2 CommunicationAS Level

2.1 Networks including the internet

15 of 15 objectives have lessons · 0 studied · 0 secure

Lessons

Why network? LANs and WANsWhy devices are connected into networks, what that gains (and costs), and how a LAN differs from a WAN. 5 min, not started
Client-server and peer-to-peerThe roles of computers in client-server and peer-to-peer networks, the benefits and drawbacks of each, and how to justify a choice. 5 min, not started
Thin clients and thick clientsWhat makes a client thin or thick, where the processing and storage happen, and how to choose between them. 4 min, not started
Cloud computing: public and privateWhat cloud computing is, how public and private clouds differ, and the benefits and drawbacks of using the cloud. 5 min, not started
Bus and star topologiesHow packets travel between two hosts in a bus and in a star network, and when each topology is the right choice. 5 min, not started
Mesh and hybrid topologiesHow packets find a route through a mesh, why mesh networks survive failures, what a hybrid topology is, and when to use each. 5 min, not started
Wired and wireless: cables, waves and satellitesThe characteristics of copper cable, fibre-optic cable, radio waves, microwaves and satellites, and the implications of choosing wired or wireless. 5 min, not started
The hardware that builds a LANWhat a switch, server, NIC, WNIC, wireless access point, cables, bridge and repeater each do in a local area network. 5 min, not started
Ethernet and CSMA/CDWhat Ethernet is, why devices sharing a cable collide, and how CSMA/CD detects collisions and stops them happening again. 5 min, not started
Leaving the LAN: routers, modems and linesThe role and function of a router, and the hardware that carries data to and across the internet, including modems, the PSTN, dedicated lines and the cell phone network. 5 min, not started
IP addresses: IPv4 and IPv6The format of IPv4 and IPv6 addresses, how to shorten an IPv6 address, and how IP addresses get packets across the internet. 5 min, not started
Subnetting and subnet masksWhy networks are split into subnets, how a subnet mask separates the network ID from the host ID, and how a device decides whether a destination is local. 5 min, not started
Public, private, static and dynamic IP addressesThe difference between public and private IP addresses and what it means for security, static versus dynamic addresses, and how a device gets its address. 5 min, not started
The web, URLs and DNSHow the World Wide Web differs from the internet, what each part of a URL does, and how the Domain Name Service turns a domain name into an IP address. 5 min, not started
Bit streaming: real-time and on-demandHow bit streaming and buffering work, how real-time and on-demand streaming differ, and why the bit rate and broadband speed matter. 5 min, not started

Syllabus objectives

15 objectives

What Cambridge says you should be able to do, in our words. Codes are the topic number plus the objective’s position.

2.1.1

Understand the purpose and benefits of networking devices.

Taught in: Why network? LANs and WANs · 3 questions

2.1.2

Understand the characteristics of a LAN (local area network) and a WAN (wide area network).

Taught in: Why network? LANs and WANs · 4 questions

2.1.3

Explain the client-server and peer-to-peer models of networked computers.

The roles of the different computers within the network and subnetwork models. The benefits and drawbacks of each model. Justify the use of a model for a given situation.

Taught in: Client-server and peer-to-peer · 5 questions

2.1.4

Understand thin-client and thick-client, and the differences between them.

Taught in: Thin clients and thick clients · 5 questions

2.1.5

Understand the bus, star, mesh and hybrid topologies.

Understand how packets are transmitted between two hosts in a given topology. Justify the use of a topology for a given situation.

Taught in: Bus and star topologies, Mesh and hybrid topologies · 12 questions

2.1.6

Understand cloud computing.

Including the use of public and private clouds, and the benefits and drawbacks of cloud computing.

Taught in: Cloud computing: public and private · 6 questions

2.1.7

Understand the differences between wireless and wired networks and the implications of using each.

Describe the characteristics of copper cable, fibre-optic cable, radio waves (including WiFi), microwaves and satellites.

Taught in: Wired and wireless: cables, waves and satellites · 6 questions

2.1.8

Describe the hardware used to support a LAN.

Including switch, server, Network Interface Card (NIC), Wireless Network Interface Card (WNIC), Wireless Access Points (WAP), cables, bridge and repeater.

Taught in: The hardware that builds a LAN · 6 questions

2.1.9

Describe the role and function of a router in a network.

Taught in: Leaving the LAN: routers, modems and lines · 3 questions

2.1.10

Understand Ethernet and how collisions are detected and avoided.

Including Carrier Sense Multiple Access / Collision Detection (CSMA / CD).

Taught in: Ethernet and CSMA/CD · 6 questions

2.1.11

Understand bit streaming.

Methods of bit streaming: real-time and on-demand. The importance of bit rates / broadband speed for bit streaming.

Taught in: Bit streaming: real-time and on-demand · 6 questions

2.1.12

Understand the differences between the World Wide Web (WWW) and the internet.

Taught in: The web, URLs and DNS · 3 questions

2.1.13

Describe the hardware used to support the internet.

Including modems, PSTN (Public Switched Telephone Network), dedicated lines and the cell phone network.

Taught in: Leaving the LAN: routers, modems and lines · 3 questions

2.1.14

Explain how IP addresses are used in the transmission of data over the internet.

Including: the format of an IP address, including IPv4 and IPv6; the use of subnetting in a network; how an IP address is associated with a device on a network; the difference between a public IP address and a private IP address, and the implications for security; the difference between a static IP address and a dynamic IP address.

Taught in: IP addresses: IPv4 and IPv6, Public, private, static and dynamic IP addresses, Subnetting and subnet masks · 18 questions

2.1.15

Explain how a Uniform Resource Locator (URL) is used to locate a resource on the World Wide Web (WWW), and the role of the Domain Name Service (DNS).

Taught in: The web, URLs and DNS · 5 questions