A Portable Network-Transparent
Michael P. Zeleznik
Computer Science Department
University of Utah
This thesis describes the architecture of a portable, network-transparent
communication system (NTCS), which supports the message passing requirements
of a large class of distributed systems. These are large-grain,
loosely-coupled systems, distributed at the process level. The NTCS provides
interprocess communication, while isolating the application from issues such
as physical location, underlying communication details, and internetting. It
also allows for dynamic reconfiguration; processes can be transparently
distributed across different machines while running. By developing
applications around the NTCS, the design process is simplified and enhanced,
the resultant architecture can apply to a broader `class' of systems, and the
implementation will be less tightly bound to a single machine or set of
machines. For these reasons, this approach works well in testbed
Full implementations of this NTCS have been used extensively during its
development over the past two years, as the foundation of a distributed
information retrieval system testbed: the Utah Retrieval System Architecture
(URSA) project. The NTCS is built on top of the existing interprocess
communication system on each machine, following a cleanly layered design.
Except for a small, nonportable conversion layer, it is entirely portable.
Additional upper layers provide internet support, dynamic reconfiguration,
and a naming service. It was implemented in the C programming language.