Distributing time sensitive data in a COTS shared media environment

Traditionally, the Navy has developed systems which distribute time-sensitive data using specialized components such as dedicated point-to-point communications links. Today, however the Navy is moving away from specialized solutions and toward Commercial-Off-the-Shelf (COTS) components to both keep up with the rapid pace of technology changes and to reduce system costs. COTS components are designed to meet needs of applications in the general commercial marketplace, not the specialized needs of real-time applications. This paper examines the ability of COTS workstations to distribute and process time sensitive data in a shared media environment. Several metrics are defined and then used to evaluate the performance of a simulated time sensitive data distribution and processing mechanism running on COTS workstations from Hewlett Packard, the Digital Equipment Corporation, and Sun Microsystems. The data collected is analyzed. COTS real-time operating system features are then used to tune the performance of the client and server components of the mechanism.