Computer Networks and Internet Basics

File Transfer Protocol (FTP)

• A standard protocol that allows files to be transferred over a TCP network
• Used to download programs from other servers and upload web pages to a hosting server on the internet

Internet Service Provider (ISP)

• A cost-effective gateway for people and organizations to access the internet
• Provides additional services such as email, website development, technical support, and troubleshooting
• Examples include BT, Virgin Media, and Sky

Internet Infrastructure

• A huge client-server system of interconnected computers that uses a wide range of hardware
• Servers are powerful computer hardware that connect other computers together, running on special server software to service user requirements
• Examples include file servers, printers, web servers, and email servers

Client and Server

• A client is a computer that uses the services provided by a server
• A server is a powerful computer hardware that connects other computers together, running on special server software

Router

• A piece of hardware that connects two or more networks
• Directs data packets to the correct destinations and handles data traveling to other directions

Connecting Backbone

• The main connecting data routes between large networks on the internet and smaller networks in local regions

Internet Connection Methods

• There are three methods: Wireless, Broadband, and Dial-up

Wireless

• Used by wireless devices (mobile phones) to log in to the internet
• Does not need to be fixed stationary, allowing for flexibility
• However, requires a connection, can be less secure than others, and tends to have slower data transmission speeds than wired broadband methods

Broadband

• Requires a wired connection to a broadband supplier, normally via a network card in the computer
• Allows for faster data transmission speeds than dial-up and wireless methods
• Requires a wired base, making it less flexible than wireless methods

Dial-up

• A wired connection via a telephone line, requiring a modem to convert signals to and from analogue for transmission
• Allows existing telephone circuits to be used, which is useful in some areas
• However, tends to have slower data transmission speeds than broadband and wireless methods

The Internet and World Wide Web

• The internet is a system of interconnected computers and servers
• The World Wide Web is a collection of interconnected webpages that form a website

Network

• A network consists of two or more computers that are linked together to share resources, exchange files, or allow electronic communications

ISP Key Terms

Point of Presence (POP)

• An access point of the internet, containing all the hardware that allows internet users to access the internet
• An ISP may operate several POPs in their area to allow good access to the internet

Network Access Point (NAP)

• An interchange between networks within the internet
• A group of computers connected together by satellites that send information to computers, allowing ISPs to interconnect with each other

Internet Protocol (IP)

• The protocol used to route packets of information across the internet
• A packet is an individual unit of data that is carried across a network, including the internet, consisting of a header and a body

Transmission Control Protocol (TCP)

• A set of standardized rules that allow computers to communicate on a network such as the internet
• Takes data from a user application program and passes it to the IP for transfer across the internet