Network Computer Science

LAN (Local Area Network)

A network covering a small geographical area, such as a single site or building, using hardware owned by the organisation.

WAN (Wide Area Network)

A network covering a large geographical area, connecting multiple LANs together using third-party telecommunications infrastructure.

Four layers of the TCP/IP model in order from top to bottom

Application Layer, Transport Layer, Internet Layer, and Link Layer.

HTTP and HTTPS

Protocols used for requesting and displaying web pages, where HTTPS provides encryption for secure data transfer.

FTP (File Transfer Protocol)

A network protocol used to transfer and manipulate files between clients and servers on a computer network.

Difference between POP3 and IMAP

POP3 downloads emails onto a local device and deletes them from the server, while IMAP syncs emails across devices by keeping them stored on the server.

Firewall

A hardware or software security system that monitors and filters incoming and outgoing network traffic according to predefined security rules.

MAC address filtering

A security measure where a network device only allows access to specified physical hardware addresses.

Star network topology

A network structure where every individual device connects directly to a central switch or hub.

IP address

A unique numerical identifier assigned to a device on a network, used to route data packets across the internet.

Ethernet

A family of wired networking protocols operating at the link layer, defining how data is formatted and transmitted over physical cables.

Wi-Fi

A family of wireless networking protocols that use radio waves to transmit data between devices within a local network.

TCP (Transmission Control Protocol)

A connection-oriented transport layer protocol that provides reliable, error-checked delivery of data packets between applications.

UDP (User Datagram Protocol)

A connectionless transport layer protocol that sends data packets without establishing a connection or guaranteeing packet delivery, allowing for faster transmission.

IP (Internet Protocol)

An internet layer protocol responsible for addressing and routing packets of data across networks so they can reach their destination.

HTTP (Hypertext Transfer Protocol)

An application layer protocol used by web browsers to request and render web pages from a web server.

HTTPS (Hypertext Transfer Protocol Secure)

An encrypted version of HTTP that uses encryption protocols like SSL/TLS to securely transmit web page data.

FTP (File Transfer Protocol)

An application layer protocol used to upload, download, and transfer files between a client and a server on a network.

SMTP (Simple Mail Transfer Protocol)

An application layer protocol used for sending email messages from a client to a mail server or between mail servers.

IMAP (Internet Message Access Protocol)

An application layer protocol used to retrieve emails from a server, synchronizing them across multiple devices without deleting them from the server.