| Back to logs list
Reprinted from alumni of the user at 13 o'clock on December 9, 2010 Reading (loading. ..) Comments (0) Category: Personal Diary
First, the choice
1, the first computer ENIAC Short was born in 1946, is a vacuum tube computer; second generation transistor computer; the third generation of small and medium scale integrated circuits; the fourth generation of large-scale integrated circuits;
2, the computer application areas are: scientific computing; information management; real-time control; office automation; artificial intelligence, network communication; e-commerce; aided design (CAI); aided design (CAD);
3, the computer representation of binary information, it uses the Von. Neumann principle the idea, that the form of two numbers 0 and 1 for the show, Commonly used conversion units: 1 B === 8bit; 1KB ==== 1024B; 1MB ==== 1024KB; 1GB === 1024MB; 1TB === 1024GB; 1 characters === 2B;
4, binary conversion rule: when the decimal into a binary check in addition two SHE; binary into octal when the three as a group, the weight is equal to three octal into a weight in the binary into hexadecimal Time for a group to four;
5, the character code, ASCII code is commonly used in Chinese meaning for American Standard Code for Information Interchange; by the International Organization for Standardization ISO adopted the role of common information exchange standards.
6, composed of the computer's system software and hardware system composed of two parts;
7, hardware systems, including computing, controller, memory, input and output devices, controllers and operators synthesized in the central processing control the CPU, main memory and external memory within minutes; memory is divided into read-only memory (ROM) and random access memory (RAM), the contents of the lost power is the RAM, external memory are hard (GB), floppy disk ( 3.5-inch, 1. 44MB), CD-ROM (650MB or so), removable storage flash drive (MB), MP3 (MB), etc.;
8,
tory burch reva, the software that runs on a variety of hardware devices and related procedures information. There are system software (operating system, language processing, database management systems) and application software that is practical procedures (such as WPS, OFFICE, PHOTOSHOP, etc).
9, the measure of computer performance are:
10, experienced the development of computer language to machine language, assembly language, high-level language; computer can identify the language is the computer language;
11, displays a screen display resolution is the number of pixels to display, is a computer product price key indicators of good or bad. There are common sizes: 640 * 480 800 * 600,1024 * 768
12, the printer main stylus printer, inkjet, laser printers;
13, boot ways: cold start : power, boot into the system; hot start: CTRL + ALT + DEL, End Task can also be used; reset the start method: RESET button;
14, a computer virus is: a man with the preparation of self-replication invasion by hiding unauthorized executable programs and data files, the impact and damage the computer's security procedures; copy and destructive, hidden, infectious;
15, a common virus characteristics: the computer starts over usually too slow to run exception; a regular occurrence of anomalies; access device does not respond when a long or unusual, such as a printer can not be online, garbage, etc.; disk space suddenly become smaller, or does not recognize the disk device; procedures and the mysterious loss of data, File names can not identify; display information and inexplicable anomalies; frequent crashes, restart, does not start; executable file size changes and hidden files of unknown origin occurred;
16, a computer virus removal: manual mode (DEBEG) anti-virus software (Rising Antivirus. KV3000, Connaught Shield)
17, access to the device is a modem (MODEM), the computer will recognize the digital signal and telephone lines for transmission of analog signals into recognition;
18, disk formatting commands (FORMAT), the disk can be rewritten, the information is lost; FDISK the partition command, you can change the disk logic;
19, computer network refers to the use of communications lines and communications equipment will be distributed in different geographical locations, having individual functions computer systems connected to each other in the network software support, to achieve data communication between each other and share resources; so the maximum use of the network also aims to facilitate data sharing;
20, according to the network location different from the ordinary into local area network (LAN), metropolitan area network (MAN), wide area network (WAN); by topology generally divided into: star, bus, ring, hybrid;
1. the following is not a computer network extension Park structure is ()
A single network structure B structure C bus structure D star structure
2. 16 * 16 lattice font in the font each character code stored number of bytes required for the ()
A 32 B 256 C 4 D 2
3. in computer, VGA means ()
A computer model keyboard model B C D display type display standard
4. digital camera belonging to the external device ()
A secondary storage device output device B C D random input device storage device
5. the following store, read and write speed from fast to slow is ()
A RAM B C CD D floppy disk
6. microcomputer hardware, the core of the system part is (CPU)
7. to the amount of MIPS Computer index with a ()
A word processing speed B C D transfer storage capacity Rate
8. The following options, is not part of computer viruses (immunity)
9. computer network's goal is (resource sharing and information transfer)
10. can be input device can also be for the output device is (hard drive)
11. The following are computer input (mouse, keyboard, bar code readers, cat's eye,), outputs (monitors, printers, graphic form, printing devices), storage device is ( hard drives, floppy disks, CDs, mobile memory)
12. At present, the computer representation of the application areas; scientific computing, data processing, process control (Computer Aided Engineering CAI)-aided design CAD
13. on the description of storage the right is (1MB = 1024 * 1024Bytes)
14. a computer to be connected to the Internet must install the hardware (modem modern)
15. computer necessary input and output devices are (keyboard and display )
16. in computer, transmission, storage, processing data and instructions are (binary code)
17. The following description of the error on the operating system is the (operating system and hardware as an application contact close relationship with the hardware)
18. computer data processing, the first transferred the data (memory)
19. a computer's word length is 4, the computer can handle the data bits are (32)
20. monitor key performance indicators (resolution)
21. microcomputer Pentiun4 1G, 1G said why? (CPU speed)
22. In computer, all information is (binary)
23. A complete computer system includes (hardware and software systems)
24. TCP / IP includes the three important Service Software: TELNET (terminal protocol simple process), FTP (Internet File Transfer Protocol), SMTP (Simple Mail Transfer Protocol) ip address form by the 32-bit binary number, divided into four groups, each 8 bits, each maximum 256, so the interval 0 ---- 255;
25. computer network's goal is to achieve the Interner have every computer on a domain name, to distinguish each computer on the Internet, in the domain name The maximum area code for the domain name: China: CN, Japan: JP, Taiwan: TW. U.S.: US, Hong Kong: HK
26, the network transmission medium: (1) twisted pair, (2) coaxial cable, (3) Cable (4) wireless communication
26. Operating system is actually a group process, unified management of the computer they used for a variety of software and hardware organization of computer resources in a reasonable workflow, coordination between the various parts of the computer, the relationship between system and user.
