Research Assistants: S. Wang, S. Li
Sponsors: NSF, AT&T
The availability of a variety of communication and networking technologies has created a great deal of interest in large scale global distributed systems with a wide variety of communication bandwidths and heterogeneous characteristics.
Experimentation with such a system is difficult, especially on the publicly available Internet. The difficulties include the lack of resources for individual researchers or research groups, lack of controls in the publicly shared long-haul networks, the increasing number of procedures when multiple administration units are involved, and the unpredictable dynamic nature of the Internet.
The objective of this research is to develop a software experimental facility. We have developed a WANCE (Wide Area Network Communication Emulation) tool which can emulate a WAN testbed. WANCE tool has been successfully applied to study the behavior of algorithms involved in transaction processing.
We have conducted experiments for round trip times, probability of lost datagrams over 1800 sites across US over 500 networks. We have measured these parameters for networks and sites in Hong Kong, China, Japan, Finland, Switzerland and India. The effects of these measurements on the design of commit protocols, replication mechanisms have been investigated. This research has application in airline reservation systems, international banking, and other transaction processing applications.