COmputer Science paper 2 Flashcards
What are the four layers of the TCP/IP model?
Application Layer, Transport Layer, Internet/Network Layer, Link/Data Layer. (In order)
What does the application layer do?
Where software operates (web browsers and email services)
What does the transport layer do?
Adds IP addresses to packets then directs them between devices using routers.
What does the Internet/Network layer do?
Set up communication between 2 devices. Splits data into packets. Checks packets are sent and delivered.
What does the Link/Data Link Layer do?
Where hardware operates. Passes data over physical networks like ethernet and fibre optic cables.
What is a LAN?
A local area neatwork that covers a small geigraphical area such as a building.
What is a WAN?
A wide area network that covers a large geographical area such as the internet.
What is a PAN?
A personal area network that covers a personal area.
What is a computer network?
A group of devices connected together for the purpose of sharing resources and data.
Name 3 advantages of a computer network.
Share resources,
Share hardware,
Good value for money.
Name 3 disadvantages of a computer network.
Security can be unreliable,
Expensive to setup,
Need technical staff to maintain server.
Give 2 advantages of a star topology.
No data collisions,
If one device fails, the rest continue to work.
Give 2 disadvantages of a star topology.
Expensive due to large cable length,
If switch fails, all nodes lose network connection.
Give 2 advantages of a bus topology.
Cheaper due to less cable length,
Easy to connect a node.
Give 2 disadvantages of a bus topology.
If main cable shuts down, system shuts down,
Terminators needed at ends of backbone cable.
