KEY TERMS!!

1. Define the term – Protocol
A standard way of communicating across a network. A protocol is the "language" of the network. A method by which two dissimilar systems can communicate.

2. What are the following protocols used for? TCP/IP, http, SMTP, FTP

TCP is a protocol which runs over a network. Http is a protocol used for the internet (internet addresses). SMTP is generally used to send messages from a mail client to a mail server. File Transfer Protocol (FTP) is a network protocol used to exchange and manipulate files over a TCP computer network, such as the Internet

3. What does GUI stand for? What was used before GUI?

A graphical user interface is a type of user interface which allows people to interact with electronic devices such as computers; hand-held devices such as MP3 Players, Portable Media Players or Gaming devices; household appliances and office equipment with images rather than text commands

4. There are two methods of data transmission – serial and parallel. Explain the difference between them.

Serial transmission is the transmission of data along a single wire, whereas parallel transmission is the simultaneous transmission of a number of different binary digits by separate parallel paths.

5. Define the term “URL”. Explain the components that make up the URL.

Universal resource locator. The address of a website. The type of address (public, government, private, educational etc), the websites name.

6. In the context of data transmission, what is “error detection”?
Error detection is the ability to detect the presence of errors caused by noise or other impairments during transmission from the transmitter to the receiver. Error correction is the additional ability to reconstruct the original, error-free data.

7. Name and explain one common method of error detection.

Parity schemes; the stream of data is broken up into blocks of bits, and the number of 1 bits is counted. Then, a "parity bit" is set (or cleared) if the number of one bits is odd (or even). If the tested blocks overlap, then the parity bits can be used to isolate the error, and even correct it if the error affects a single bit: this is the principle behind the Hamming code.

THE INTERNET!

• 50 years ago the Internet was not even thought of or imagined, the basic usage for a computer was a basic database, and yet only one program can be used at once, limiting the activity progress.They had to be cooled constantly.Programming was manual work l it lead to bugs and virus’s.


• Batch processing; 1 process at a time (took a program to run, and ran yours and someone else’s and the results were printed and given to you; time sharing is a number of things going on at once)


• Time sharing, first idea to share information from one computer to another; whilst using multiple users.


• Around 1941 DARPA (defense advanced research project agency) was formed. Where they were researching how knowledge was transferred by people to computers.


• ARPANET would stop information from doubling up.


• 1966, the individuals didnt like sharing computers so they were giving their indivdual computer where they connected them to main frames, the little computer provided the information to the larger computer for the database.


• NCP (network control protocol) Transmission control protocol replaced it.
  Something to allow all the computers to share and connect with each other.


• File transfer was inspected, files where sent in smaller packets then reformed at the destination for quicker sending speed.


• Information always had a centre (larger database computer)


• Radio raves wud cause problems in atomic attacks, so they wouldn’t work anymore
  So now they use direct waves, but they don’t have long range.


• The French invented the INTER-NET A webbed connection of computers, data, etc (created a net like design).Connect the comps through gate ways.


• TCP finally merged the connections; creating the internet! (1990)
  They made a new set of rules so that it wud allow the internet to run, from a vote of majority.

The smaller computers connected to the main frame, sending signals and information to each other.