Communication and Internet Technologies Flashcards
Bit:
The smallest unit of data in a computer.
Bit rate:
The rate in which data is being transferred
Serial Transmission:
Uses a single wire to transfer bits of data.
Parallel Transmission:
Uses multiple wires to transfer bits of data.
Interference:
Disturbances that can occur in the signals when sending data that may corrupt it.
Simplex:
Data transmission in one direction only.
Half-Duplex:
Data transmission in two directions but not at the same time.
Full-Duplex:
Data transmission in two directions at the same time.
Asynchronous transmissions:
Data is transmitted in an agreed bit pattern
synchronous transmissions:
A continuous stream of data which is accompanied by timing signals generated by an internal clock
Universal serial bus (USB):
USB is an asynchronous serial data transmission method. When a device is plugged into a computer using one of the USB ports:
The device will be automatically detected by the computer.
If the device is recognized and known by the computer, it will load the information efficiently.
Parity Check:
A parity check is a parity bit to make sure the data has been sent accurately. The first 7 bits of the byte are the data itself and the last bit is the parity bit. It can be odd or even.
Automatic repeat request:
ARQ uses the acknowledgment to indicate data received correctly.
Checksum:
A checksum is a simple method of error detection. To see if the data has been transmitted correctly.
Echocheck:
Data is returned to the sender.
The sender compares the data sent with the data received back.
ISP: INTERNET SERVICE PROVIDER
A company which provides us access to the internet, normally for a fee. For example, Etisalat or DU.
Explain what a modem is and how it is used to transmit data?
A modem is a hardware device which converts data into a format that can be used for internet transmission so it can be transmitted from one computer to another
Explain and give examples of a browser:
A software application which is used to locate retrieve and display content on the world wide web including images web pages and videos, for example, Google Chrome, Opera, Firefox and Safari
What is a packet used for a network:
A packet is a unit of data that can be sent across a network. A packet is used to send data reliably so that data doesn’t have to be sent as a single large file
What is meant by protocol?
The protocol is a set of rules for transmitting data between electronic devices such as computers
What is meant by a web server?
A web server is where everything is stored. It can be a server software or hardware. It can contain one or more websites. It processes incoming network requests over HTTP and other protocols
What is meant by hypertext transfer protocol (HTTP)?
Hypertext transfer protocol is an application protocol for distributed, collaborative, hypermedia information system
What is meant by hypertext Mark-up language (HTML)?
hypertext Mark-up language Is standard markup language for documents designed to be displayed in a web browser. It can be assisted by Technologies like cascading style sheets.
How are cascading style sheets used on the website?
Cascading style sheets are used to format the layout of web pages. They can be used to define text styles, table sizes and other aspects a web pages
What is meant by transmission control protocol?
a standard that defines how to establish and maintain a network conversation through which application programs can exchange data.
IP address meaning and example:
The device’s network is known as its internet protocol address because without it other devices wouldn’t be able to communicate with the device.(32-bit code)
URL:
The address of the worldwide web page. Its easier to remember than IP addresses and allows personalization. For example https//www.amazon.com. (32-bit binary)
How does a MAC address operate?
A MAC address is a hardware identification number that uniquely identifies each device on a network
How is the assigning of a MAC address different to an IP address?
a MAC address uniquely identifies a device that wants to take part in a network. An IP address uniquely defines a connection of a network with an interface of a device
Which form of data do computers understand when processing images?
In the form of pixels.
What specific place in the computer memory where values are held?
The main storage is the primary memory, and data and programs are stored in secondary memory.
What is a computer that hosts a website called?
Websites are hosted, or stored, on special computers called servers.
Why is the file format used in computers?
A file format is a standard way that information is encoded for storage in a computer file. using lossless data compression.
As humans, we process Apologue data. what type of data do computers process?
Digital data
Lossy:
Data that is deemed unnecessary or redundant is removed with this compression process. The data is removed permanently so it is effectively lost. This way the size of the file is reduced. (images, audios, videos)
Lossless:
Lossless refers to a method of compression that loses no data in the process. The compressed data can be reversed to reconstruct the data file exactly how it was. ( A music file can use lossless).
Serial transmission 2:
1) used over long distances
2) Uses a single wire
3) Reduced costs as only a single wire is needed
4) Its safer
Parallel transmission 2:
1) Used over short distances
2) uses multiple wires
3) Increased costs as multiple wires are needed
4) Quicker transmission as its sent simultaneously over many wires
5) Less safe
Hacker:
A person who tries to gain unauthorized access to a computer or network.
Malware:
A software program that is designed to damage or disrupt a computer.
Virus:
A software program that is designed to corrupt a computer and the files on it.
Spyware:
A software program that collects user’s information through their internet connection.
Hacking:
Gaining unauthorized access to a computer or network
White hat hacker:
A White hat hacker exposes security issues in a network or system, but not for lawful reasons. It can be hired by an organization to test its own systems to discover any weaknesses that exist.
Black hat hacker:
A Black hat hacker is a hacker that gains access unlawfully.
Firewall:
A system that protects unauthorized access to or from a computer or network.
Browser:
A program used to access the world wide web that displays HTML files.
Packet:
A unit of data that can be sent across a network.
Cookies:
Cookies are tiny pieces of data that are downloaded by a computer when it visits a website. Cookies are stored by the computer’s browser and are accessed by the website whenever it is visited by the client.
The difference between a static IP and a dynamic IP:
A static IP address is a fixed address.
A dynamic IP address is an address that changes.
