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Standards-Based
Standards in the telecommunications industry have a long history. For many years, the EIA in the United States and the CCITT in Europe were the main bodies governing the establishment of standards. The goal of these committees was to establish the set of specifications that would define the ability of products and services to interoperate. Today these activities are generally governed by the International Telecommunications Union (ITU) and, as the name implies, the ITU provides international oversight on telecommunications technology developments and product offerings.
ATM has been adopted worldwide as the core network technology of the future, and currently all of the essential ATM standards are complete. After many years of careful evaluation of alternative technologies, the ITU–Telecommunications Standardization Sector (ITU–T) and other standards bodies agreed on ATM as viable for a long-term solution to any conceivable network-architecture or management-infrastructure compatibility, payload, and capacity demands. It can handle voice, data, video, and other multimedia streams using the same protocol and underlying hardware technology. ATM–technology development is heading towards terabit transport capacities in the near future, and it will not require software changes to accommodate it.
The benefit of the standards compliance is that investment in an ATM–based solution for communications protects the investment. Standards establish the baseline operations set for all compliant ATM products and services. As future requirements are recognized and defined, the ability of these functions to work with the established requirements is virtually guaranteed.
The ATM Forum recently released its VToA to the desktop specification. This specification addresses switched-voice services to a broadband ATM terminal in an open standards manner enabling multivendor implementations. It provides access to public and private network voice services and features for broadband terminals with connectivity to any telephone connected to these networks using G.711 PCM–encoded terminals.
Flexible Bandwidth Allocation and QoS Meet Customer Objectives
One of the major problems facing networks today is delivering customer traffic, whatever form it takes, with the expected and generally contracted quality of service (QoS). With ATM's flexible bandwidth allocation and flexible routing schemes, it is possible to accommodate any desired QoS for each network access, keeping the data flowing and the customers happy.
Support for Convergent Networks
ATM was designed to carry all types of traffic with interworking support for any network protocol or topology. By design, ATM supports mixed media (voice, data, and video), as well as interconnects with LANs, metropolitan-area networks (MANs), or WANs using traditional voice switching, packet technology (Internet protocol [IP]), frame technology, or SONET as the transport protocols. This comprehensive support provides the ideal platform for integration of any variety of services onto one platform.
Scalability
ATM scales in capacity, from the low end of T1 (1.5 Mbps) up to OC–48 (2.5 Gbps) or a range of speed support greater than 1,600 times from the low to the high end. ATM traffic-management techniques and use of VCs enables support for almost unlimited network size and topology. Today, ATM switches have capacities measured in the hundreds of Gigabits per second and, with the use of VCs, allows for the support of a network of almost unlimited size.
