Heterogeneous network-based concurrent computing environments

Concurrent computing on networks of heterogeneous machines has gained tremendous attention and popularity in recent months. This computing model encompasses a wide spectrum of environments, ranging from very coherent systems to loosely coupled workstations, but usually excludes distributed operating systems. Many such systems are operational (several more are under development) and have been used for an impressive range of applications. Heterogeneous network computing environments have the potential for multi-gigaflop performance, provide excellent support for applications with multifaceted requirements, enable straightforward provisions for fault-tolerance, and are easy to install, maintain, and use. These systems enhance the power, versatility, and usefulness of existing hardware, and support well-understood, pragmatic, programming models. In this paper, we will survey the state of the art in heterogeneous network computing, beginning with a description of representative systems and applications. We will also attempt to identify the most pressing needs as well as the foreseeable obstacles, and pose a sampling of the major challenges that face researchers and developers in heterogeneous network computing.