27. operating system features a full account? Answer: The operating system has five functional areas within the memory management, processor management, device management, document management and operations management
28. Through the Internet to send or receive e-mail (E-Mail) should be the primary condition for each electron e-mail, (E-Mail) address, its correct form is
XXXX@XXX.XX
29. the left mouse button to set the pointer speed to the fastest habits and will be set to automatically hide the task bar and task bar clock hidden. (Start Menu / / set / / Control Panel / / mouse; My Computer / / Right / / shortcut menu / / Explorer / / Control Panel / / mouse) (Start Menu / / set / / of the State Bar and began menu)
30. set the keyboard character repeat delay of the longest and fastest flicker frequency characters. (Control Panel / / keyboard)
31. The system time to April 20, 2005 19:30 PM (Start Menu / / set / / Control Panel / / date and time; my computer / / right / / shortcut menu / / Explorer / / Control Panel / / date and time) (double-click the task bar time boxes / / dialog box)
32. in the C drive folder create a new folder named ABC and in the This creates an empty folder in the BMP image file AA.BMP (My Computer / / Explorer / / C: File menu / / New / / BMP images; the File menu / / rename)
33 . the C drive folder T + LETXT file deletion, and empty the Recycle Bin (My Computer / / Explorer / / C: / / select the file, delete) (right-click the Recycle Bin / / shortcut menu / / empty the Recycle Bin, or open the Recycle Bin / / empty the Recycle Bin)
34. found by searching D: in. WAV format sound files and copy them to C: GUANLI folder, GUANLI folder self;
35. Will be D: in the AA. BMP files to C: under, AA. BMP file system content from the desktop screen; (PRINTSCREEN command and cut function)
36. By anti-choice command D: The Non. DOC format selected (the first selected. DOC file, the Edit menu / / negative selection)
37. GUANLI in D, find the folder, and this share;
38. Using non-continuous Select the shortcut key to D: under. DOC file all the selected (use CTRL key)
39. view the folder's properties, and is set to hide, while the file attribute is set to visible; XX file is read-only attribute set ,; (select File / / menu bar / / property; or right-click / / property) (the menu bar / / tools / / View)
40. to hide the default file name extension is set to visible ; (menu bar / / tools / / View)
41. in the C disk under a new AAA. BMP files, and set the desktop background to C: AAA. BMP (Control Panel / / display; desktop, right-click on a blank / / property)
42. Will be D: by the name of the file under the re-arranged;
43. Set desktop disk protection program for three-dimensional text, and Set the text to bit (no restart) (Control Panel / / Regional Settings option)
46. EPsonLQ ----- 1600 k add local printers, and printer name is set to force the western suburbs of Jiaotong University.
47. add a new language input France and Singapore, and the sound box is set to minimum.
48. On the desktop, the new D: QQ. EXE files fast boot method, and the name EXE file shortcuts. Named EXE file to create a shortcut at the same level directory.
51. using the Start menu, search online neighbors 192.168. 0.254, AAA and folders on the machine under the folder to the NIT simulate the machine;
Second, word-processing problems 2, browse the web, open
www.sina.com / news / index.htm page, a picture will be downloaded to D:, the file name is a beautiful world.
1.1
1.1.1 Overview of computer information and information processing
● data reflect the objective situation, which can be maps, text, sound and other multimedia forms such as performance.
● digital information: only 0 and 1, said information code string, said digital information.
● computer is an information processing (processing) machines. Computer generally refers to digital computers, digital computers can receive and process the digital information.
● The information entered into the computer data and programs can be divided into two categories: the data is processed object; program is processing the data of the instruction string.
● Information processing refers to the encoding of information, storage, conversion, transmission, detection.
● The information a computer can handle text, numeric, graphics, sound, images and video.
1.1.2 The working principle and classification of computer
1. the computer works: stored procedures, one by one execution (by the Hungarian-American mathematician von. Neumann / Von Neumann proposed and put into practice.)
2. computers Classification:
● representation and processing of information by way of points: a digital computer, analog computer, digital and analog hybrid computer.
● Purpose by computer: a dedicated computer, general computer
● size and performance points by computer: supercomputer, mainframe, midrange, minicomputer, microcomputer
1.1.3 Development and application of computer
1. the development of computer profiles
● 1946 the first digital computer (ENIAC) come out (from USA)
● First Generation (46-57 years): the tube for the logic components, delay line or make a memory drum; generally used for scientific computing, and military aspects.
● Second Generation (58-64 years): the transistor logic components, mainly with the core memory, magnetic tape and begin to use and loaded with memory; the creation of high-level language.
● The third generation (65-71 years): the main function of integrated circuit devices, main memory using semiconductor memory; appeared in batch, time sharing and real-time operating system.
● fourth generation (72 -): the CPU, memory and the I / O interface to do in large scale integrated circuit chip. Applications are extremely broad.
2. computer features:
● fast speed - speed of operation, said the number of operations per second, has been as high as several billion times per second to hundreds of billions of times
● high precision - accuracy of the machine word, ie the data can be represented by (binary) of bits, has now reached 64.
● has a memory (storage) capacity - with a variety of memory to store information.
● has a logic function - for a non-judgment.
● high degree of automation and flexibility - with automated process control computer.
3. computer applications:
● Scientific Computing (aerospace, bridges, buildings)
● Real-time control (production lines, modern weapons)
● data processing (databases)
● Computer Aided design (CAD), aided manufacturing (CAM) and assisted instruction (CAI)
● word processing and office automation
● Artificial Intelligence (robots, smart vehicles)
● computer networks (Internet, campus network )
1.2 the number of computer system and encoding system is that the number of
number of methods and rules; coding is to solve all kinds of information according to what methods and rules that the issue into the 0,1 code string.
1.2.1 number system
1. binary notation
(1) decimal counting system: a 0-9 ten digital, every ten further.
(2) binary counting system: the only two digital 0,1, every binary one. (0 +0 = 0 0 +1 = 1 1 +0 = 1 1 +1 = 10)
(3) in octal notation: There are 0-7 of 8 digital, every eight further. (7 +1 = 10)
(4) in hexadecimal notation: a 0-9, A, B, C, D, E, F total of sixteen digital, every hexadecimal one. (F +1 = 10)
(5), said the number: (number) count system cases: (2BF) 16 (decimal number by default, do not add subscript.)
(6) of the binary number Map: Figure 1-1. (Write down? At the appropriate number)
Figure 1-1
2. Number system conversion between (the number should be entered into the computer are converted to binary)
(1) conversion of the binary system
to decimal number to the decimal system launched by the general formula (a bit is 0),
Poetry - Qzone log, the results can be calculated.
(2) decimal number into two, eight, hexadecimal
10 →? A → 8 a
8 → 2 with
(4) binary and hexadecimal number conversion
2 → 16 using the number system, less than four padded with 0.
16 → 2 a
1.2.2 ASCII code (American Standard Code for Information Interchange)
● letters, punctuation marks, special symbols and numbers as symbols, known as the character. These characters are unified by American Standard Code for Information Interchange, said, referred to as ASCII.
● ASCII code look-up table method (Appendix I on page textbook P311): ASCII code with 7-bit binary number (or the highest bit is 0 8-bit binary number) to represent; the table that the first 654 columns, rows that No. 3210, a total of 128 codes. Look-up table by then over reading.
