ICT UNIT 4

• Encryption is the process of putting plaintext through a cipher to produce ciphertext
• Virus is a piece of programming code which can install and replicate itself onto a computer system without user's permission
• Viruses can cause issues like computer to crash, files can be deleted, files can be copied by hacker, files can be corrupted, can stop production until virus has been quarantined
• Spyware gather data from computers without user knowing, they could monitor key presses to gain personal info or passwords. can use anti-virus and anti-spyware software
• Verification is a way of making sure the data being entered into the system is exactly matching the source of data
• Cloud computing is an Internet-based computing in which large groups of remote servers are networked to allow sharing of data-processing tasks, centralised data storage and online access to computer services or resources
• ADVANTAGES OF CLOUD COMPUTING: low cost and affordable, provides high security, backup and restore data, data managed easily
• DISADVANTAGES OF CLOUD COMPUTING: sensitive data, security of data concerns, internet connectivity, limited control
• Firewall is a device or piece of software placed between your computer (LAN) and rest of network (WAN)
• LAN is a local area network and covers small area e.g. one building
• LAN consists of number of computers and devices connected to a switch that is connected to a router
• WAN is a wide area network and extend over a large geographical area
• WANs are created by joining several LANs togehter
• Routers are used to connect LANs to form WAN
• The internet is public and available to all users and network of networks and has more info than Intranet
• Intranet is within one organisation, policed, has an extra layer of security
• Intranet is used to view internal webpages, internal emails and sharing internal documents
• Data found on Intranet is more reliable than Internet
• A certificate is something that provides proof that websites are legitimate and secure
• Certification authority (CA): the people who validated websites by providing them with certificates
• Things inside certificate: issued to, issued from and validity period
• Hub sends info given in packets to all computers
• Switch sends info given in packets to specific computer as it knows MAC address
• Bridge connects LANs togehter
• Modem converts analogue to digital signals and vice versa
• Network interface card (NIC) allows a device to connect to network using device's MAC address
• Router routes data packets from network to another based on IP address
• Methods of authentication: Passwords, biometrics, magnetic swipe cards, transaction authentication number, two-factor authentication
• WLAN is a wireless LAN that uses radio signals (WiFi) to connect computers
• Access points are devices which are connected to wired network at fixed locations and provide wireless access to devices on network
• Validation is an automatic computer check to ensure that the data entered is sensible and reasonable