General DataComm Announces New Multiservice Access Concentrators --MAC-- for GDC APEX Family.

LAS VEGAS--(BUSINESS WIRE)--May 5, 1998--NetWorld+Interop98 Booth No. 3917 South Hall

General DataComm, Inc. (NYSE:GDC) today announced that it has added several new members to its industry leading, award winning GDC APEX(R) family of broadband networking systems -- the MAC-100, MAC-200 and MAC-300. These new Multiservice Access Concentrators provide end users with lower cost access to high speed digital networks and integrate seamlessly within the existing APEX product line. In conjunction with the new AT-1000 ANTU (See separate release: GDC Announces New AT-1000 ATM Network Terminating Unit for its Broadband Networking Product Family), these new devices extend the reach of the GDC broadband networking family to the remote branch office where lower cost access into public or private ATM/Frame Relay networks is key.

The MAC-100 is a low speed ATM access concentrator which offers Ethernet LAN extension and frame relay service interfaces simultaneously. The ATM network interface is fully ATM Forum UNI 3.1 compliant and provides both PVC and SVC services at either T1 or E1 speeds. An optional LAN emulation client software addition enables the MAC-100 to participate in ATM Forum-based LAN emulation environments over the ATM wide area network. The MAC-100 is suitable for applications such as Internet access and wideband multiservice access to private or public ATM networks, and interfaces with a T1 or E1 ATM port on the APEX switching system.

The MAC-200 and MAC-300 are multiservice access devices designed to consolidate LAN, IP, voice, frame relay and other protocols from branch offices into a frame relay backbone. The MAC-200 is a data FRAD offering multiple Ethernet and serial interfaces and supporting Layer 3 IP and IPX routing, SNA/LLC2 and frame relay protocols. The MAC-300 is a highly featured voice and data FRAD offering all of the capabilities of the MAC-200 plus the ability to take in and compress up to four analog or digital voice channels for transmission over the frame relay network at rates as low as 6.3 Kbps. Additionally, these products include an internal firewall feature designed to allow users to partition sensitive LAN traffic away from areas where general access may be required, such as to a Web site host.

Both the MAC-200 and MAC-300 are fully compatible with the frame relay services provided by the APEX switch or by other frame relay network providers. In particular, they incorporate mechanisms designed to ensure that voice over frame relay traffic receives the appropriate higher level of prioritization through the network. The MAC-200 and MAC-300 both support the relevant frame relay standards and specifications from the ITU-T, ANSI and the Frame Relay Forum.

Uniquely, the MAC-300 will also operate as an ATM access concentrator through a software-only upgrade planned for the second half of 1998. This enables users to invest in an initial frame relay network deployment with the assurance of investment protection through a simple migration path to a full ATM system. All of the same MAC-300 service features such as IP, frame relay and voice will be supported in the ATM environment.

The MAC-100, MAC-200 and MAC-300 are designed to be used both within North America and internationally, and may be optioned with either T1 or E1 line interfaces for connection to the network. The T1 versions incorporate a full T1 CSU/DSU feature, removing the need for a costly additional external CSU/DSU at each site.

All of the new Multiservice Access Concentrators will be fully managed under GDC's new ProSphere(TM) Network Management System, alongside its other networking products such as its GDC APEX(R) switching system. Each of the products may be managed using either an external craft port or through an in-band SNMP interface.

Charles P. Johnson, chairman and chief executive officer of General DataComm, said, "The new MAC family provides cost-effective, integrated access to frame relay and backbone ATM networks, allowing users to easily extend their GDC broadband networks to smaller branch office sites. The rich feature sets offered in the MAC series make them ideal for cost-effective multiservice access to our GDC APEX(R) networking systems. Through integration within GDC's ProSphere(TM), the network operator is assured of full end-to-end network management for maximum configuration, control and troubleshooting for the complete system.

The MAC family of access concentrators will be available in May, 1998, and start at a list price of $1,645.

About General DataComm

GDC (http://www.gdc.com) is an acknowledged global leader in the design, development, and manufacture of multiservice communications systems for service providers and enterprise businesses. Its innovative COLOSSAS(TM) architecture includes the flagship STROBOS(TM) and GDC APEX(R) multiservice switching platforms, used extensively within the world's largest public ATM Wide Area Networks, and a broad range of Advanced Network Access products to provide integrated E1, T1, IDSL access to public and private networks, all managed under a distributed, open network management framework, ProSphere(TM). GDC is headquartered in Connecticut, USA, and has an extensive network of subsidiaries and partners located throughout North America, South America, Europe, the Middle East, Asia, and the Pacific Rim.

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GDC APEX, COLOSSAS, STROBOS, and PROSPHERE are trademarks or registered trademarks of General DataComm, Inc. All other companies and/or products mentioned in this document are the property of their respective trademark holders.

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