Marjory J. Johnson

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Communication technology now makes it possible to support high data transmission rates at relatively low cost. In particular, optical fiber can be used as the medium in local area networks with data rates in the range of 100 megabits per second. Unfortunately, local area network topologies and communication protocols that work well with lower speed media(More)
Currently there is no control for real-time traffic sources in IP networks. This is a serious problem because real-time traffic can not only congest the network but can also cause unfairness and starvation of TCP traffic. In this paper, a new rate control scheme, RCS, is introduced for real-time traffic in networks with high bandwidth-delay products and(More)
This paper describes an experiment to prototype a new way of conducting science by applying networking and distributed computing technologies to an Earth Science application. A combination of satellite, wireless, and terrestrial networking provided geologists at a remote field site with interactive access to supercomputer facilities at two NASA centers,(More)
The effects of iron, zinc, copper, manganese, and Methocel on the growth of L cells in a synthetic medium were studied. The medium was iron-deficient unless a supplement of 1.0 g/liter Methocel HG (4,000 centipoises), Methocel ash equivalent to 1.0 g/liter Methocel, or 1.0 microM FeSO4 was added. Cells grew faster in the presence of FeSO4 or Methocel ash(More)
Development of the Next Generation Internet requires the development of revolutionary applications as well as advances in networking technologies. This paper presents experiences in using the NREN testbed to prototype a col-laborative medical-imaging application. Technological requirements for this application include high-bandwidth reliable multicast and(More)
File-transfer rates for ftp are often reported to be relatively slow, compared to the raw bandwidth available in emerging gigabit networks. While a major bottleneck is disk ID, protocol issues impact performance as well. Ftp was developed and optimized for use over the TCP/IP protocol stack of the Internet. However, TCP has been shown to run inefficiently(More)