Edexcel GCSE Computer Science, Topic 4: Networks
Exam Questions And Answers Already Passed
LAN - local area network
A network of computers within the same building, such as a school, home or business.
It is not necessarily connected to the internet.
WAN - wide area network
When LANs are connected. Can connect organisations based in different geographical
places. The internet is an example of this.
Network topologies: bus
Each computer and network device are connected to a single cable or backbone
Network topologies: star
Each device on the network has its own cable that connects to a switch or hub. A hub
sends every packet of data to every device
Network topologies: mesh
All of the devices on the network are interconnected with one another.
Network topologies: ring
Each device (eg workstation, server, printer) is connected in a ring so each one is
connected to two other devices
MAC (media access control) address
Each unique piece of hardware on a network has this type of address. Ensures that
data is directed to the correct computer.
Data packets
A piece of information sent over a network. Messages have to be broken down before
they are transferred.
Server
A computer that holds data to be shared with other computers. A web server stores and
shares websites.
, WWW
All the interlinked HTML pages that can be accessed over the Internet
The internet
Global communication network that allows computers to connect and exchange
information
Internet Service Provider (ISP)
Organisation that provides access to the internet
Router
Connects different networks together. Read address information and forward the
messages to the correct network. Used to transfer data between a home network and
the internet.
Firewall
Network security system that checks incoming and outgoing data, deciding to allow or
disallow the data from entering or leaving the network
Hacking
The act of gaining unauthorised access to a computer system and its data
Malware
Malicious software - intended to harm or disrupt a computer system
Denial of service (DoS)
An attack that stops users accessing a network
USB - Universal Serial Bus
Socket found on modern computers, allows access for memory sticks, etc
Protocols
Networks rely on these sets of rules to allow different devices to communicate with each
other
URL - Uniform Resource Locator
Each web page address on a network is written in this form
IP address
A number that uniquely identifies each computer or device connected to the Internet.
Application Layer
Exam Questions And Answers Already Passed
LAN - local area network
A network of computers within the same building, such as a school, home or business.
It is not necessarily connected to the internet.
WAN - wide area network
When LANs are connected. Can connect organisations based in different geographical
places. The internet is an example of this.
Network topologies: bus
Each computer and network device are connected to a single cable or backbone
Network topologies: star
Each device on the network has its own cable that connects to a switch or hub. A hub
sends every packet of data to every device
Network topologies: mesh
All of the devices on the network are interconnected with one another.
Network topologies: ring
Each device (eg workstation, server, printer) is connected in a ring so each one is
connected to two other devices
MAC (media access control) address
Each unique piece of hardware on a network has this type of address. Ensures that
data is directed to the correct computer.
Data packets
A piece of information sent over a network. Messages have to be broken down before
they are transferred.
Server
A computer that holds data to be shared with other computers. A web server stores and
shares websites.
, WWW
All the interlinked HTML pages that can be accessed over the Internet
The internet
Global communication network that allows computers to connect and exchange
information
Internet Service Provider (ISP)
Organisation that provides access to the internet
Router
Connects different networks together. Read address information and forward the
messages to the correct network. Used to transfer data between a home network and
the internet.
Firewall
Network security system that checks incoming and outgoing data, deciding to allow or
disallow the data from entering or leaving the network
Hacking
The act of gaining unauthorised access to a computer system and its data
Malware
Malicious software - intended to harm or disrupt a computer system
Denial of service (DoS)
An attack that stops users accessing a network
USB - Universal Serial Bus
Socket found on modern computers, allows access for memory sticks, etc
Protocols
Networks rely on these sets of rules to allow different devices to communicate with each
other
URL - Uniform Resource Locator
Each web page address on a network is written in this form
IP address
A number that uniquely identifies each computer or device connected to the Internet.
Application Layer
