IB Computer Science Topic A2.1: Network Fundamentals Key Definitions

The application layer provides the interface between applications and the network.

Cloud computing delivers processing power, storage and applications as an on demand service from a provider's data centre, so an organisation rents capacity over a network instead of buying and maintaining its own hardware.

A distributed system is a set of independent computers, called nodes, that cooperate on a single task while appearing to the user as one system. Because the work and the data are replicated across nodes, the system keeps running when an individual node fails.

Dynamic Host Configuration Protocol (DHCP) automatically assigns IP addresses and network configuration settings to devices on a network.

Edge computing processes data on or beside the device that produced it, rather than sending it to a central data centre first. Removing that round trip is what allows a response in milliseconds.

Firewalls are security devices that monitor and control network traffic based on predetermined rules. They act as a barrier between trusted and untrusted networks.

Gateways are network devices that act as bridges between two networks using different protocols. They translate data formats and ensure seamless communication between disparate systems.

Hypertext Transfer Protocol (HTTP) is the foundational protocol for data communication on the World Wide Web.

The internet layer handles packetization, addressing, and routing.

A LAN connects devices over a short distance, typically within a building or campus.

A mobile network is a wireless wide area network that divides its coverage area into cells, each served by a base station. As a user moves, the connection is handed from one cell to the next so the session is not dropped.

Modems (Modulator-Demodulators) convert digital data from a computer into analog signals for transmission over telephone lines or broadband connections.

The network interface layer deals with the physical transmission of data.

NICs are hardware components that enable a device to connect to a network. They convert electrical signals into digital data and vice versa.

A PAN is designed for personal use, typically within 10 meters.

Routers are devices that direct data packets between networks. They determine the optimal path for data transmission using routing protocols and routing tables.

Switches connect devices within a Local Area Network (LAN). They manage the flow of data by forwarding packets to the correct destination based on MAC addresses.

The internet is the global network of interconnected networks that communicate using the TCP/IP protocol family, giving every connected host a unique address. It is the infrastructure that services such as the worldwide web, email and streaming are built on.

Transmission Control Protocol (TCP) is a connection-oriented protocol that ensures reliable and ordered delivery of data between devices on a network.

The transport layer ensures reliable communication between hosts.

User Datagram Protocol (UDP) is a connectionless protocol that provides faster but less reliable data transmission compared to TCP.

A VPN extends a private network across a public network, such as the internet.

WAPs extend a wired network by providing wireless connectivity. They convert wired Ethernet data into wireless signals and vice versa.

A WAN connects devices across large geographic areas, such as cities or countries.