Castle Networks Partners with Industry's Top OSS/BSS Solution Providers.

CHELMSFORD, Mass.--(BUSINESS WIRE)--June 8, 1999--

CastleSentry Alliance Program brings state-of-the-art control

and functionality to both voice and data services

Castle Networks, the leading developer of next-generation central-office-based communications technologies and a Unisphere Solutions company, announced today the CastleSentry Alliance Program, a teaming initiative to offer end-to-end network management, operation support system (OSS), and business support system (BSS) solutions to its telecommunications service provider customers. Under the CastleSentry Alliance Program, a number of leading OSS and BSS solution providers will integrate their products with Castle's C2100 Services Mediation Platform (SMP) and its CastleSentry Element Management System (EMS), which was announced separately today. The companies will also conduct joint marketing, sales, and product development activities in order to integrate voice and data capabilities from the perspective of services, signaling and management.

"Today's service providers face unprecedented complexity in managing multiple network infrastructures, many logically isolated by function or physically isolated by geography," said Steve Kelly, executive vice president at Castle Networks. "Our CastleSentry EMS strategy is aimed at easing our carrier customers' existing network management challenges and offering broad, enterprise-wide solutions. The CastleSentry Alliance Program helps us do this quickly and effectively, while devoting our internal resources to ongoing development of the C2100 SMP."

At the launch of this program, Castle Networks announces today alliances with four leading vendors of OSS and BSS solutions: CommTech Corporation, Daleen Technologies, Inc., Micromuse, Inc. and XACCT Technologies. Additional alliances will be announced in the near future.

CommTech Corporation is a leading developer of provisioning systems for Lucent 5ESS, Nortel DMS and Siemens EWSD central office switches, and includes among its customers AT&T, SNET, BellSouth, Brooks/Worldcom, GTE, TDS Metrocom, Bell Atlantic, NBTel, Southwestern Bell, TCG and US West. The combination of CommTech's strong provisioning capabilities and CastleSentry's open, Java-based management capabilities bring customers a single provisioning interface for their legacy Class 5 systems and the Castle Networks C2100 Services Mediation Platform, a next generation voice switching and application platform -- an unprecedented capability.

When asked about the Castle Networks alliance, Frank Lauria as Vice President of Strategic Business Development with COMMTECH Corporation commented "We are pleased to play an active role with Castle Networks, and with Unisphere Solutions by providing complementary provisioning, work process, order management, and OSS products. Since our OSS products are deployed in most of the major domestic service providers we can play an important role in the implementation of Castle's next generation switching technology. Similarly, this alliance strengthens our strategy of managing voice and data services together using the COMMTECH FastFlow OSS portfolio."

Daleen Technologies, Inc. designs, develops and implements convergent billing and customer care software solutions for the telecommunications industry on a worldwide basis. The company distributes its flagship product, BillPlex(tm) through Cap Gemini, Danet, Integris-Groupe Bull, Kanbay, Unisys and other systems' integrators. In addition to its Boca Raton, FL headquarters, the company has regional offices throughout the United States. Daleen brings to carrier customers leading edge billing and customer care platforms, and enhances Castle Networks' ability to provide solutions across the carrier enterprise and upward through service management and business management layers.

"As a leader in the convergent billing and customer industry, Daleen continues to strengthen its competitive advantage by integrating with world class solutions like those of Castle Networks." said David Corey, president and COO of Daleen Technologies. "Through its Enterprise Application Framework, Daleen offers a plug-and-play approach to integration. This simplified integration and the complementary alignment between Daleen's flagship product, BillPlex and Castle Network's products will enable service providers to offer the most competitive integrated voice and data services."

Micromuse Inc. is a leading provider of service-level management software. The company's Netcool suite is used by managed network service providers, Internet service providers, telecommunications firms, and corporations worldwide. Customers include AirTouch, America Online, AT&T Wireless, BT, Cable & Wireless, Cellular One, Deutsche Telekom, GEIS, ICG Communications, ITC DeltaCom, the MCI WorldCom Companies, MindSpring Enterprises, U S WEST !NTERPRISE, and a number of financial investment firms. The companies will integrate Micromuse's Netcool products with Castle Networks' CastleSentry EMS -- as well as other Unisphere platforms -- to provide their customers with event correlation, integrated fault management, and support for service level agreements and quality of service guarantees across the carrier enterprise.

