World experience of ICT development

Lecture 1

Theme of the lecture:ICT role in key sectors of development of society. Standards in the field of ICT.

1.1. Introduction

1.2. World experience of ICT development

1.3. ICT Standards

The purpose of the lecture:

Introduction

Information and communication technologies for development (ICT4D) refers to the use of information and communication technologies (ICTs) in the fields of socioeconomic development, international development, and human rights. The theory behind this is, more and better information and communication furthers the development of a society.

Aside from its reliance on technology, ICT4D also requires an understanding of community development, poverty, agriculture, healthcare, and basic education. This makes ICT4D appropriate technology, and if it is shared openly, open source appropriate technology. Richard Heeks suggests that the I in ICT4D is related with "library and information sciences", the C is associated with "communication studies", the T is linked with "information systems", and the D for "development studies". It is aimed at bridging the digital divide and assisting economic development by fostering equitable access to modern communications technologies, and it is a powerful tool for economic and social development. Other terms can also be used for "ICT4D" or "ICT4Dev" ("ICT for development") such as ICTD ("ICT and development", which is used in a broader sense) and development informatics.

ICT4D can refer to assisting disadvantaged populations anywhere in the world, but it is usually associated with applications in developing countries. It is concerned with directly applying information technology approaches to poverty reduction. ICTs can be applied directly, benefiting the disadvantaged population, or indirectly, by assisting aid organizations, non-governmental organizations, governments, and/or businesses, to improve socio-economic conditions. The field is an interdisciplinary research area, quickly growing through a number of conferences, workshops and publications, but there is a need for scientifically validated benchmarks and results, to measure the effectiveness of current projects. This field has also produced an informal community of technical and social science researchers who rose out of the annual ICT4D conferences.

One of the main objectives of the ICT sector is the creation of a digital transport medium to support the processes of information, modern telecommunications infrastructure and its integration with the infrastructure of other states. Therefore, the development of transit potential in the sphere of information technologies, the integration of national economies into the global environment and act as an important task and a priority infrastructure identified in the strategy.

In order to develop promising technology areas to move to the next phase of industrialization, the task of further development of the Park of innovative technologies as one of the leading countries of innovation clusters.

Thus, the Head of State indicated task in the strategy "Kazakhstan - 2050" confirm the importance and the role of ICT in achieving the long-term growth of our state economy.

World experience of ICT development

Beginning in the 1980s, during the rise of the level of use of personal computers, as well as a consequence of increased demand for software products and completing formation of the different approaches of state policy towards the development of the ICT sector. Next, the transition to digital telecommunications in the 1990s and the subsequent formation of the Internet, the impetus to promote the further development of ICT in the world.

A lot of approaches to ICT development conventionally divided into two directions: the first - the development of ICT production and services (computers, software, devices, telecommunications and others.), In order to increase output and to strengthen ICT industry - "ICT as a manufacturing sector "; the second - the introduction of ICTs in different sectors of the economy, to maximize the information society and economy - "ICT as a tool of information society." Within these two areas can be classified in the following levels of strategic approaches: the development of the ICT sector, export-oriented; ICT sector development, oriented to the domestic market; approach global positioning; ICT as a tool for social and economic development . Consider these approaches on country practices.

Lecture 2

Topic of the lecture: Introduction to computer systems. Architecture of computer systems. The purpose of the lecture:

1.1. Basics of Computer Systems

1.2. Architecture of computer systems.

Computer - a universal (multi-purpose) device or system designed to nakopleniya, processing and transmitting information. Basic computer components: processor, memory, peripherals,

Under computer architecture refers to its logical organization structure, resources, that is, the means of a computer system that can be allocated to processing dannyh for a certain period of time.

Differ Princeton and Harvard architecture. These architectural options were proposed in the late 40-ies of experts, respectively, Princeton and Harvard universities in the US for future development of computer models.

Princeton architecture

Princeton architecture, which is often called the von Neumann architecture, characterized by using a common memory for storing programs and data, as well as for the organization of the stack. uses a common system bus through which the processor and receives commands and data for accessing this memory.

The architecture of modern personal computers based on

bus-modular principle.

 

Highway (bus system) - a set of electronic liny connecting the CPU, main memory and periferiynye devices together on the data transmission, signaling and memory addressing. The modular construction of the consumer himself can equip kompyuter configuration required him to produce at neobhodimosti its modernization.

The structural components of the system unit and pipe are located on the system board. Most computers have motherboards that contain only the basic components, and communication components, such as actuators nakopiteley, other peripheral and display information transmitted on the bus in parallel.

