Yr10 CT4 2 May 2024

• Forms of attack on a network


  • Malware
  • Social engineering
  • Brute-force attacks
  • Denial of service attacks
  • Data interception & theft
  • SQL injection
• Malware


  Malicious software created to cause harm to a computer system
• Issues caused by malware


  • Files being deleted, corrupted or encrypted
  • Internet connection becoming slow or unusable
  • Computer crashing or shutting down
• Types of malware


  • Virus
  • Worms
  • Trojan
  • Spyware
  • Ransomware
• Virus


  A program that can replicate itself on a user's computer and cause unwanted and unexpected events
• Worms


  Similar to viruses but spread to other drives and computers on the network
• Trojan


  Disguise themselves as legitimate software but contain malicious code in the background
• Spyware


  Software that allows a person to spy on the users' activities on their devices
• Ransomware


  A form of malware that locks your computer or device and encrypts your documents and other important files
• Social engineering


  Exploiting weaknesses in a computer system by targeting the people that use or have access to them
• Forms of social engineering


  • Fraudulent phone calls
  • Phishing
  • Pretexting
• Brute-force attack


  An attacker repeatedly trying multiple combinations of a user's password to try and gain unauthorised access
• Denial of service attack (DOS)


  An attacker repeatedly sends requests to a server to flood the server with traffic, causing it to overload the system
• Distributed denial of service attack (DDOS)


  Similar to a DOS attack but the traffic comes from multiple distributed devices in a coordinated attack on a single server/network
• Data interception & theft


  Thieves or hackers compromising usernames and passwords as well as other sensitive data
• SQL injection


  Entering an SQL command into a text box to manipulate the SQL query
• Protocol

  A set of rules that govern communication on a network
• Examples of protocols


  • TCP/IP
  • HTTP & HTTPS
  • FTP
  • POP, IMAP & SMTP
• TCP/IP


  Two protocols, Transmission Control Protocol (TCP) and Internet Protocol (IP), that combined allow communication over the internet (WAN)
• TCP


  • Responsible for making sure communication between two routers is error free
• IP


  • Responsible for making sure data is delivered to the right device on a wide area network (WAN)
• HTTP


  Hypertext Transfer Protocol that allows communication between clients and servers for website viewing
• HTTPS


  Works the same as HTTP but with an added layer of security, where all data sent and received is encrypted
• FTP


  File Transfer Protocol that allows sending and receiving files between computers
• Email protocols


  • SMTP
  • POP
  • IMAP
• SMTP


  Simple Mail Transfer Protocol that allows communication between an email sender and the email server, and between different email servers using the internet
• POP


  Post Office Protocol for downloading emails to a device from an email server, where emails are removed from the server once downloaded
• IMAP


  Internet Message Access Protocol for downloading emails to a device from an email server, where a copy is retained on the mail server
• Protocols are used to transmit data through the network and over the internet
• Network protocol


  A set of rules for communication
• Layers


  Sub parts of a more complex task
• Layers


  • Reduce the complexity of network tasks
  • Make each layer more manageable
• Example of layers


  • TCP/IP protocol uses a 4-layer model known as a 'stack'
• Advantages of layers


  • Self-contained, which makes managing, repairing and upgrading easier as each layer can be worked on independently
  • Allows focus on specific parts of a protocol without affecting other layers
  • Promotes data exchange (interoperability) between hardware and software
• Defining 'layer' in the context of network protocols


  Breaking up a complex task into more manageable sub tasks
• Advantage of using layers to construct network protocols


  • Self-contained, which allows different developers to concentrate on one aspect of the network
  • A layer can be taken out and edited without affecting other layers
  • Promotes interoperability between vendors and systems
• RAM (Random Access Memory) is primary storage that is directly connected to the CPU and holds the data and instructions that are currently in use
• RAM

  • It is volatile, which means the contents of RAM are lost when the power is turned off
  • It is read/write, which means data can be read from and written to
  • It has a much larger capacity compared to ROM
• ROM (Read Only Memory) is primary storage that holds the first instructions a computer needs to start up (Bootstrap)
• ROM

  • It is a small memory chip located on the computers motherboard
  • It is non-volatile, which means the contents of ROM are not lost when the power is turned off
  • It is read only, which means data can only be read from
  • It has a much smaller capacity compared to RAM