Networks
A network is two or more computers connected together to share data
LAN: is a Local Area Network, all of the computers are in 1 location.
Components of a LAN
Network Interface Card (NIC) connects a computers to a network
Router: Connects a LAN to the internet
Hub: Sends data packets to all computers in a LAN
Advantages and disadvantages of using LAN's
Advantages: users can share data, an internet connection and peripherals.
Disadvantages: LAN's are expensive and viruses are quickly transferred between computers
WLAN’s
WLAN’s Wireless Local Area Networks: devices are connected by radio waves rather than cables
WLAN's are better than LAN's because they are cheaper to install and new devices can be added anywhere. LAN's are better than WLAN's because they are more secure and have faster transmission speeds.
WAN
WAN (Wide Area Network): computers connected together over a wide Geographical Area. The Internet is a WAN
The Internet
The internet is an international network of computers. An ISP is a company that connects your computer to the internet.
World Wide Web
The world wide web is a way of sharing connected documents using the internet. To view webpages, you need a piece of software called a browser
URL’s (Website Addresses)
Each website has a unique address (URL) e.g http://www.google.com which specfies the name of computer on the internet.
Proxy servers
Proxy servers are used to restrict websites that are available to users, they also cache (store) websites for quicker access.
Intranets
An intranet is network of computers that can only be accessed inside an organisation and which can be used to keep confidential documents secure.
Network security
A hacker is someone who attempts to gain illegal unauthorised access to a computer system. A hacker might steal data e.g. bank account details or change data held on a computer system
Authentication Methods
User ID’s and Passwords
Unique data that needs to be entered before access to a computer system is gained.
A secure password is one that is at least 8 characters and should include letters, capital letters, numbers and symbols making it hard to guess.
Firewalls
Prevent unauthorised computers from gaining access to a network, firewalls do not block users just computers
Biometric methods
Fingerprints: are used because they are unique meaning only authorised users will have access to a computer system
Swipe cards
Only allow authorised access to a network / building
Encryption
Encryption makes data unreadable by scrambling it. An encryption key is required to decrypt the data to make it readable.
Viruses
Virus: A virus is a program that copies itself and causes damage to a computer system. To reduce your risks of a virus, you should use an up to date virus scanner
Spyware
Spyware: software that logs key presses or other details on a computer e.g. bank account details
A network is two or more computers connected together to share data
LAN: is a Local Area Network, all of the computers are in 1 location.
Components of a LAN
Network Interface Card (NIC) connects a computers to a network
Router: Connects a LAN to the internet
Hub: Sends data packets to all computers in a LAN
Advantages and disadvantages of using LAN's
Advantages: users can share data, an internet connection and peripherals.
Disadvantages: LAN's are expensive and viruses are quickly transferred between computers
WLAN’s
WLAN’s Wireless Local Area Networks: devices are connected by radio waves rather than cables
WLAN's are better than LAN's because they are cheaper to install and new devices can be added anywhere. LAN's are better than WLAN's because they are more secure and have faster transmission speeds.
WAN
WAN (Wide Area Network): computers connected together over a wide Geographical Area. The Internet is a WAN
The Internet
The internet is an international network of computers. An ISP is a company that connects your computer to the internet.
World Wide Web
The world wide web is a way of sharing connected documents using the internet. To view webpages, you need a piece of software called a browser
URL’s (Website Addresses)
Each website has a unique address (URL) e.g http://www.google.com which specfies the name of computer on the internet.
Proxy servers
Proxy servers are used to restrict websites that are available to users, they also cache (store) websites for quicker access.
Intranets
An intranet is network of computers that can only be accessed inside an organisation and which can be used to keep confidential documents secure.
Network security
A hacker is someone who attempts to gain illegal unauthorised access to a computer system. A hacker might steal data e.g. bank account details or change data held on a computer system
Authentication Methods
User ID’s and Passwords
Unique data that needs to be entered before access to a computer system is gained.
A secure password is one that is at least 8 characters and should include letters, capital letters, numbers and symbols making it hard to guess.
Firewalls
Prevent unauthorised computers from gaining access to a network, firewalls do not block users just computers
Biometric methods
Fingerprints: are used because they are unique meaning only authorised users will have access to a computer system
Swipe cards
Only allow authorised access to a network / building
Encryption
Encryption makes data unreadable by scrambling it. An encryption key is required to decrypt the data to make it readable.
Viruses
Virus: A virus is a program that copies itself and causes damage to a computer system. To reduce your risks of a virus, you should use an up to date virus scanner
Spyware
Spyware: software that logs key presses or other details on a computer e.g. bank account details