The computer is a device capable of executing a well-defined sequence of operations prescribed/set up by the program. The notion "computer" is broader than the notion of "electronic computing machine" (ECM), as in the latter the emphasis is (placed) on calculations. The personal computer (PC) is distinguished by the fact that it can be used by one person without resorting to the help of a crew of service/maintenance personnel and without allocating a special room/space with the devices for climate maintenance, a powerful (?) power supply system, and other attributes/devices of large computers. This computer is usually aimed at interactive interaction with one user (in games, sometimes with two); moreover, interaction occurs through a variety of communication environments - from alphanumeric and graphical dialogue using the display, keyboard and mouse to virtual reality devices, in which, as for now, only smells are, probably, not involved.
The first computer, in which the principles of von Neumann were embodied, was created in 1949 by the English researcher Maurice Wilkes. Since then, computers have become much more powerful, but the vast majority of them are architected in accordance with the principles outlined in the report by John von Neumann in 1945.
In his report, John von Neumann described how a computer should have been structured in order for it to be a universal and efficient device for processing information.
First of all, the computer must have the following devices:
• an arithmetic logic unit, which performs arithmetic and logical operations;
• a control device, which organizes the process of program execution;
• a data storage device, or a memory for storing programs and data;
• external devices for input / output of information.
Computer memory should consist of a number of numbered cells, each of which can contain or process data or program instructions. All memory/storage cells should be easily accessible to other computer devices.
In general terms, the work of the computer can be described as follows. First, a program is entered into the computer’s memory using an external device. The control unit reads the contents of the memory cell where the first instruction (command) of the program is located, and organizes its execution. This command can specify the execution of arithmetic or logarithmic operations, reading data from memory to perform arithmetic or logical operations, or writing their results into memory, entering data from an external device into memory or outputting data from memory to an external device.
As a rule, after executing a single command, the control device starts executing a command from a memory cell, which is located immediately after (behind?) the command, which has just been executed. However, the order can be changed using control transfer (transition) instructions/commands.
These commands instruct the control unit to continue the program execution, starting with the command contained in some other memory location. Such “jump”, or transition, may be executed in the program not always, but only under certain conditions, for example, if some numbers are equal, if the result of a previous arithmetic operation has turned out to be zero, etc. This allows to use the same sequence of commands in the program many times (ie, organize a cycle), execute different sequences of commands depending on the fulfillment of certain conditions, etc., i.e. create complex programs.
Thus, the control device executes the instructions of the program automatically, without human intervention. It can exchange information with the random access memory and external computer devices.
Text 8.
Word list
1. Service Level Agreement (SLA) - Соглашение об уровне предоставления услуги
2. security breach – нарушение системы безопасности
3. malicious user – злоумышленник; злонамеренный пользователь
4. leakage of data – утечка данных
5. data loss – потеря данных
6. unauthorized person – постороннее лицо
7. to modify data – изменять данные
8. strong authentication practices - надежные механизмы аутентификации/опознавания пользователя
9. hijacking of sessions – перехват сеанса (связи)
10. phishing – «фишинг», интернет-мошенничество с целью хищения личных данных
11. user credentials – учетные данные пользователя/данные для авторизации пользователя
12. legitimate user – зарегистрированный пользователь
13. internal controls – внутренние механизмы контроля
14. National Institute of Standards and Technology (NIST) - Национальный институт стандартов и технологий
15. metrics – параметры, показатели
16. to mitigate threats – смягчить/ослабить угрозы
17. to outsource services - пользоваться услугами сторонних специалистов/компаний
18. private infrastructure – частная инфраструктура
19. gateway – сетевой шлюз
20. broker – программа-посредник
21. scalability – масштабируемость
22. integrity monitoring – мониторинг соответствия принципам добросовестности
23. malware protection – защита от вредоносных программ
24. service provider – оператор связи
Text 7.
Word list
1. revenues - доходы
2. performance level – уровень эффективности / производительности
3. pricing mechanisms – механизмы ценообразования
4. Processor Sharing (PS) (scheduling policies) – (планирование?) разделение процессорного времени
5. arrival rate – интенсивность входного потока
6. end-user – конечный пользователь
7. cloud paradigm – модель/концепция облачных технологий
8. warranty – гарантия
9. multi-tenant model – многопользовательская модель