1.3.3 Networks

A single computer not connected to anything else

• users can share files • users can share peripheral devices and connections to other networks such as the internet • servers can control security, backup of data and software updates

• increased security risks to data • malware and viruses spread more easily between computers • if a server fails, the computers connected to it may no work • computers may run slower if there is lots of data travelling on the network

• a set of guidelines/conventions that govern how a task should be performed or how a product should function • a set of hardware and software specifications that allow manufacturers to create products which are compatible with each other

• standards enable different network devices regardless of their manufacturer of model to work seamlessly together .

• a set of rules to govern the transmission of data between devices [1]

• protocols ensure that all devices follow the same rules and standards [1] • so that they interpret data and signals in the same way [1]

• HTTPS (hyper text transfer protocol secure) • HTTP (hyper text transfer protocol ) • TCP (transmission control protocol • IP (internet protocol) • FTP (file transfer protocol) • SMTP (simple mail transfer protocol) • IMAP (internet messenger access protocol) • POP (post office protocol) • UDP (user diagram protocol)

• a set of rules that govern the transmission of data [1] • these rules specify how data is represented [1] • examples include character sets [1]

• a networking protocol used in the routing of packets through networks • purpose : communication over LAN/WAN

Used for webpage rendering/requests

• a version of HTTP (also used for webpage rendering/requests) but with encryption for security • used for secure transactions like online banking and shopping

• used for transmission of files over networks • provides authentication (username and password) • can manage file directories

the standard for sending email messages between servers

• The physical layout of wires and components which form the network • eg bus, mesh, star

• the way data flows around a network

• a network topology where all computers are connected to a single cable • the ends of the cable are plugged into a terminator

• cheaper to set up ( as it requires less cable) • doesn’t require any additional hardware

• if the backbone cable fails, the entire network gets disconnected • as traffic increases, performance decreases • low security as all computers on the network can see all data transmission

• uses a central switch/computer to direct the flow of data • MAC addresses identify each device

• if one cable fails, only that computer/station is affected • is more secure • no data collisions as each station/device has its own cable to the server • transmits data faster ( so better performance than bus topology)

• expensive to install due to switch and cabling • maintaining the network is difficult because if the central device goes down, network data can no longer be transmitted to any of the nodes

• every node is connected to every other node • only one node requires a connection and all the others can share this connection • most commonly found in wireless technology eg. WiFi

• no cabling costs as it is wireless • the more nodes that are installed, the faster and more reliable the network becomes • this is because if there is a break in any of the connections, traffic can be routed via another route • new nodes are automatically incorporated into the network • Faster communication since data packets don’t need to travel via a central switch