● The size of the character ASCII code according to their size comparison. ASCII characters commonly used code (from small to big): a space - Digital - uppercase letters - lowercase letters
example: A look-up table of the ASCII code value is obtained (1000001) 2 = (41) 16 = 65; by the A F can be calculated from the ASCII code decimal value of 70 [a difference of 5];
under the table shows the ASCII code value of A [65] the ASCII code value than a [97] is small, the lower-case letters than ASCII code value big capital. Figure 1-2
1.2.3
character encoding to use 0,1
character code string, said that China developed a Chinese character Code for Information Interchange GB2312-80, referred to as the national standard code.
● National Standard Code Total characters 7445. A 3755 Chinese characters, Alphabetical order; two characters 3008, arranged by radicals and strokes.
● Chinese characters as more than the national standard code symbols are used for each two-byte (16 bit binary) code to represent.
1. GB Code: rows, columns, each 94 (0-93), with the first column after the double 7-bit binary number, ie the highest two-byte 0 (see Materials P77).
2. area code: GB binary code that is not very convenient, so characters can also be expressed in decimal area code.
● Area (line), bit (column) of the 94 (1-94), with the first zone-bit dual-two decimal number, less than two preceded by 0. area code
● Please see Appendix 2 P312 materials. Figure 1-3 is part of the area code table, such as: Fu 2403; the 2435; the 2487
Figure 1-3
3. Machine code: a computer representation of the actual use of Chinese characters within the code, in computer multi-purpose two-byte (MSB is 1) code as machine code.
4. three encoding conversion: (see Figure 1-4)
● the area code of the code and place the corresponding numbers were converted by the hex decimal +2020 H is the national standard after the code (which H said that 16 decimal);
● hexadecimal code +8080 H is the national standard machine code. Thus, two bytes of machine code necessarily the highest bit 1 (0 GB code).
Figure 1-4
example: characters of the area code 2083, the national standard code for the 1453H +2020 H = 3473H, machine code for the 3473H +8080 H = B4F3H.
1.3 computer, the computer's basic operations
calculated in two ways: numerical calculation (the most basic is the arithmetic) and non-numerical computation (basic logical operations.)
1.3.1 arithmetic
arithmetic is the most basic addition, other operations can be achieved by the addition.
binary addition rules: 0 +0 = 0 0 +1 = 1 1 +0 = 1 1 +1 = 10
binary multiplication rule: 0 * 0 = 0 0 * 1 = 0 1 * 0 = 0 1 * 1 = 1
1.3.2 of basic logic operations (P13 Table 1.2)
There are three basic logic operations: and (AND), or (OR), not (NOT). The following is a binary code
0,1, generally a recognition that the event (s), 0 for negative events (false).
1. logic and rules (when both A and B is true, A AND B is true, otherwise false.)
0 AND 0 = 0, n, 0 AND 1 = 0 nn1 AND 0 = 0 nn1 AND 1 = 1 (or 0? 0 = 0 0? 1 = 0 1? 0 = 0 1? 1 = 1)
2. logic or rules (if A and B when there is a true, A OR B is true, otherwise false.)
0 OR 0 = 0 nn0 OR 1 = 1nn1 OR 0 = 1 nn1 OR 1 = 1 (or 0 +0 = 0 0 +1 = 1 1 +0 = 1 1 +1 = 1)
3. the logic of non-rule (if A is true, NOT A is false; when A false, NOT A value of true.)
NOT 0 = 1 nnNOT 1 = 0 (inverted)
1.3 computer, the computer's basic operations
calculated in two ways: numerical calculation (the most basic is the arithmetic) and non-numerical computation (basic logical operations.)
1.3.1 arithmetic
arithmetic is the most basic addition, other operations can be achieved by the addition.
binary addition rules: 0 +0 = 0 0 +1 = 1 1 +0 = 1 1 +1 = 10
binary multiplication rule: 0 * 0 = 0 0 * 1 = 0 1 * 0 = 0 1 * 1 = 1
1.3.2 of basic logic operations (P13 Table 1.2)
There are three basic logic operations: and (AND), or (OR), not (NOT). The following is a binary code
0,1, generally a recognition that the event (s), 0 for negative events (false).
1. logic and rules (when both A and B is true, A AND B is true, otherwise false.)
0 AND 0 = 0, n, 0 AND 1 = 0 nn1 AND 0 = 0 nn1 AND 1 = 1 (or 0? 0 = 0 0? 1 = 0 1? 0 = 0 1? 1 = 1)
2. logic or rules (if A and B when there is a true, A OR B is true, otherwise false.)
0 OR 0 = 0 nn0 OR 1 = 1nn1 OR 0 = 1 nn1 OR 1 = 1 (or 0 +0 = 0 0 +1 = 1 1 +0 = 1 1 +1 = 1)
3. the logic of non-rule (if A is true, NOT A is false; when A false, NOT A value of true.)
NOT 0 = 1 nnNOT 1 = 0 (inverted)
1.4 computer system components
● computer system includes hardware and software systems in two parts.
● computer hardware system constitutes part of the collection of all entities; software system is the sum of the various procedures and documentation.
1.4.1
computer's hardware system hardware consists of computing, controller, memory, input devices, output devices five major parts.
1. calculator: computer arithmetic and logic operations of the main components.
2. Controller: Remove the command from memory control computer one by the coordination of the various components, it is the computer's command center.
3.
● computer memory storage components, used to store raw data and procedures.
● memory is a multiple of 8 bits or by storage units, each unit has a number, that address.
● bytes of storage capacity calculation:
A.8-bit binary number is 1 byte [byte] is denoted by 1B; 1024 [2 of 10 power] bytes recorded as 1KB; 1024KB record to 1MB; 1024MB recorded as 1GB.
B. byte unit conversion between: 1GB = 1024MB = 1024 × 1024KB = 1024 × 1024 × 1024B
● memory into internal memory (main memory) and external memory (secondary memory) are two:
A. memory is semiconductor memory, which can be divided into read-only memory (ROM) and random access memory (RAM) are two kinds of memory, usually referred to generally refers to RAM; external memory is mainly magnetic media memory, a disk (floppy, hard disk), tape,
tory burch sale, CD-ROMs and so on.
B. CPU can access directly to memory operations, and external memory data must be transferred to the memory to operate, so the memory is a computer information exchange center.
C. memory access speed, storage capacity is small, a power-down information to be lost; external memory access is slow, storage capacity, can be permanently stored data.
4. input device: the original data and programs into the computer can recognize 0,1 code string input to the computer.
common input devices are keyboard, mouse, microphone, scanner, light pen, teleprinter and so on.
5. output devices: the computer processed information into a familiar form or other identification information output device to the outside.
commonly used output devices are monitors, printers, speakers, plotters and so on.
Note:
● arithmetic unit controller and the computer's core components, said central processing (CPU)
● CPU and memory together are called the host.
● input and output devices and external memory referred to as an external device.
Note: Although disk drive storage devices, but there are dual function of the input and output, it can be used as input and output devices.
hardware structure shown in Figure 1-5 (Textbook P17); hardware work is shown in Figure 1-6.
