 Welcome to the session on Fline's classical taxonomy. At the end of the session students will be able to distinguish Fline's classification for computer architecture that are based on the number of instructions and data string. The Fline's classification of computer architecture is mentioned. The one widely used since 1966 is Fline's taxonomy. This taxonomy distinguish multiprocessor computer architecture according to independent dimensions of instruction stream and data stream. So instruction stream is sequence of instructions executed by machine and a data stream is sequence of data including input partial memory or partial data or temporary results used by instruction stream. Each of these dimensions can have only one of the two possible states like they are either single or multiple. So Fline's taxonomy is based on these two keywords will divide into single instruction, single data, single instruction, multiple data, multiple instruction, single data or multiple instruction and multiple data. So one by one these Fline's taxonomy classification we will check it out in the next slide. So with respect to data stream and the instruction stream here if you are observing the machines which are based on SISD they are considered like uniprocessor. If we are observing SIMD machines these are vector processor or parallel processing machines. If you are looking MISD that is multiple instruction single data they are maybe pipeline computers and MIMD or the multi computers and multi processing machines. So in the SISD kind of structure here you can able to check it corresponds to the traditional mono processor that is Van Neumann based type of computers. A single data stream is being processed by one instruction stream that is at one time there will be we are going to execute one instruction. So single processor computers consisting uniprocessing kind of system in which a single stream of instruction is generated from the program. So here in the figure it execute the execution of instruction is SISD processor. So the figure is represent organization of simple SISD computer having the control unit, one processor unit and one memory unit. And in another figure the SISD processor organization they are also called scalar processor that is one instruction at a time and each instructions have only one set of operand. So single instruction only one instruction stream is being acted on by the CPU during any one clock cycle and single data that is only one data stream is being used as input during the one clock cycle. So instructions are executed here sequentially. Now in SISD machine instructions are proposed in a sequential manner and computers adopting this model are popularly called sequential computers. So most conventional computers have SISD architecture. All the instructions and data to be processed have to be stored in primary memory. So the speed of the processing elements in the SISD model is limited that is here it is dependent by the rate at which the computer can transform information internally. And the dominant representation here like IBM PC and workstations fine. Now I am moving to the second classification SIMD. So a type of parallel computer very important keyboard that is a type of parallel computer a single instruction that is all processing units executes the same instructions issued by the control unit at any given block cycle. So multiple processor executing instructions given by one control unit. Multiple data that is each processing unit can operate on different data elements here as you are looking in the figure. So the processors are connected to shared memory or interconnection network providing multiple data to processing the units. So an SIMD system here it is a multiprocessor machines capable of executing the same instruction on the CPU but operations on different data streams. So machine based on SIMD model are well suited to scientific computing purpose. So the information can be passed to all the processing elements that is different processors. Organized data elements of vectors can be divided into multiple sets and each processing element can process one data set. And the representatives like Cray vector processing machine. So here you have a question what are the two streams of planes Texanomi which are can be either CDL or parallel. So you have the four options. So you have your options option choice is D that is in 1966 Michel Fline proposed a classification for computer architecture based on instruction stream and data stream. Now we are moving for the third classification that is MISD multiple instruction stream and single data stream where each processor executes a different sequence of instructions. And in case of MISD computers multiple processing units operates on one single data stream. And in practice the kind of organization has never been used. Still let us check the architecture part. So here a single data stream is fed into multiple processing units. Each processing units operates on the data dependent via independent instruction stream as shown here in the figure and single data stream is forwarded to different processing units which are connected to different control unit and execute instruction given to it by control unit to which it is attached. So an MISD computing system it is a multiprocessor machine capable of executing different instructions on different processing elements but all of them operating on the same data sets. And the system performs different operations on the same data set. Machine built using the MISD model are not useful in most of the application. So though it is not used too much in the commercial part. So we will move for the last classification and check how good it will be. So in MIMD that is multiple instruction stream and multiple data stream. So here each processor has separate program and instruction stream is generated from each program each instruction operates on different data. So the last machine type builds the group of the traditional multiprocessor. Several processing units operates on multiple data stream. So here we can able to check multiple data stream and multiple instruction stream. The most for example here this is the current supercomputers or like a parallel computer read. So through the figures we will check multiple instruction is every processor may be executing a different instruction stream. Multiple data is like every processor may be working with the different data stream as shown here in the figure. So multiple data stream is provided by shared memory as can be categorized as loosely coupled or tightly coupled depending on the sharing of data and control execution can be synchronous or asynchronous. So an MIMD system is a multiprocessor machine which is capable of executing multiple instructions on multiple data set. And each processing element here in this model has separate instruction and data stream therefore machine built using this model are capable of any kind of application. So here I have some my references and specifically here I am going to use Ky-Hong.