"Micromuse and Castle Networks both recognize the pressure our customers face in bringing new services to market with lightning speed," said Greg Brown, chairman and CEO of Micromuse, Inc. "We are delighted about joining Castle Network's Alliance Program and are confident that Castle Networks' growing customer base will benefit greatly from the industry-leading, multivendor fault and service-level management technology we offer through our Netcool application suite."

XACCT Technologies is a leader in the emerging IP mediation market; its award-winning intelligent software solutions enable service providers and enterprises to accurately account and bill for metered services and applications. XACCTusage will provide a single point of interface between the C2100 and several customer care and billing (CCB) systems. XACCT's product also allows the C2100 to integrate into legacy billing environments, such as AMA/BAF.

"We are pleased to partner with Castle and support the C2100 SMP. It complements our product and our business strategy," said Anil Uberoi, vice president of marketing at XACCT. "The combined solution offers a very attractive option for service providers, enabling them to deploy new differentiated services with minimal disruption to their existing CCB infrastructures."

The CastleSentry Alliance Program complements the CastleSentry EMS by offering service providers best-of-breed solutions at the multi-element network, service, and business layers of the TMN hierarchy, while offering support for legacy interfaces and established network management practices from both the voice and data worlds.

Designed to accommodate a variety of user interfaces and management skill sets, CastleSentry EMS provides equal functionality and value whether deployed in a traditional data environment (such as an Internet Service Provider or Data Competitive Local Exchange Carrier) or a traditional voice network (such as a Regional Bell Operating Company). Because approaches to such routine tasks as service provisioning and fault management have evolved separately in the data and voice arenas, expertise applicable to one sector rarely applies to the other. As a result, carriers have tended to dedicate technical staff entirely to specific network segments, or even to specific network elements.

By bringing together a team of experts in a variety of critical solution areas, carriers have the required resources to simplify the Herculean task of integrating new capabilities into, and operating, their complex, dynamic networks. Castle Networks and its partners offload the burden of integration and operations, and their associated costs, from service providers. This frees up critical financial/human resources for development of innovative new services that will ultimately allow carriers to differentiate and win market share.

The CastleSentry Alliance Program will augment network management, OSS and BSS solutions under active development at Unisphere Solutions. These solutions will bring together the products of Castle Networks, Argon Networks, Redstone Communications and Accelerated Networks under a single management and operation support umbrella.

About Castle Networks

Castle Networks, a Unisphere Solutions company, designs next-generation central office-based communications platforms that address the cost-effective convergence of circuit switched voice networks and packet switched data networks. The company brings together voice and data expertise with top talent from telecommunications and networking companies including: Bay Networks/Nortel Networks, Cabletron Systems, Cascade Communications/Ascend Communications, Cisco Systems, Digital Equipment/Compaq Computer, Lucent Technologies and Telco Systems. Focused on delivering carrier class voice and data convergence equipment for 21st Century telecommunications networks, Castle Networks' mission is to transform telecommunications by migrating the PSTN to a high-performance, low-cost, multi-service network irrespective of where the user gains access. For more information, visit our web site at www.castlenetworks.com.

About Unisphere Solutions, Inc.

Unisphere Solutions, Inc., based in Burlington, Mass., designs, markets and services converged networking solutions to Service Provider and Enterprise customers. Founded in March 1999 by Siemens, the company brings together the know-how of over 500 people, concentrating assets from both Siemens Information and Communication Networks Group and several technology companies it has acquired in the United States to deliver end-to-end networking solutions for converged networks. The Company leverages its relationship as a wholly owned subsidiary of Siemens to gain access to a channel of Siemens Information and Communication Networks' 26,000 sales and support people worldwide. Further information on Unisphere Solutions can be found on the Internet at www.unispheresolutions.com.

Castle Networks, Unisphere Solutions and CastleSentry are trademarks of Unisphere Solutions, Inc. All other brand and product names are registered trademarks or trademarks of their respective holders.