Figure 1-5
1.4.2 PC hardware components
PC is short for personal computer is a micro-computer, IBM introduced the first IBM PC.
1.
host and the host inside the main chassis main board, interface card, external memory drives, power supplies, speakers, etc., as shown in Figure 1-7 and 1-1 show the video
(1)
PC host motherboard and its subsidiary circuits are mounted on a circuit board, known as the motherboard or motherboard, as shown in Figure 1-8.
most important components on the motherboard is the host, the CPU and memory, Figure 1-9 is the shape of CPU and memory.
CPU
CPU, two important indicators are word length and clock frequency. Word length reflects the PC can deal with the length of the data, marked by the computer's computation accuracy; clock frequency reflects the PC's speed. CPU performance index determines the grade of the computer.
memory
PC's main memory, ROM, RAM and Cache Three:
● ROM [read-only memory] can only be read but not written, the system used to cure some of the important procedures;
● RAM [random access memory] is the PC's main memory, causing memory inserted in the socket. Once the power down the computer, RAM is lost in all the information. Current configuration generally have 64MB, 128MB, 512MB or higher.
● Cache [cache]
A. To address CPU speed [increase is getting faster and faster] and memory speed [increase slower] does not match the bottleneck;
B. Cache is a higher speed and higher cost of random access memory, with memory and CPU, or between the two were equipped with;
C. memory in some of the data on the Cache, CPU read and write data, the first visit to Cache, not meet only access memory, which can improve data access speed, there are better cost performance.
some other
subsidiary circuit board, there are bus and a number of registers and control lines.
bus is a CPU data transfer between the various units within, CPU and external exchange of information channels.
registers are temporary storage of data or instruction storage unit.
(2) interface card expansion socket and the general configuration
● 6-8 expansion socket for connecting to peripherals and the host interface card (adapter) can be inserted in any expansion of the socket.
● different interface cards with different peripherals, such as graphics cards, network cards, sound cards, anti-virus card, graphics card, A / D, D / A converter cards. Are now generally sound card, floppy and hard drive controller card and other integrated on the motherboard, in order to reduce the interface card.
● video card alone to do in a circuit board, different types of graphics card to match with the corresponding display.
A. According to the display mode can be divided into MDA [Monochrome Display Card], CGA [color graphics card], EGA [Enhanced Graphics card], VGA [Video Graphics Array card], TVGA, SVGA card;
B. VGA graphics display resolution at least 640 × 480 pixels, color, select up to 256; TVGA and extended a number of characters SVGA display and graphic display of the new standard resolution up to 1280 × 1024, true color color can be achieved .
(3) disk drives and optical drives
● in the mainframe can hold up to two floppy and two hard drives or optical drive.
● They belong to an external device (external memory), it must be through the drive control card (or direct) to the host.
(4) Power
the mainframe can be installed on the AC power supply (electricity) is transformed into low voltage direct current for the mainframe and keyboard parts.
2.
keyboard keyboard is the main input device, and its own microprocessor, with on-off, decoding functions. Behind the keyboard and the host through the cable jack connected to the same color.
● essentials
A. keyboard keys and finger base keys: left hand A, S, D, F right hand, J, K, L,;
B. correct fingering (see video demonstration of 2 - 2)
● fingers division shown in Figure 1-10.
● essentials: a hand index finger J and F locate two keys (each with a small convex sets), followed by the other fingers in the appropriate key on the ride, ride in the space of two keys on the thumb, fingers with a recent knock Click the button, pay attention to hit back after the place.
● Do not apply excessive force, not to hold a key down; eyes try not to look at the keyboard, comfortably, regular exercise can be realized.
3.
mouse, the mouse is an important input device, divided into two keys and two three-button mouse, but they use the left and right keys. The mouse arrow in different circumstances have different shapes, that a different meaning, such as the funnel that the system is busy, please wait.
● Mobile: Do not move the mouse
● button drag: Hold down the left mouse button move the mouse
● Click and hold: Press the left mouse button. If not that, that left mouse button.
● Double-click: press the left button twice in rapid succession
● Right-click: Press the right mouse button
4. display
● main indicator is the resolution of the monitor, with the screen vertical and horizontal directions show point (pixel) number indicates. The higher the resolution, the displayed character and the picture becomes.
● Another indicator is the display color depth refers to the color with the point that the binary digits. The more bits, the richer the color layer, generally more than 16M color is called true color.
● screen size is the length of the diagonal, the commonly used 15
● Currently, there are two common monitor: CRT or flat screen monitors general, LCD liquid crystal display [no radiation], shown in Figure 1-11.
● Each display must be matched with the appropriate graphics card.
5. Printer
printer into three types: dot matrix printers, inkjet printers and laser printers, as shown in Figure 1-12.
dot matrix printer
● Principle: bumping, the print head with 24 steel needles click the dot matrix ribbon printing on paper.
● relative performance: low price, cost less; but the print quality is poor, noisy and slow.
● Common models: LQ-1600K and other inkjet printer
●
principles: non-impact, from a number of fine spray nozzle ink to the paper.
● Relative performance: lower prices, print quality, low noise; but the cost is big and easy to plug the nozzle.
● Common models: Cannon, Epson, Lenovo and other brands of laser printers
●
principle: the use of laser scanning technology to high-frequency modulated output signal, converted to dot matrix output.
● relative performance: speed, low noise, highest print quality; but the price is higher.
● Common models: Hp LaserJet 6L other
6. other external devices
scanners, plotters, the game sticks, digital cameras, digital cameras and so on.
7. external memory external memory
PC has a floppy disk, hard disk and CD-ROM drives.
(1) disk storage: floppy disk and floppy disk drive is the separation of
● magnetic media memory, according to the different diameter discs, floppy disks of 3.5 inch and 5.25-inch two (already out).
● speed: the speed of the floppy disk is low, only 300 rpm per minute.
● Capacity: 3.5-inch floppy disk has two recording magnetic surface, numbered 0 and 1; each magnetic surface has 80 tracks, from outside to inside numbered 0-79; each track divided into 18 sectors; Each sector can store 512 bytes of data. Shown in Figure 1-13, the capacity is: 512B × 18 × 80 × 2 ≈ 1.44MB
(2) hard disk storage: hard disk drives as one and sealed in metal box body. Hard to read and write speed, large capacity, long life, is the most important external memory computer.
● Hard-chip wafer from the steel alloy composition, surface deposited with a layer of magnetic media.
● Speed: hard disk read and write speeds much higher than the per minute up to 5400-7200 rpm. As shown in Figure 1-14, each side of each disc corresponds to a read-write heads, head suspended in the disk surface (Winchester technology), which read and write speed, and reduce the head wear.
● Capacity: hard disk performance by a number of the same size as the double-sided discs with a spindle fixed installation, the capacity is generally between 40-300GB.
Figure 1-14
(3) CD-ROM Memory: separation of the disc with the drive, the disc memory generally refers to the CD-ROM. Other types of drive are: CD-ROM burner CD-R, DVD, Combo COMBO [General] and so on.
