Networks, topologies and network hardware

Learning objectives

Describe what marks out a LAN, a WAN, a client–server model and a peer-to-peer model, and give a situation in which each is the better choice

Compare bus, star, mesh and hybrid topologies on cabling cost, performance under heavy traffic and the effect of a single cable break or device failure

Describe the purpose of a network interface card, a switch, a router, a modem and a wireless access point, and place each one in a typical home or school network

Compare wired media (copper twisted pair, coaxial cable and fibre optic) with wireless media (radio, microwave and satellite) on bandwidth, cost, susceptibility to interference and security

Explain the purpose of an IP address and of a MAC address, distinguish public from private and static from dynamic addressing, and explain how IPv6 answers the shortage of IPv4 addresses

Describe public and private cloud computing, and evaluate the advantages and the risks for an organisation that moves its data storage off site

Distinguish a thin client from a thick client, and describe the role of a server, a wireless network interface card, a repeater and a bridge, and of the PSTN, dedicated lines and the cellular network in connecting to the internet

Explain how Ethernet uses CSMA/CD to detect collisions and to reduce the chance of repeating them, and explain the purpose of subnetting and of a subnet mask

Distinguish real-time from on-demand bit streaming, and explain why the bit rate, the broadband speed and buffering decide whether a stream plays smoothly