Frame relay and SMDS services on a common ATM-based platform

Abstract

The evolution to broadband networking in the world market has started, enabled by the evolution of the transmission infrastructure and new switching techniques. The market is being driven by the high-speed requirements imposed by the unprecedented penetration of LAN technology and associated high-speed applications as well as the integration of voice, data, image and video requirements. The rapid deployment of more reliable, often fiber-based, facilities migrating to the Synchronous Digital Hierarchy (SDH) and the introduction of switching techniques such as Frame Relay and Asynchronous Transfer Mode (ATM) make possible the introduction of networking capabilities to satisfy emerging requirements. Frame Relay services rely on a stream-lined protocol implementation that makes advantage of end-to-end error control strategies to simplify network processing and enable higher throughput and lower delay. Frame Relay services are being targeted at the 64 Kbps to E1 range. The Asynchronous Transfer Mode (ATM) has been accepted as the transport mechanism for the future Broadband Integrated Services Digital Network (B-ISDN). Metropolitan Area Networks (MANs), based on IEEE 802.6 ATM principles, represent the first commercial application of ATM technology. An early MAN service is the Switched Multimegabit Data Service (SMDS) 1 which has been specified to provide efficient high-speed data transport in the E1 to 34 Mbps range with future extensions to incorporate isochronous transport for the addition of constant-bit rate services such as voice and video services. Similar to SMDS, Connectionless Broadband Networking Services (CBDS) are being defined by ETSI for the European Market with input from the European SMDS Interest Group (ESIG). This paper presents an ATM-based architectural approach, as implemented in At&T's Broadband Networking System 2000 (BNS-2000), to provide Frame Relay as well as SMDS services on the sam platform. The BNS-2000 represents a growable and modular architecture that has been built to comply with international standards such as ANSI, CCITT and ETSI to support the emerging needs of the market.