● disc is a layer of aluminum plastic disk radiation, the use of optical storage technology, so the storage density.
● speed: CD-ROM drive and floppy disk read and write speeds ranging between, with the speed that a speed is 150Kbps, as is 40-speed, the data transfer rate of 150Kbps × 40. (Where b is bits, not bytes B)
● Capacity: typically 650-700MB. Although only a single store, but the most advanced DVD disc capacity has reached 150GB. CD-ROM and floppy
the use of methods such as video 1-3.
(4) high-capacity removable storage devices
● USB [OnlyDisk]: USB interface (hot), no drive, high-capacity memory. It features small size, light weight, larger capacity (64MB, 128MB, 256MB ... ... 2GB), access to faster, cheaper prices, has been gradually replacing the floppy disk.
● mobile hard disk: USB interface portable hard drive, the basic features of a fixed hard disk, as shown in Figure 2-12. Capacity 20-80GB, the price is more expensive.
1.4.3
computer software system software is the sum of all procedures and documentation.
1.
command and instruction system is the directive instructs the computer to perform an operation command. A collection of basic instructions the computer instruction.
instruction consists of two parts: operation code and operand address code. Opcode provides the computer to do what to do; address code that participate in the operation data and results of operations of the store location (only one address code simple and complex may have two or three), as shown in Figure 1-15. Figure 1-15
types of instructions: arithmetic instructions, transfer instructions, control instructions, input and output instructions, special instructions. 2. Program
program is an ordered set of instructions. 3. Programming language
(1) machine language
● machine in binary code, said set of instructions. It is the machine-oriented programming language.
● is the only way to directly identify the computer language. Run fast, but difficult to remember.
(2) assembly language
● mnemonic that the language used. Is machine-oriented programming language (low-level language).
● To be translated into machine language to run.
(3) high-level language
● close to human natural language programming language, which is highly process-oriented universal language.
● must be translated into machine language to run. Commonly used VisualC, VisualFoxPro, VisualBASIC, JAVA and so on. 4.
Software system software is the basic concept of a computer system for operation, maintenance, management and application of computer program and supporting documentation for all procedures combined.
Software Category:
shown in Figure 1-14 Figure 1-14 [blue part of the plan as a general understanding of the content]
5.
system software system software is running, management, maintenance the most basic computer software, generally provided by the manufacturer.
(1) operating system
operating system is the control and management of computer software and hardware resources, the rational organization of work processes and computer programs to provide a collection of man-machine interface.
main functions of the operating system: processor management, storage management, file management, device management.
(2) word processing program
or high-level language with assembly language program written as source code; code must be translated into a computer can deal directly execute the machine language program, called the target program.
language processing (translation) program has three:
● assembler: the assembly language source program translated into the target program execution after the translation process.
● interpreter: the high-level language source translation sentence by sentence, step through the translation process.
● compiler: the high-level language translation into the target program source code and connect again after the implementation of the translation process
(3) Utility: also known as support software, the machine maintenance, software development, software must tool.
6.
software applications for various types of software developed specifically problems. 1.4.4 PC's operating system
operating system is the most basic of the most important system software, operating systems have a greater impact MS-DOS/PC-DOS, UNIX / XENIX, and Windows categories.
1. from DOS to a WindowsXP
MS-DOS/PC-DOS
● DOS is the acronym for disk operating system, which is character-based single-user, single task operating system. As shown in Figure 1-15.
● DOS through expansion of the Western transformation, so that both deal with characters, while maintaining the original features of Western software, called DOS Chinese platform, also known as the Chinese system.
● DOS version from 1.0-6.22, Chinese platform CCDOS, SPDOS, UCDOS and so on.
Windows
● Windows is a graphical window interface based on the operating system.
● Windows version from the start Windows2.0, Windows3.X need to run DOS support;
● 95 years, released the Windows operating system Windows95;
● XP was released in WindowsXP, its network more powerful, faster, and good reliability.
● Windows95/XP biggest difference compared with the DOS is that multi-task operation; a single-user, multitasking operating system. In addition, it can also support voice, music, images and other multimedia information processing.
2. WindowsXP Windows operating system 1. WindowsXP operating system family
● WindowsXP Professional for personal computers
● WindowsXP Server for small and medium enterprises,
● WindowsXP Advanced Server for large enterprises, the server
● WindowsXP Data Center Server for large data warehouses, large server
2. WindowsXP features
● WindowsXP WindowsNT technology is based on multi-user, multitasking operating system.
● strengthening stability and security of the system to further enhance the network features.
● improve the system of hardware, software and network protocol compatibility.
● In addition to FAT, but has added a more secure NTFS disk partition format.
● enhanced multimedia support, improved system management.
● interface more friendly, WindowsXP / XP is bundled with IE5.0.
6. different grades of PC-P20 basic configuration
see Table 1.3
1.4.5 computer's performance indicators
1. frequency (clock frequency): the computer CPU clock frequency, to a great extent determine the computer's processing speed. Hertz, the current frequency as high as 3.0GHz.
2. the basic word: signs computer computing accuracy. The longer the word length, the precision is higher. Unit is the binary digits, usually with 16,32,64-bit word length.
3. Memory capacity: In general, internal, external memory capacity of the greater computer processing power, the stronger, faster, but must match the speed of the processor.
4. computing speed, system reliability, maintainability, compatibility, diagnosis, fault tolerance capabilities, command system function
5. cost performance: a variety of hardware and software performance and the higher price of the system the better.
computer teacher (395383764) 00:18:55
one multiple-choice (the big issue a total of 10 small problems, 每小题 2 points, a total of 20 points) Preparation of the four listed in the 每小题Only one option is to meet the subject requirements, please fill out the code in brackets after the title. The wrong choice, multiple choice or no choice points.
1. Modem data transfer rate is an important technical indicators, unit: ()
A.bps B. GB C. KB ; D. MB
2. and auxiliary storage compared to which of the following is the main memory (RAM) advantages: ()
A. access to relatively cheap prices fast B. ; C. D. large capacity is expensive
3.FTP ()
A. Secure Hypertext Transfer Secure Sockets Layer protocol B. File Transfer Protocol
C. D. Secure Electronic Transaction
4. IP sharing, also known as ()
A. B. virtual server virtual server client C. D. client
5. the uniform resource locator (URL) of the role is to ()
A. B. maintaining hypertext links to the information display C. D. service sends a request service
6. Standard Generalized Markup Language is ()
A. HTML B. SGML C. HTTP ; D. XML
7. Post Office Protocol is the abbreviation ()
A. HTTP B. SMTP C. IMAP D. POP
8. following a domain name that educational organizations are ()
A.edu B.gov C.net D.com
9. in the Internet, complete .)
