What is de jure standard?

De jure means according to law or regulations. These standards have been properly approved by the networks governing body.

Write the names of some networks governing bodies.

The names of most popular networks governing bodies are:

Ø American National Standard Institute (ANSI).

Ø The Institute of Electrical and Electronics Engineers (IEEE).

Ø The International Standards Organization (ISO)

Ø The International Telecommunications Union Telecommunication Standards Sector (ITU-T, formally CCITT.

Ø The Electronic Industries Association (EIA).

What is de facto standard?

De facto means by tradition or by facts. These standards were developed without any formal plan and came to existence because of historical developments. These standards are most commonly used by the organizations worldwide.

What is network standards?

The standards are the precise documents containing technical and physical specifications about the network being designed. Normally those standards are taken into consideration and are worldwide acceptable.

What is metropolitan area network?

A metropolitan area network (MAN) is communication network system that covers a geographical area of a single city. Usually, MAN connects more then one LANs in a city or twon and covers a smaller geographical area than a Wan. Mobile phones (cellular) system are often MANs.

What is wide area network?

A wide area network is a network system that covers a large (or wide geographical area such as different cities of country or different countries of the world.

What is ARCnet?

ARCnet stands for attached resource computer network. It is LAN protocol. It uses either twisted pair wire or coaxial cable, and the star topology with hub attached the network.

What is token passing?

The method of controlling access to the shared network cable is called token passing.

What is token ring?

A computer network in which each node is connected to two adjacent nodes or neighbors from a closed ring or loop is called ring network topology. The token ring protocol is used in thid type of network. The token ring is closely associated with IBM, which works on the concept of a ring network and a token.

Define the term token used in networking?

A token is a special electronic signal. It consists of a series of bits, which functions like a ticket. The computer with the token can transmit data over the network. Only one token exists per network.

What is CSMA/CD?

Before transmitting the data a node must find out if the cable is in use. If so the node must wait. When the cable is free, the node must begin transmitting immediately. This process is also known as CSMA/CD (carrier sense multiple access with collision detection)

What is Recycle bin?

The recycle bin is special folder of windows on the hard disk and has an icon on desktop. It contains files and folders that deleted from the hard disk. Any files and folders you deleted from the hard disk are transferred to the recycle bin. These files or folders can be restored from the recycle bin to their original location if required for use.

What is Ethernet?

Ethernet is the most commonly used protocol in LAN. It uses a high speed network cable and bus topology , so it is relatively simple and cheaper.

What is network protocol?

The rules to send and receive data through computer network are called network protocols. These rules are defined in the network software.

Router

Router is a communication device that connects two or more networks (different or similar) and transmits data to its corrects destination using the available path on the network, is called router. It stores the routing information of each node or computer on the network. It used this information to transfer data between nodes.

What is router?

Router is a communication device that connects two or more networks (different or similar) and transmits data to its corrects destination using the available path on the network, is called router. It stores the routing information of each node or computer on the network. It used this information to transfer data between nodes.

What is gateway?

A gateway is also an electronic device or system (collection of hardware and software resources) that connects two different types of networks and translates information from one to other. It enables computer or node to communicate with a computer on another different types of network.

What is bridge?

A bridge is an electronic device that connects two similar networks and controls the data flow between them. A bridge looks at the information in each packet header and forwards data that is traveling from one network to another to its destination.

What is network interface card?

A network interface card (NIC) is used to connect a computer to other computers in the local area network. It is a circuit board that is installed inside the computer’s internal expansion slots. The NIC has a socket where the network cable is connected. The most popular network interface card is Ethernet card used to connect computers in local area network.

What is local area network?

A local area network (LAN) is a type of computer network in which computers are interconnected in limited geographical area, such as network of computers in college computer laboratory or network of computers in office building etc.

Define the network?

A network (or computer network) is a way to connect computers together so that they can communicate with each other and share information.

What is information network?

Information networks are the computer networks that communicate with public telecommunication networks. In information networks, two important technologies: computing and telecommunication work together.

What is assembler?

A translator program that translates the program written in assembly language into machine code is called assembler.

What is interpreter?

A translator program that translates each instruction of source program into machine code and execute it immediately before to translate the next instruction is called interpreter.

What is complier?

The language processor that translates the complete source code (written in high level language) as a whole into machine code before execution is called complier.

Define object code?

The source code written in high level language must be translated into machine code so that the CPU can understand it. Therefore, the source code translated into machine code is called object code.

