Communication and Network

Modulation

 Modulation is a process that causes a shift in the range of frequencies in a signal where it converts the message signal from digital to analog. It enabled the signal to transport the information that it carried in the signal to some destination.  It can be applied to direct current to alternating current and to optical signal. 

Demodulation

 

It is the extracting of the information from the modulated waves in which an output wave or signal is obtained by having the characteristics of the original waves. It is the process of converting from analog to digital. 

Bandwidth

It is to calculate the capability of the communication channel where how much information can move across the communication channel in a given amount of time.

TCP/IP

Transmission control protocol/Internet protocol, in short TCP/IP,  it is a communication protocols that is connect to the host using the internet. It has 2 features that involve identifying sending and receive device, and breaking information into small parts to transmit across the internet.

Node

 Node is an active device that is connect to a network. Every node has a unique network address, sometimes called a Data Link Control (DIC) adress or Media Access Control (MAC) address.

Client

A client is an application or system that accesses a remote service on another computer system, known as a server, by way of a network in which it applied to devices that were not capable of running their own stand-alone programs, but could interact with remote computers via a network.

Server

A server which sometimes called an enterprise server, is a computer system that provides essential services across a network, to private users inside a large organization or to public users in the internet. it is usually large in size.

Network Operating System

 

Network Operating System in short NOS is to control the activity in the internet from all the computer. It is usually for sharing information and resources in communication form one computer to another.

Network Administrator

The Administrator is the USER (or group of users) who has control over how the others users (network clients) access and use the network resources. Network administrators manage the use of resources and services used on the network.

Secondary Storage

Disk Caching

Disk Caching is a mechanism for improving the time it takes to read from or write to a hard disk. It improves hard-disk performances by anticipating data needs.  It also provides a temporary high-speed holding area between a secondary storage device and the CPU.

File Compression

File compression is not limited to hard-disk system and it is frequently used to compress files or floppy disks. It helps to speed up transmission of files from one computer to another. It scan files for ways to reduce the amount of required storage.

File Decompression

Data compression is where it is the opposite if file compression that expand compressed files. Decompression of file archives can be achieved on all computers, but live decompression of video requires much more powerful hardware.

Internet Hard Drive

Internet Hard Drive is a special service site on the Web that provide users with storage. It is in low cost and it is flexible to access information from any location using the Internet. Internet hard drive will allow you to "deposit" your computer files into a remote hard drive, and then later access those very same files from any other computer.

Optical Disc Drive

Optical disc drive (ODD) is a disk drive that uses laser light or electromagnetic waves near the light spectrum as part of the process of reading or writing data to or from optical discs. 1s and 0s are represented by pits and lands.

Solid-state storage

Solid-state storage is a nonvolatile device that have no moving parts and are more reliable and required less power than hard disks. Data  and information are stored and retrieved electronically directly from these devices much as they would be from conventional computer memory.

Input and Output

Ergonomic Keyboard

The Ergonomic keyboard is designed specifically to reduce muscles strain that is connected with repetitive movement of typing. The keyboard arrangement is not rectangular like the normal keyboard and this keyboard provided a palm rest.

Inkjet Printer

Inkjet printers are where it sprays inks onto the surface of a paper at high speed to produce high quality output. It also permits printing to be done in a variety of colour which makes them ideal for select special applications. They are reliable, quiet, relatively expensive and also most widely used.

Laser Printer

Laser Printer is similar to a photocopy machine but it used laser light beam to produce images with excellent letter and graphic quality. It is most expensive than inkjet printers because of the speed and the quality it produces.

Magnetic-Ink Character Recognition

Magnetic Ink Character Recognition, or MICR, is used by banks to automatically read those unusual numbers on the bottom of checks and deposit slips. Only a special purpose machine known as a reader/ sorter reads these numbers and provides input that allows banks to efficiently maintain customer account balance.Unlike bar-codes or similar technologies, however, MICR codes can be easily read by humans.

Optical - Character recognition

Optical – Character Recognition, on short OCR, is used specially for preprinted characters that can be read by a light source and changed into machine-readable code. A common OCR device is the hand held wand reader that is used in department store to read retail price tags by reflecting light on the printed character.

Optical - Mark Recognition

Optical Mark reading (OMR) is a method of entering data into a computer system. Optical Mark Readers "read" pencil or pen marks made in pre-defined positions on paper forms as responses to questions or tick list prompts. It is only used to score standardized multiple-choice tests.