The data on the data bus can be transmitted from the processor to any device, or vice versa, from the device to protsessoru, ie a bidirectional data bus. The main modes of the processor using her missing devices. In this case, the missing elements are arranged on separate printed circuit boards, which vstavlyayutsya in special expansion slots provided for this purpose on the system board. These additional fees are called affiliates, and motherboard - motherboard.

Functional devices made on the child platah, often referred to as controllers or adapters, and themselves daughter boards - expansion cards. Thus, podklyuchenie individual computer modules to the highway, located directly on the motherboard, at the physical level by using the controllers, and software provided by the drivers. The controller receives a signal from the processor, and decrypts it to sootvetstvuyuschee device could take this signal and correctly otreagirovat him. For his performance of the processor is not responsible, it is responsible only appropriate controller, so periferiynye computer devices are replaceable, and a set of such modules is arbitrary. Most peripherals podsoedinyaetsya very simple - from the outside, through the connectors on the sistemnogo unit housing to the outputs of the respective controllers - ports (peripheral devices are also called external, because the computer communicate with the "outside world").

 

Modular organization system based on trunk (schinny) information exchange principle. The processor performs arithmetical and logical operations, is reacted with pamyatyu controls and coordinates operation of peripheral devices.

The exchange of information between individual devices kompyutera made by forming three mnogorazryadnym highway tires (Multiple communication lines), connecting all modules - data bus, address bus, control bus. Bus width determined by the number of bits the data bus are:

- Write / read data from RAM (Random zapominayuschee device - RAM);

- Write / read data from external storage devices (OVC);

- Read data from the input device;

- Sending data to output devices.

The choice of data exchange subscriber makes the processor to form the address code of the device, and for RAM - code memory addresses. address code transmitted on the address bus, the signals are transmitted along it in one direction - from the CPU to the devices (one-way bus).

By bus control signals are transmitted, defining the exchange of information harakter (I / O), and the signals sinhroniziruyuschie interaction devices involved in the exchange of information.

Any computing machine consists of three basic components:

• CPU,

• Memory,

• Input-output devices (UVV).

Information communication between computer devices via the system bus (highway system).

Clock speed characterizes the number of elementary operations on data transfer in one second. Bit line is measured in bits, clock rate - in megahertz.

Control unit (CU) generates a command address which is to be performed in this cycle, and outputs a control signal to read the contents of the corresponding memory cell (memory). The read command is transmitted to the CU. According to information contained in the address field team CU generates operand address and control signals for reading from the memory and sent to an arithmetic logic unit (ALU). After reading the control device for the operand operation code contained in a command, it outputs the signals to the ALU operation. The result is stored in the receiver's address on the result under the control of the recording signals. Symptoms result (sign presence overflow sign of zero, and so forth) are fed to the control device, wherein the special register is written in characters. This information can be used in the following program commands, such as conditional branch instructions.

The input device allows you to enter a program for solving the problem and input data into the computer and put them into memory. Depending on the type of input data input device for solving the problem are introduced directly from the keyboard, or they must be pre-positioned on a carrier (disk drive).

The output device is used for the output of the original computer information processing results. Most often it is the symbol information which is output via the printing device or a display screen.

The storage device or memory - a collection of cells for storing a code. Each of the cells is assigned a number called the address. Information recorded in the cell can be both in the machine as command and data.

Processing of data and commands performed by arithmetic logic unit (ALU) designed to direct machine instructions perform the action control unit. ALU and W together form a central processing unit (CPU). The processing results are transferred to the memory.

Basic principles of construction with the Von Neumann architecture

• The principle of duality. For the submission of data and commands using the binary system.

• Software management principle. The program consists of a set of instructions that are executed by the processor after each other in sequence.

• The principle of uniformity of memory. As the program (command) and data are stored in the same memory (and encoded in the same notation, often - binary). Above commands can perform the same actions, as well as on the data.

• The principle of memory addressability. Structurally, the main memory consists of the numbered cells, the processor at any given time is available for any cell.

• consistent program management principle. All commands are stored in memory and executed sequentially, one after another.

• The principle of conditional branch. the program commands are not always carried out one after the other. May be present in a program of conditional branch instructions (commands and function calls or interrupt) which alter the sequence of commands as a function of the data values. This principle was formulated long before von Neumann Ada Lovelace and Charles Babbage, but was logically included in the specified set as the previous complementary principle.

Von Neumann architecture has a number of important advantages.

