Accession Number : ADP003533

Title :   Transportability of Nebula Software,

Corporate Author : CARNEGIE-MELLON UNIV PITTSBURGH PA DEPT OF COMPUTER SCIENCE

Personal Author(s) : Steele,G. L. , Jr

Report Date : NOV 1982

Pagination or Media Count : 11

Abstract : This article discusses various aspects of the Nebula architecture definition that are purposely implementation-dependent. These might seem at first glance to present obstacles to software portability. These implementation dependencies are intentionally included in the architecture definition to allow implementors the freedom to evolve new implementation strategies and to exploit advancing technology. Portability problems are alleviated by a combination of specification conventions, explicit protection mechanisms in the hardware, and special modules that can be conventionally used to hide implementation details. The result is an architecture definition that allows Nebula software to be compatible across a range of hardware implementations, while enabling more cost-effective hardware realizations by allowing implementors the freedom to explore a variety of implementation techniques. (Author)

Descriptors :   *Computer program verification, *Computer architecture, Transportable, Compatibility, Cost effectiveness, Modules(Electronics)

Distribution Statement : APPROVED FOR PUBLIC RELEASE