Define source code?

The program written in high level language is called the source code.

What high level language?

The programming languages that are closed to human languages (e.g like English language) are called high level languages.

What are low level language?

The programming languages that are very close to machine code (0s and 1s) are called low level languages? The examples of low level programming languages are machine language and assembly language.

What is command prompt interface?

Command prompt is also referred to as command line user interface. In this typed of user interface, the operating system provides prompt line on the computer screen. The user communicates with the computer (or operating system) by typing commands using a keyboard. The user interface provided by MS DOS operating system is an examples of command prompt.

Write the main functions performed by the operating system ?

The main functions performed by the operating system are:

1. Manage hardware resources.
2. Memory management.
3. Load and execute programs.
4. Data security.
5. Providing interface to the users.

What is operating system?

A set of programs running in the background on a computer system and providing an environment in which other programs can be executed and the computer system cab used efficiently.

What is fetch – decode – execute cycle?

The instruction of three address format used three address fields. Each address field can specify either a register or a memory address. This type instruction requires too many bits to specify three addresses.

What is three address instruction format?

The instruction of three address format used three address field. Each address field can specify either a register or a memory address. This typed of instruction requires too may bits to specify three addresses.

What is two instruction format?

The instruction of two address format used two address field. Each address field can specify either a register or a memory address. Two address instructions are the most common in commercial computers.

What is One-Address instruction format?

The instruction of one address format uses only one address field. This format of instruction used accumulator register for all data manipulations. However, for multiplication and division, there is need for register.

What is Zero-Address instruction format?

In zero address instruction format, no address is specified. A stack organized computer does not use an address field for instructions like ADD and MUL.

What are control transfer instructions?

The instructions that used to transfer the execution control from one part of the program to another during program execution are called control transfer instructions. These instructions may be used to execute a set of instructions repeated for a number of times.

What are I/O instructions?

The instructions that used to write ad read data and from I/O devices are called I/O instructions. Every CPU provides facility to users to perform operations of reading data from a peripheral device and writing data to peripheral device. For this purpose, the programmer used the input and output instructions.

What are the data transfer instructions?

The instructions that used to transfer data from one unit of computer to another during program execution are called data transfer instructions.

What is meant by instruction set?

A set of instruction that a CPU can execute to perform different operations on data are known as the instruction set of that CPU. Different types of processors have different instruction set.

What are general purpose register?

A CPU also has general purpose registers that are used along with other registers to perform arithmetic & logical operations and these registers are also used for data movement purpose inside the computer. These registers are called EAX, EBX, ECX and EDX.

What is segment register?

The segment or address register holds addresses of the memory locations that are being currently used by the CPU. It is used as base location for program instructions data and the stack. There are four segment registers named as CS, DS, ES and SS. Each has size of 02 bytes.

What is stack pointer?

A stack represents a set of memory blocks; the data is stored in and retrieved from these blocks in an order, i.e first in and last out (FILO). This stack pointer register is used to manage the stacks in memory. This register holds the value of the top of the stack.

What is MBR?

MBR stands for memory buffer register. It holds the contents of data or instruction read from, or written in memory. The CPU used this register to store data coming from the memory or going to the memory.

What is MAR?

MAR stands for memory address register. It holds the address of active memory location that is being currently accessed by the CPU. When the CPU wants to store some data in the memory or reads the data the data from the memory places the address of the required location in the MAR.

What is instruction register (IR)?

Once an instruction is fetched it is stored in the IR where this instruction decoded.

What is Program Counter?

Program counter (PC) register holds the address of the next instruction to be fetched for execution. After instruction is fetched, the value of PC is incremented by 1. thus this register always points or holds the address of next memory location from which an instruction to be fetched.

What is I/O unit?

I/O unit provided the way to communicate between processor and I/O devices such as keyboard, monitor, printer, disk drives etc. the I/O unit to write and read data directly to and from the main memory without the involvement of CPU. Without DMA, this work is done through CPU.

What is control bus?

The computer bus (or parallel lines), which is used by CPU to send different commands (or control signals) form one component to the other is called control bus.

What is address bus?

The computer bus, which is used to identity different components of a computer as well as to specify the address of different memory locations is called address bus.

What is meant by width of Data bus?

The amount of data that a bus can carry at one time form one component of computer to another is known as width of data bus.

What is data Bus?

