PairGain, ADC, Level One Join Forces to Develop Enhanced Single Pair HDSL Standard
'HDSL2' Modulation, Line Code Scheme to Provide Full HDSL Performance Over Single Copper Pair
June 23, 1997 06:00 AM
SACRAMENTO, Calif., June 23 /PRNewswire/ -- PairGain Technologies Inc. [Nasdaq: PAIR], ADC Telecommunications, Inc. ADCT , and Level One Communications Incorporated LEVL , three world leaders in advanced telecommunications technologies, today announced that they will collaborate to develop a new standard for second generation High-bit-rate Digital Subscriber Line technology, known as HDSL2.
The three companies are developing a powerful HDSL2 standard proposal that will let service providers deliver fall T1 (1.544 Mbps) performance over a single twisted pair cable, with the same reach, robustness and spectral compatibility of today's two-pair HDSL. This will permit local exchange carriers (LECs) and telecom service providers to meet rapidly increasing demands for business and Internet access services.
The three companies are collaborating on the HDSL2 standard development with Level One and PairGain planning to jointly develop silicon solutions. ADC and PairGain will develop systems based on the enhanced technology; Level One will offer silicon solutions that implement the new standard. By working together, the companies believe that their combined expertise and market presence can accelerate the development and deployment of new HDSL2-based solutions, and will move the industry toward interoperability.
Parameters of the New Standard
Current two-pair HDSL, based on the 2B1Q line code, was developed in 1992. It is now used throughout the world by LECs and network service providers for deploying T1 (1.544 Mbps) and E1 (2.048 Mbps) services. HDSL continues to enable significant reductions in installation and operating costs for network service providers by eliminating the need for T1 and E1 repeaters and specially conditioned lines. Currently, HDSL delivers either 1.544 Mbps or 2.048 Mbps over two twisted pairs at distances up to 12,000 feet.
PairGain, Level One and ADC are defining a line code, modulation and forward error correction scheme that provides the same performance and service distance over a single line that HDSL currently provides over two lines. A central component of the new standard is a spectrally-shaped waveform that does not interfere with existing T1, HDSL or ADSL (Asymmetric Digital Subscriber Line) services, while providing good performance even in worst case environments containing a mixture of other signals. Recent proposals for HDSL2 have not been able to make this claim.
This solution provides enough noise margin to operate simultaneously in a 50-pair cable bundle with crosstalk noise from the other services. This HDSL2 solution has evolved from extensive noise modeling and has more than 6dB of noise margin in worst case mixed crosstalk scenarios. While spectral incompatibility has hampered other DSL technologies, the HDSL2 breakthrough developed by these companies will enable network service providers to install it without the need to upgrade or redesign their cable plant.
"ADC's commitment to next generation DSL standards is important to our customers," said Lonnie Martin, President, Network Services Division, ADC Telecommunications. "Our long-term participation with Level One and our contribution to the standards development of HDSL2 framing and transmission will help ensure that ADC will continue to provide our customers with the latest DSL technology in the form of a platform delivering the best value for their entire suite of T1-based services."
"As we demonstrated with our original HDSL consortium, Level One is committed to developing standards and products that enable reliable, high speed transmission in today's network environment," said Level One President and CEO Robert Pepper. "By combining our simulation and implementation expertise with PairGain and ADC's knowledge and understanding of the system demands, Level One intends to deliver a silicon solution that meets the new challenges required for HDSL2."
"We expect that the unique combination of having the world's largest installed base of two-pair HDSL systems, coupled with our systems and microelectronics expertise will shorten the time to market of this new technology," said Howard Flagg, PairGain's president. "We are looking forward to providing our customers with an HDSL2 solution that will allow interoperability across multiple platforms."
Demand for Additional Bandwidth
The demand for T1/E1 services is now growing at substantial rates due to the rapid growth of the Internet, and service providers require an enhanced HDSL technology to provide these same data rates over a single copper pair. Existing copper pairs in the network are becoming scarce and new technology must be developed to allow more efficient use of the copper infrastructure.
These recognized leaders in HDSL equipment, systems, and silicon will combine resources and efforts to deliver a complete specification proposal to the T1E1.4 working group, the ANSI committee responsible for selecting the new HDSL2 standard. Other system and semiconductor companies interested in endorsing this new standard are also invited to participate.
The new HDSL2 standard is to be discussed at the June 30, 1997 interim meeting of the ANSI T1E1.4 working group.
About the Companies
These three leading telecommunications companies bring extensive experience of over more than a decade in the deployment of DSL systems. Their engineers understand the key issues required for defining new DSL line codes and modulation schemes. All three have strong system simulation, DSL design expertise and implementation capabilities. Collectively they have demonstrated their leadership by presenting numerous technical papers at DSL standards organization meetings.
PairGain Technologies Inc., the xDSL (High-speed Digital Subscriber Line) market leader, designs, manufactures and markets xDSL systems that allow network service providers and organizations with private networks to more efficiently and quickly deploy high speed digital services to end users over the existing infrastructure of unconditioned copper telephone lines.
ADC Telecommunications, Inc. designs, manufactures and markets a wide variety of transmission and networking systems and broadband connectivity products for fiber optic, twisted pair, copper, coaxial and wireless broadband global networks. The company's products are used by telephone companies, other public network providers (such as wireless, broadcast and cable TV operators) and private voice, data and video network providers. ADC provides DSL-based solutions with its Soneplex(TM) and Cellworx(TM) system platforms.
Level One Communications provides "Silicon Connectivity Solutions" for high-speed digital signal telecom and networking applications. These components are critical connecting links in today's telecommunication and data communication (LAN/WAN) networks and are the key building blocks for the Intranets and Internets of the future. Level One combines its strengths in analog and digital circuit design, with its communications systems expertise, to produce mixed-signal solutions with increased functionality and greater reliability, resulting in lower total systems cost. Level One Communications, Inc. is registered to ISO 9001 by Underwriters Laboratories, Inc. under accreditation by Raad voor Accreditiatie (RVA), the Dutch Council for Accreditation, and by ANSI-RAB. This accomplishment illustrates the company's commitment to world-class standards and dedication to providing the highest quality products. Company headquarters are located at 9750 Goethe Road, Sacramento, CA 95827. For information on the company and its products, visit its site on the World Wide Web at level1.com. |
