Figure: SIMD Organisation

Single Instruction and Multiple Data stream (SIMD): In this organisation, multiple processing components work under the control of a single CU. It has one instruction and multiple data stream. All the processing components of this organization obtain the similar instruction broadcast from the Control Unit. Main memory can be splitted into modules for producing multiple data streams performing like distributed memory as shown in Figure below. So, all processing components at the same time execute the similar instruction and are called as 'lock-stepped' together. Every processor acquires the data from its own memory and therefore it has on separate data streams. (Some systems provide a shared universal memory for communications too.) Each processor should be permitted to complete its instruction before the subsequent instruction is engaged for execution. Therefore, the execution of instructions is synchronous. Illustrations of SIMD organisation are DAP, PEPE, BSP, STARAN, MPP, ILLIAC-IV and the Connection machine (CM-1).

This kind of computer organisation is represented as:

Figure: SIMD Organisation