The computer bus which used to transfer data from one component to the other, is called data bus. It consists of 32 or 64 parallel lines. A data bus of 64 lines can transfer 64 bits (or 8 bytes) of data at a time.

What is system buses?

The system buses are the part of motherboard and are used to connect main component of the computer such CPU, and main memory. The modern general purpose computers have 70-100 lines system bus.

Define byte?

A byte is a combination of 8 bits. One character takes one byte of memory. ( a character may be a letter, numeral or special character). The capacity of the memory or the storage is expressed in terms of number of bytes it can hold or store. It means amount of data and program size are also measured in bytes.

Define is bit?

The binary number 0 and 1 is called a bit (for binary digit), which is basic unit for storing data in the computer memory. Actually the main memory consists of large number of electronic switches. Each switch can have either of two states i.e on or off. The on state represents 1 and off stat represents 0.

What is EEPROM?

EEPROM stand for electrically erasable programmable read only memory. This kind of ROM can be re-written by using electrical devices. So data stored on this form of ROM chip cab easily modified.

What is EPROM?

EPROM stands for erasable programmable read only memory. It is another important from of read only memory. Like PROM is initially blank and the user or manufacture can write his own program or data by using special devices. Unlike PROM the data written in EPROM chip can be erased by using special purpose device and ultraviolet rays.

What is PROM?

PROM stands for programmable read only memory. This form of Rom is initially blanks and the user of manufacture can write his own program and data in it by using special devices. However, once the program or data is written in PROM chip, it cannot be changed or altered and it works like normal ROM chip.

What is ROM?

ROM stands for Read Only Memory. It is type of internal memory. The contents (i.e instructions and data) stored in this type of memory ca be read but new data cannot be written into it. This the reason why it is called read only memory. The manufacture of the ROM writes the data and programs permanently into it and contents of this memory cannot be changed afterwards. ROM is a non volatile memory.

What is Cache memory?

Cache memory is similar to RAM but it is extremely fast than RAM. It is normally used between RAM and CPU. Caches speeds up processing speed of the computer because CPU stores frequently used instructions and data in it.

What is SRAM?

SRAM stands for static Ram. In SRAM individual cells are made by using digital gates and each cell and hold its value without any need to refresh it frequently. It is faster than DRAM because it does not have to be refreshed with electric charge frequently and the CPU has not to wait to read & write data.

What is DRAM?

DRAM stands for Dynamic Random Access Memory. This type of memory is used in most of the computers. In order to maintain data in DRAM chip, it must be refreshed with electric charge frequently (or periodically) otherwise data stored in DRAM may be lost.

What is address of byte?

Each byte in the memory is assigned a unique number. This number is called the address of that byte.

What is main memory?

The main memory is the most important component of the computer. It is used to store data and instructions that currently I use. Sometimes, main memory is also referred to use as working area of the computer.

What is ALU?

ALU stand for Arithmetic Logic Unit. It is another important component of CPU. It performs the arithmetic and logic operations on the data.

What is the Von Neumann idea about design of computer?

In 1951 Von Neumann and his team proposed a design of a stored program computer. According to his design a sequence of instructions (called a program) and the data are stored in the memory of the computer (or machine).

Define coding phase of SDLC?

Coding is the main phase of system development process. In this phase, the actual codes of software are written. It means that actual system is produced.

Define SDLC?

A set of activities or steps that are required to develop a system (such as software) is called the system development life cycle (SDLC). It is an organized way to develop a successful system.

What is operating system?

A set of programs running in the background on a computer system and providing an environment in which other programs can be executed and the computer system cab used efficiently.

Write the main functions performed by the operating system ?

The main functions performed by the operating system are:
Manage hardware resources.
Memory management.
Load and execute programs.
Data security.
Providing interface to the users.

What is control unit?

Control unit is the most important part of the CPU. It controls all parts of the computer and coordinates all activities in the computer. The control unit also controls the execution of instructions given to the compute. It fetches the instructions and data from the memory unit. It decodes and executes the instruction one by one.

What is CPU?

CPU stand for central processing unit. It is the most important component of the computer and it is also known as processor. CPU is considered as the brain of the computer. The CPU used in personal computer or small workstation consists of a single chip called microprocessor.

What is Fax Machine?

Fax (short for facsimile, from Latin fac simile, "make similar", i.e. "make a copy") is a telecommunications technology used to transfer copies of documents, especially using affordable devices operating over the telephone network. ...