• The presence of shared memory allows you to quickly redeploy its capacity to store separate sets of instructions, data, and the implementation of the stack, depending on the task. Thus, it is possible to more efficiently use the available RAM in each particular application.

• The use of a common bus for transferring commands and data greatly simplifies debugging, testing and monitoring the functioning of the system and increases its reliability.

Therefore, Princeton architecture for a long time dominated the computing.

However, her inherent and significant shortcomings. Chief among these is the need to sample the serial command and data to be processed by shared system bus. The total bus becomes a "bottleneck» (bottleneck - «bottleneck"), which limits the performance of the digital system.

Harvard architecture

Harvard architecture was designed by Howard Aiken in the late 1930s at Harvard University in order to increase the speed of computing operations and optimize memory performance. It is characterized by the physical separation of memory commands (programs) and data memory. In its original version it was used as a separate stack to store the contents of the program counter, which provides the ability to perform nested subprograms. Each memory is connected to a separate processor bus that allows simultaneous data read-write when the current command to sample and decode the next instruction. higher productivity is realized due to this separation flows of commands and data and reconcile their sampling operations than using Princeton architecture.



Disadvantages Harvard architecture associated with the need of a greater number of tires, and a fixed amount of memory dedicated to data and commands, the purpose of which can not be redistributed operative in accordance with the task at hand. Therefore it is necessary to use more memory, a coefficient of use in solving a variety of problems is lower than in a Princeton architecture systems. However, the development of microelectronic technology has substantially overcome these disadvantages, so Harvard architecture is widely used in the internal structure of modern high-performance microprocessors, which uses a separate cache for storing instructions and data. At the same time, the external structure of most microprocessor systems implemented the principles of the Princeton architecture.

- 2. A computer processor. Key Features (bit address space, etc.).

- CPU - is the central device of the computer. He vypolnyaet located in the RAM of the program team and "communicates" with external devices through buses address, data and control connected on a special chip contacts housing.

- The required components include processors arifmetiko logic (executive) unit (ALU) and a control unit (CU). Command execution processor predusmatrivaet: arithmetic, logical operations, transfer of control (conditional and unconditional), the movement of data from one memory location to another and coordinating the interaction of various computer devices. There are four stages of the processor processes the command: fetch, decode, execute, and over-pis result. In some cases, until the first team vypolnyaetsya second can be decoded, and the third selected.

- The fourth generation of CPU features computer executes the microprocessor (MP) - Very Large Scale Integration (VLSI), implemented in a single chip poluprovodnikovom (silicon or germanium), an area less than 0.1 cm2.

- Knowledge of the MP model, installed on the motherboard kompyutera, gives an indication of which class prinadlezhit computer equipment. Microprocessors differ in a number of important characteristics:

- - A clock speed of information processing;

- - Digit;

- - An interface with the system bus;

- Address space (memory addressing).

- An interface with the system bus;

- Address space (memory addressing).

Bit processor. This number of bits simultaneously obrabatyvaemyh processor, ie the number of internal bits (binary) bits - the most important factor proizvoditelnosti MP. The processor can be 8-, 16-, 32- and 64-bit. Along with the speed of the bit characterizes the amount of information processed by the computer processor for edinitsu time.

The address space (memory addressing). One funktsy processor is to move data in the organization of their exchange with external devices and memory. This processor generates a device ID, and for RAM - memory address. address code transmitted on the address bus. The amount of physical addressable memory microprocessor nazyvaetsya its address space. It is defined razryadnostyu external address bus. Indeed, let N - bit address bus, then the number of different dvoichnyh numbers that can be passed through it, is equal to 2 ^. It is known that the number of transmitted on the address bus when accessing protsessora RAM, is the address of RAM cell (its serial number). So, 2m - is the amount of RAM cells, which, using the address bus can address (adresovatsya) processor, ie 2m - the amount of address space of the CPU. Consequently, in 16-, 20-, 24- or 32-bit addresses generated shine address space, respectively 216 = 64 KB, 1 MB = 220, 224 = 16 MB = 232 4 GB. Therefore razryadnost often specify processor by writing, for example, 180386 - 32/32, which means that the MP has the 32-bit data bus and 32-bit address bus that is 32 bits simultaneously obrabatyvaet information and address space microprocessor is 232 == 4 GB.

 

Control questions:

1. What is called computer architecture?

2. What is the meaning of the modular principle of organization?

3. What is a pipe?

4. What is the function of the processor when the computer?

5. How is the subscriber's choice for communication?

6. What is the role of the control tires?

7. What are the basic building blocks are part of the computer?

8. Why can the modular principle of the computer?



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