CSC/ECE 506 Spring 2012/1c cl

Introduction

In computing, MISD (multiple instruction, single data) is a type of parallel computing architecture in which multiple processing elements execute from different instruction streams, and data is passed from one processing element to the next. The requirement that data is passed from one processing element to the next means that it is restricted to a certain type of computations, but is hard to apply in general. Pipeline architectures belong to this type, though a purist might say that the data is different after processing by each stage in the pipeline. Fault-tolerant computers executing the same instructions redundantly in order to detect and mask errors, in a manner known as task replication, may be considered to belong to this type.

Examples of parallel computer with MISD architechture

Few actual examples of this class of parallel computer have ever existed. One example of this machine is the systolic array, such as the CMU iWarp[Borkaret al., 1990]. Another prominent example of MISD in computing are the Space Shuttle flight control computers. The research on MISD concentrates on some conceivable usage: Multiple frequency filters operating on a single signal stream, Multiple cryptography algorithms, and Attempting to crack a single coded message.