Gigabit Research Testbeds

Gigabit Research Testbeds
Today, gigabit testbed facilities are being developed, and work on the gigabit network applications has begun. However, the classical “chicken and egg” problem applies to gigabit networks in the sense that they won’t be economically viable until a market for them exists and a market won’t develop until user have a chance to experiment with such higher-speed networks.
The NSF established several testbeds to provide a focal point for needed technical interaction that is driven by user needs. These testbeds have pioneered some of the technical discussion and publications concerned with the evolving architectures. The initial goals concentrated on end-to-end upper-layer issues (user impact, applications, transport & higher-layer protocols, operating systems, and host network interface architecture best suited for imaging, visualization, multimedia, remote backup, and other emerging applications) So that usage of networks is understood.
The current gigabit research revolves around a set of six testbeds (Aurora, blaca, CASA, MAGIC, Nectar, and VISTA net) funded by the NSF and the Defense Advanced Research Projects Agency, each with its own research objective and staff. Here are some details of the six NREN testbeds:
Aurora. The network links four sites located in the Northeast using 622-Mbps SONET (data transmission standard) channels ; the university of Pennsylvania in Philadelphia; Bell core in Morristown, New York, and the Massachusetts Institute of Technology in Cambridge, Massachusetts. This testbed will explore alternative network technologies, investigate distributed system / network service paradigms, and experiment with gigabit network applications. A key objective is to provide a platform on which other researchers can explore both business and scientific applications of such net works as well as develop the network architecture to meet the needs of these new applications.
Blanca. The network connects sites at AT&T Bell Labs in New Jersey; the University of Wisconsin and the University of Illinois in the Midwest; and the University of California – Berkeley and Lawrence Livermore Laboratories in California. AT&T is providing long – distance T-3 circuits and experimental switches and hardware, and local exchange carriers are providing higher speed regional links. The emphasis will be on widely distributed supercomputing and high – bandwidth visualization. Specifically, the applications to be studied include multiple remote visualization and control of simulations; radio astronomy imaging; multimedia digital library; and medical imaging.
CASA. The network connects four sites in California and New Mexico: the major ones being san Diego supercomputer center and the Los Almos National Laboratory. Network links are provided by MCI, pacific Bell and US west. Applications here focus on using gigabit networks to combine the processing power of multiple supercomputers for climate and chemical reaction modeling.
MAGIC. The network ties together a wide variety of government and university sites. Sprint and southwestern Bell are among the carriers providing links. The network will be used by the U.S Army and others to test interactive reaction modeling.
Nectar. The network will provide a high speed link between two local area networks at Carnegie – Mellon University and the Pittsburgh super – computer center. Fiber links will be provided by Bell Atlantic, and Bellcore and CMU are collaborating on hardware design. The network will link high – performance parallel interface LANs over ATM- and SONET – based networks.
VISTAnet. The network uses SONET / ATM links from Bellsouth and GTE to link supercomputer center MCNC, North Carolina State University, and University of north Carolina-Chapel Hill. The network focuses on a single application: networking powerful computer to help doctors plan radiation therapy for cancer treatment.
These testbeds are exploring two different technological approaches to developing gigabit switching systems: asynchronous transfer mode (ATM) and packet transfer mode (PTM). A prototype ATM switch was provided by Bell core, and IBM has provided a packet transfer mode switch. High – speed network links are provided by MCI, NYNEX, and Bell Atlantic. The first approach, ATM switching , uses small, fixed-size data elements (called cells) and is expected to form the basis for the next generation of network switching technology. The second approach, PTM, is based on variable-sized packets and is a method being purchased within a smaller segment of the data communications industry. Each approach has its advantages, and these and other options may coexist in the networks of tomorrow. In addition, technologies, as well as the development of higher-layer protocols and application service models, need further research.
3.5 GLOBALIZATION OF THE ACADEMIC INTERNET
By the late 1980’s the internet had spread globally, including Canada, Australia, Europe, South Africa, South America, Asia, and Japan. Although we have discussed the development, implementation, and network infra structure in the united-states, the Internet has always been an international network. Today the global network environment reaches over 140 countries, each with its own slant. Asian countries see the internet as way of expanding business and trade. Eastern European countries, longing for scientific, have long wanted to participate but were excluded by government regulation. Since this ban was relaxed, development is progressing rapidly. Third world countries that formerly did not have the means to participate now view the internet as a way to raise their educational expansion is hampered by the lack of a good supporting infrastructure, namely, a decent telephone system. In Eastern Europe and in several developing nations, a reliable phone system capable of handling continuous data transmission is virtually nonexistent. Even in major capital cities, fast connections are often limited to the speeds available to the average home anywhere in united-states, 9600 bps. Typically, even if one of these countries is “on the internet” only a few sites representing the top institutions have access-usually, the major technical university for that country. However, telecom infrastructure is a major priority in most developing countries and is expected to improve rapidly [NAS93].