What is Ram?

RAM stands for Random Access Memory. Actually the main memory is referred to as RAM. It is important to note that the main memory of the computer is volatile and the contents of the memory are lost as soon as the electricity supply is cut-off. The CPU can write and read data to and from the Ram. So RAM is read/write memory.

Computer

What is video capture card?

Video input is used to record film and video images. For this purpose, there must be a special circuit board known as video capture card inside your computer. The video capture card converts the video signals into digital signals that a computer can use.

What is audio board?

To enter sound signals inside the computer, a computer must have a sound card. It is a special circuit board also known as audio board.

What is video input device?

Video input device is used to record films and video images. VCR and video camera are examples of video input devices. For this purpose, there must be a special circuit board known as video capture card inside your computer.

What is audio input device?

An audio input device enters analog signals of sound and translates it to digital from store into computer for further processing. The main purpose of audio input device is to provide digital input for multimedia computers. Microphone is mostly used as an audio input device.

Define dedicated fax machine?

Dedicated fax machine is an independent normal fax machine, which can send receive information to and from the other fax machine.

What is smart card?

Smart card looks like a credit card or ATM card it contains a thin microprocessor and memory chip that embedded in it. When this card inserted into card reader (a device used to read the card), it exchanges data with the corresponding information on central computer. It can store and update some basic information also. A mobile SIM card and an ATM card are examples of smart cards.

What is magnetic stripe card?

A magnetic stripe card has stripe of magnetically encoded information on its back. Usually, the magnetic strip cards used for personal identification during driving, in the departmental stores, at public places etc.

What is magnetic stripe card?

A magnetic stripe card has stripe of magnetically encoded information on its back. Usually, the magnetic strip cards used for personal identification during driving, in the departmental stores, at public places etc.

What is bar code UPC?

Bar code is a unique identification code in the form of light and dark vertical lines (or vertical zebra-stripped marks) or bars with spaces between them of different widths. It is printed on most of the manufactured products. Actually, the name of products, its price and other descriptions are coded as bar codes. There are several bar coding schemes or systems. The most popular and commonly used bar code is UPC (Universal Product Code).

What is touch pad?

Touch pad is a pointing input device. Touch pad is also known as track pad. It is also stationary device like trackball but it has no moving parts. It is a small flat surface (or sensitive pad) over which we slide our fingertip to move the pointer on the flat surface of touch pad, the pointer (or cursor) moves on the screen.

What is touch pad?

Touch pad is a pointing input device. Touch pad is also known as track pad. It is also stationary device like trackball but it has no moving parts. It is a small flat surface (or sensitive pad) over which we slide our fingertip to move the pointer on the flat surface of touch pad, the pointer (or cursor) moves on the screen.

What is trackball?

A trackball is also a pointing input device. It performs functions like a mouse but it is a stationary device with a moveable ball on its top. The ball is rotated or rolled with finger (or plam of the hand).

What are pointing devices?

A pointing device is an input device that is used to control the movement of the pointer or cursor on the screen and to send command signals to the computer. Usually, the pointing device is used to select items on the screen, to select commands from commands menu, to draw graphs etc.

What is input device?

The devices that are used to enter data and instructions into the computer are input devices. The input device is hardware component. It accepts input (data & programs) in a form that the computer can use, and then sends to the processing unit.

Define system?

A system is a set of related components that interact with each other to perform some specific some specific task.

What is drum plotter?

Drum plotter works like a flatbed plotter. It consists of a drum or roller on which paper is placed. The drawing pens are also mounted on the drum. The drum rotates back and forth to draw (or print) the graph on the paper. Drum plotter is used to produce continuous output such as to track earthquake readings.

How laser printer prints the output on printer?

The laser printer has special drum inside it. The laser printer produces an image of the output on a drum with laser beam and magnetically charged powered ink, called toner, and then transfers the image from drum on the paper.

What is thermal printer?

Thermal printer is non impact printer. It can only print output on a special heat sensitive waxy paper. The image of the output is created on the waxy paper by burning dots on it.

What is meant by daisy wheel?

Daisy wheel printer is also an impact character printer. It has a print wheel with series of petals. This wheel is known as daisy wheel.

Define non impact printers?

The printers that produce output on paper without striking the paper are known as non impact printers. They use electrostatic, inkjet and thermal technologies for printing. Laser, inkjet and thermal printers are examples of these type printers.