A. Positive resolution Address Resolution B. D. C. reverse lookup domain name system
10. 100BASE-T standard specifies the NIC and HUB unshielded twisted-pair length between the maximum ()
A.50 m B.100 meters C.200 m D.500 m
computer teacher (395383764) 23:16:18
some theoretical problems (20 points)
one multiple-choice questions (1 point for each question , a total of 20 points)
1, CPU mainly by the computing device and controller, the following statements is correct ()
A, is mainly responsible for analyzing operational directive, and in accordance with instructions to make the corresponding op
B, is mainly to complete the operation data of the operations, including arithmetic and logic operations
C, the controller is responsible for analysis of instruction, and in accordance with instructions to make the corresponding op
D, the controller directly control the computer system Input and output operations
2, the following statements is correct ()
A, computer viruses can infect executable files
B, computer software is stored on a floppy disk in the process
C, The reason why the computer each time you start the same process, because all the information in RAM will not be lost in the shutdown
D, although the hard disk installed in the mainframe, but it belongs to external memory
3, the binary digits of a word is ()
A, 8 B, 16 C, 32 ; D, with the computer systems and different
4, the following statements is correct ()
A, will be converted into digital signals in analog communication lines to facilitate the transmission of signals, said for the modulation
B, in the form of intact information from the terminal into the communication line is called modulation and demodulation
C, in the computer network, a transmission medium can transmit multiple signals
D in the local computer, the only shared software resources, and can not share hardware resources
5, the use of ultra large scale integrated circuit manufacturing computer should belong to ()
A, the first generation ; B, the second generation of C, the third generation of D, the fourth generation
6, a storage capacity 1.44MB floppy disk, can store approximately 1.4 million ()
A, ASCII character B, Chinese characters C, disk file D, sub
7, the disk is write protected, then the disk data ()
A, can not be read, not excision, can not write new data
B, can be read, not excision, can not write new data
C, can be read out, can be excision, but can not write new data
D, can be read not excision, but it can write new data
8, CD-ROM is ()
A, feel the media B, that the media C, the performance of the media D, storage media
9, on the Internet (Internet), the electronic bulletin board is the abbreviation ( ;)
A, FTP B, WWW ; C, BBS D, E-mail
10, Windows in a minimized application window after the application ()
A, is still running in the background B, temporarily stop running C, full stop ; D, error
11, CPU processing is the basic unit of data words, a word of word length ()
A, to 8 bits ; B, is 16 bits
C, for 32 bits D, and the CPU chip type on
12, should be used to print the current screen content control key is ()
A, Scroll-Lock B, Num-Lock C, Pgdn D, PrtSc (Print Scorccn)
13,3.5-inch floppy disk, a corner piece has a sliding block, if Move the slider to reveal a small hole, the floppy disk ()
A, can not read but can write B, can not be read can not write C, only can read can not write D, can read and write
14, controls the function of ^ C ()
A, to terminate the current operation B, the system reset C, the standard output device to suspend the output D, the end of the command line
15, according to communications from the division, the computer network can be divided into local and wide area networks. The following are LAN network is ()
A, Internet B, CERNET C, Novell D, CHINANET
16, the two multi-media computer system component is ( )
A, multimedia cards and multimedia host
B, multi-media communications software and multimedia development tools
C, multi-media input devices, and multimedia output device
D, multimedia computer hardware system and multimedia computer software system
17, a variety of network transmission media ()
A, has the same transmission rate and the same distance ; B,
tory burch sandals, with different rates and different distance
C, has the same transmission rate and different distance D, with different transmission rate and the same distance
18, in the Windows, start the application the right way ()
A, pointing with the mouse icon in the application B, minimum into the application window icon
C, reduction of the application window D, with Double click the application icon
19, in Windows, the right to terminate the application execution is ()
A, the minimum application window into icon
B , the application window with the mouse double-click the Restore button in the upper right corner
C, with the mouse double-click the application window's title bar
D, the application window with the mouse double-click the top left corner of the control menu box
20, the so-called ; B, SBC
B, the computer is not equipped with any software ; D, only the operating system, computer equipment, operating questions
part (80 points)
Word part of the first question
huge cave is a huge cave in several layer. If the Buddha rock divided into three layers, Xing Shi Ruyan, Jiangsu Shan volume holes, Yichang nitrate hole, Guilin Seven Star Crags, are also three floors, Xingwen County of Sichuan Tianquan hole can be divided into five, and Beijing Shihua, has been known to have 6 layers, with the same Lichuan Dragon Cave, but it is speculated that geological data,
tory burch shoes, there are seven Shihuadong below, eight-hole. Become the largest cave found in layers. Multi-level cave that the place crust on the rise, a steady decline in water table, the initial formation of the tunnel continued into the dry hole, and up to a certain height, between the sinkholes through layers of holes.
those of some well-known cave room with tall domed topography, such as:
6 tunnel cloud chamber Beijing, Fujian, Yuhua Cave 6 caverns will be music, Sichuan 6 Xingwen Tianquan hole excavation, 6 Henan Gongxian snow cave tunnel, Tonglu Yaolin Wonderland 7 cavern, Longquan Cave Xuancheng 7 cavern, cave, Hebei Lincheng Zhi 7 cavern, Reed Flute Cave in Guilin, Guangxi 9 cavern, Icheon-dong Dragon Cave 10 rooms, 10 chambers Shaoguan Furong Cave.
complete the following requirements:
1, set the title text Align;
3, the text font for the fourth the first two paragraphs, indent the first line of the two Chinese characters;
4, arrangement of text using tab stops (tab stop position: 107 characters left, 15.71 characters left-aligned, vertical alignment of characters 20.71, 22.86 characters left justified, 35.36 characters left justified);
5, set the header text to and left-aligned.
6, after the name stored in its own named folder, file name: The second question
payment notice
user ID :3-4-12
said the number of the last: 498 Practical volume:
this: 524 Price: 3.00
shall pay this amount: Toll: Signature: (Seal)
complete the following requirements:
1, Set the table header text , 2.8 cm;
3, the first line of three cells combined, and using formula data into the table, set the amount of data format as currency format.
practical volume = this - last time, this amount of the fee paid * Price = utility;
4, set all the cells vertically aligned.
5, after the name stored in its own named folder, file name: Part
Excel workbook Sheet1 to open EXCEL sheet material, as required to complete the following:
(all calculated items, if calculated by hand filling, not to the point. all the decimal, are reserved 2 decimal places )
1, calculated water room rate position B16: I26;
7, category axis for the head of the household, the series for the water and electricity;
8, the chart background color set to blue color transition;
9, filled backdrop effect, choose the default 1, create a presentation, set to master the form.
2, the selected application design template, set the template for the slide show
3, enter the upper right corner in the title master,
4, set the slide's color scheme as the standard first.
5, insert two new slide.
6, the Save the presentation as to their own folder named after the file name:
Second, the terminology question (Question 5 of the largest small problems, 每小题 4 points, a total of 20 points)
1, the virus:
2, Encryption:
3, digital signatures:
4, TCP / IP protocol:
5, referred to as symmetric encryption method:
three short answer questions (a total of 6, the big issue of small problems,
tory burch 2011, 每小题 6 points A total of 36 points)
1, what is the IP address?
