Gateway and the VDAC module will be on display at Excel's booth #605 at the Voice on the Net show in Las Vegas April 12 -16.

About ONE Architecture

ONE Architecture defines Excel's strategic technology framework for its state-of-the-art Expandable Switching System (EXS). It enables carriers and developers to integrate network routing, enhanced services, IP Telephony and media support on a single, highly scalable platform. With its product and services, Excel provides a scalable network solution regardless of legacy signaling or emerging IP signaling protocols, switching capacity, or billing and subscriber services offered from the PSTN or IP network.

About Excel Switching Corporation

Excel Switching Corporation is a leading provider of open switching platforms for telecommunications networks worldwide. Excel develops, manufactures, markets and supports a family of open, programmable, carrier-class switches and gateways that address the complex enhanced services and wireless and wireline infrastructure needs of network providers. Excel's products are currently deployed in telecommunications networks worldwide. Visit Excel's website at http://www.xl.com.

This release may contain statements which are "forward looking," and is subject to risks and uncertainties that could cause actual results to differ significantly from expectations. Factors that might cause such a difference include, but are not limited to, those relating to Excel's highly competitive market; dependence on and concentration of relationships with application developers, original equipment manufacturers and systems integrators; evolving market for telecommunications services and rapid technological change; possible delayed or lengthy sales cycles; risks associated with concentrated product family and new product introductions; Excel's dependence on its proprietary rights; and other risks identified in the Company's Securities and Exchange Commission filings including those risks identified in the section entitled "Risk Factors" of the Company's Annual Report for the year ended December 31, 1998 on Form 10-K. Product and service names used within are trademarks, registered trademarks and service marks of their respective owners.