2, non-symmetric encryption?
3, what is computer network?
4, what is the OSI / RM?
5, What is a firewall?
6, what is the network operating system?
7.1
computer network computer network development and use of computer and communication technologies are product of the combination is an important part of the information highway.
7.1.1 the type of computer network
1. The definition and functions of the computer network
(1) the definition of the network is the computer network
interconnected with the aim of sharing resources, and independence a collection of computers.
(2) the basic functions of the network
● rational distribution and dispensing system resources.
● centralized data processing system.
● load balancing, collaboration, distributed processing.
● improve system security and reliability.
● rational allocation system, saving software and hardware equipment overhead.
● improve the system compatibility, user expanded to increase processing capacity.
● to provide users with various types of integrated services for users with a wide distribution of means of communication.
2. network classification
(1) come from the use of sub-scope or scale: local area network (LAN), metropolitan area network (MAN), wide area network (WAN).
local area network (LAN)
● LAN features
① coverage of a few hundred meters to several kilometers
② data transfer rate is higher than 1Mbps
③ is unique to a particular unit or department, such as the campus network. LAN computer network is the most active branches.
● LAN software platform
WINDOWS2000 (or NT) platform, UNIX or LINUX platforms.
MAN (MAN)
MAN features
① coverage to cover the entire city (generally known as LAN).
② data transfer rate of less than 1Mbps.
closed-circuit television (CATV) network is a typical example of MAN.
wide area network (WAN)
● WAN Features
① scope could involve tens of kilometers or more.
② data transfer rate is relatively low.
● WAN toward the Broadband Integrated Services Digital Network (B a ISDN) direction.
(2) from the information transmission bandwidth or transmission medium to sub: baseband, broadband network.
● baseband network transmission medium with a twisted pair, ribbon cable or coaxial cable, data transfer rate of 10Mbps or less.
● broadband coaxial cable using the protected data transfer rate up to 400Mbps.
used in the organization of the two LANs. Closed-circuit television (CATV) network is broadband local area network.
(3) from the sub-network function and structure: communication subnet, subnet resources.
● communication subnet is responsible for the transmission of information, including communications processors, terminal controllers, switches and transmission media.
● subnet in charge of information processing resources, including mainframe systems and terminals.
● Two channel communication subnet: point to point channels and broadcast channels.
● broadcast channel used primarily for local area networks, can be divided into static and dynamic categories.
7.1.2 computer network topology, transmission media and access control
1. topology of the network
(1) the concept of computer network topology, topology
: refers to the network communication line and ordering the geometry nodes to indicate the overall structure of the entire network appearance and the structural relationship between the modules.
● node (Node): Active devices connected to the network. Such as: computers, peripherals, communication control equipment. Divided into two categories:
relay nodes: for network connections. Such as: concentrators,
Ten home cooking practices - Qzone log, switches and so on.
access nodes (endpoints): includes a computer or terminal equipment and the corresponding connection lines from the source and destination of the role.
● link: information flow between two nodes carry the line or channel. Such as: telephone, telegraph lines or microwave.
(2) the classification of computer network topology
● Point to Point mode: star, ring, tree, fully connected model, cross ring, irregular six,
● broadcast : bus, satellite-based (radio type), three ring, as shown in Figure 7-3.
2.
● transmission medium for transmitting information transmission medium is a carrier of information from one node to another node to send the line entity.
● common transmission medium:
twisted pair: for point to point communication channel, low-grade local area network and telephone systems.
coaxial cable: used in high-end LAN and telephone system long distance transmission.
fiber: for high-speed local area network. As shown in Figure 7-4.
● Other transmission media: magnetic media (such as disk and tape), field of vision signals (such as microwave and infrared) and satellite communications.
3.
access control to solve multiple users competing for channel use right and reasonable to complete the allocation of transmission channel technology. There are three most commonly used
:
● IEEE 802.3 Bus access method
● IEEE 802.4 token passing bus access method
● IEEE 802.5 Token Ring passing access method
7.1.3 win2000 internal network use (slightly)
7.1.4 Internet and CERNET
1.Internet general
● 1993 the Clinton administration proposed the building of the United States the
● Internet, formerly known as Vision 1969, Planning Department, the U.S. Department of Defense (ARPA) to establish the ARPAnet (ARPANET), was first used for military trials.
● China's computing and network infrastructure (NCFC), in April 1994 formally connected to the Internet, establishing the nation's highest CN main domain name server settings.
● At present the international export of Management has the following four major Internet backbone network:
Chinese computing and network infrastructure projects (referred to NCFC)
China Education and Research Network (referred to as CERNET)
China Public Computer Internet (referred to as the CHINANET)
national public communication network (hereinafter referred to CHINAGBN, also known as the Golden Bridge Network)
the first two to education, scientific research purposes, are non-profit nature; the latter two are commercial network.
● abroad is the research, development and testing of new technology, next-generation broadband Internet, is academic as Internet2.
● Internet and the internet means the difference between:
① Internet refers specifically to the U.S. APA (ARPAnet) developed on the basis of the world's largest open computer network. Mainly uses the TCP / IP protocol communication.
② internet generally refers to the number of interconnected computer networks, the functional and logical components of a large network.
③ Internet in the Chinese translation for the Internet, and internet in the Chinese translation for the Internet. The Internet is an Internet.
2.CERNET
● CERNET (China Education and Research Network) is the China Education and Research Network demonstration project in 1994, the State Planning Commission approved 8 menstruation, presided over the implementation of the former State Education Commission.
● CERNET overall goal of building
● CERNET backbone will be built, including the national, regional networks and campus networks, including the three-level structure of the network. Figure 7-5.
● CEKNET backbone network centers built in Tsinghua University.
● my school campus under the CERNET backbone of the subnet of a Gigabit fiber, 100Mbps fiber optic connection through the central node in the northern Guangxi (Guangxi Normal University) on.
Figure 7-5
3. Internet use preliminary
(1) Internet
basic working principle of the magnitude of the Internet is bound to solve the problem of local area networks do not consider:
① lines of communication problems: LAN is usually laid by the user, Internet to join the world computer, frame by the postal service network engineering or large T company.
② communication protocol issues: LAN connection is usually the same type of computer, Internet on a wide range of computers,
Eight of China's most charming small town, would y, to consider the communication between different computers. In the Internet, the common language of communication is TCP / IP protocol.
● TCP / IP in the form: TCP (Transmission Control Protocol) and IP (Internet Protocol).
● TCP / IP works:
than the bottom of the IP protocol (specified in the structure of packets transmitted), requires a computer the information broken down into shorter packets sent. Information includes text and IP address. TCP protocol on top of IP protocols to prevent packet loss, IP packets of the inspection wrong.
(2) Internet address format on the host
① Internet number
● Internet connected with any computer, known as the host.
● host computer by a 32-bit binary number (4 bytes), with known host IP address.
● IP address is a host in the Internet network, a unique identifier, with a network IP address is not allowed to repeat.
● IP protocol version of the current IPV4 (32 bit), a new generation Ineternet2 is used in IPv6, the address length expanded to 128 bits.
Example: a host's IP address (host number) is 11001010 01100000 11000000 00100010
be divided into 4 groups of eight, separated by decimal points. General use of each set of decimal number that ranges from 0 to 255, as shown in Figure 7-6.
● 0 and 255 in the two addresses in the binary has a special purpose (for broadcast), each figure in the actual use of the range of 1 to 254.
Figure 7-6
② Internet network number on the
● IP address consists of two parts: network identifier (network number) and host identifier (the local host number), as shown in Figure 7-7.
Figure 7-7
● divided into three categories according to the scale of the network: network number representative of the type of network.
large-scale network (A class): the first digital prompt, enter the open and the server name or IP address and enter a user name and password.
(2)
the operation on the server at the ftp> prompt for FTP-related operations. (Omitted)
7.1.8 BBS (abbreviated)
7.3 computer viruses and computer virus prevention features
7.3.1
1. What is a computer virus
● computer virus (CV-Computer Viruses) is the destruction of computer functions, programs and data, and can affect self-replicating computer using a set of computer instructions (man-made special small program code).
● computer virus invasion by non-authorized data hidden in the computer system resources.
● create computer virus is both a computer expert who is hateful criminals.
2. The characteristics of computer viruses
(1) computer virus mainly consists of three modules:
● virus installed module (provide potential mechanisms)
● virus module (provided regeneration mechanism)
● virus excitation module (for excitation)
(2) the characteristics of computer viruses:
● infectious
● hidden
● latent
● can be devastating
stimulating
● 7.3.2 Classification of Computer Viruses
1. According to the nature of the dangers of computer viruses by
(1) benign virus
(2) vicious virus
2. According to the way the computer system by viruses
(1) source virus (invasion of high-level language source code)
(2) invasion of the virus (invasion of the target program)
(3) operating system, virus (invasion of the operating system to obtain control of the system)
(4) shell virus (although not with the invasion process itself but can be activated to run the program)
3. According to mode of transmission of computer viruses by
(1) disk boot sector virus infection (boot virus)
(2) transmission of the virus executable program (file virus)
7.3.3 computer virus Control
1. The spread of computer viruses channels
(1) by a floppy disk or removable disk (such as U disk) infection
(2) through the machine (hard disk) infection
(3) transmitted through the network
2. Computer Virus Symptoms
mainly as:
● screen display abnormal
● abnormal
● machines boot much slower speed
● often crashes or restarts unexpectedly phenomenon
● file contents of a file is accidentally deleted or tampered
● hidden files that do not know the source of the file size
● changes in the important area
● damaged disk cause the system to use the Chinese characters display abnormal
● Exception
● machine unusual sounds
3. Measures to guard against computer viruses
● Do not use the procedures of unknown origin, external data and programs must be carried out virus checks.
● Avoid all kinds of game software into the computer system
● not at liberty to open unknown e-mail
● software should be added to the system write protection
● use the network should have antivirus firewall systems
● regular procedures of the system, virus checking
● backup of important data in order to reduce losses
4. Computer anti-virus technology
(1) anti-virus computer hardware technology
mainly anti-virus card.
(2) anti-virus software technology
● General Tools software: easy operation, low efficiency.
● special anti-virus tools: KV3000, Rising, Kingsoft Internet Security and so on.
5. frequently used anti-virus software
7.4 computer information security computer information security knowledge
7.4.1
the importance of information security in the information age is critical, mainly in the following areas:
1. Easy to share resources in people, but also brought information security risks. Therefore it is necessary to take effective at the macro level information management, but also at the micro address information security and confidentiality of the technical problems.
2. of computer information security the main factor
(1) computer information system security of the three features:
● confidentiality (to prevent unauthorized disclosure)
● integrity (to prevent unauthorized modification )
● availability (to prevent unauthorized access)
(2) the vulnerability of computer information systems mainly in three areas: hardware, software, data.
3. computer-related crime constitutes a direct hazard to information security
computer crime has become an international problem, causing serious harm to society. Mainly in the form of computer crime:
● hacking information systems, theft of trade secrets important;
● intentional attacks against information systems, such as spreading viruses or destroy data;
● illegal copying, publication and dissemination of illegal works;
● unauthorized access to information systems, system resources, or unauthorized modification of data.
7.4.2
computer information security computer information technology security technology at two levels: first level computer system security, and the second level of data security for the computer.
1. computer information system of the computer information system security technology
system security technology is divided into two parts: the physical security and network security technology.
(1) Physical security Physical security technology technology
measures are usually taken:
● Natural Disaster Reduction, the destruction of computer hardware and software;
● reduce the external environment on the computer system for adverse effects;
● computer systems to reduce information leakage caused by electromagnetic radiation;
● reduction of non-authorized users to access and use of computer systems, etc.;
(2) network security technology
● network security technology is the computer information the basis of security technology.
● present several representative network security technologies and protocols: firewalls (Firwall) technology, Kerberos technology and SSL / SHTTP technology.
① Firewall (Firwall) technology
● is now the most widely used network security technologies.
● it is in the protected network and external networks to set a separation between the equipment for a geographically concentrated network provides the ability to resist external invasion, as shown in Figure 7-24.
Figure 7-24
● firewall typically achieved in two ways: one is installed on a dual-port host system, connecting the internal network; one is installed in a public subnet.
● firewall structure of the core part by the filters and gateways.
● firewall both hardware and also software technology and communication protocols.
② Kerberos technology
both users (sender and prepared to receive side) to test the authentication method (security agreement).
③ SSL / SHTTP technology
● SHTTP used to maintain communication with the Web server security;
● SSL is a TCP / IP communication protocol on the security protocol.
④ network security protocol features:
● identify the user and authentication (password, fingerprint, etc.)
● access control (permission set)
● data integrity (anti-illegal write data association, etc.)
● encryption (cryptography)
● Anti denied (sending and receiving parties must be sure)
● audit (log tracking)
● fault-tolerant (mirrored mode)
2. Computer Information system of data security technologies
● encrypt the data is to ensure the most effective method of data security.
● information security in computer systems, cryptography is mainly used for data encryption, but also used in communications confidential.
● cryptography, data security embodies the three elements: confidentiality, integrity and availability.
● cryptography has experienced two stages: stage one is a classic cryptography; the other is the stage of modern cryptography.
● cryptography to form two types of cryptography: the traditional cryptography and public key cryptography.
7.4.3 computer information security regulations
1. For computer information system security regulations
● 1994, the State Council promulgated the promulgated the issued the international networking entrance channel management approach , June 1, 1991 implementation of the Assembly Standing Committee on the decision to punish the crime of copyright
we only accept posts and threads in English
went to
Linear Mode
