Network connections

• Network protocols designed to increase security and privacy of data

  • Tunnelling
  • Secure sockets layer (SSL)
  • Transport layer security (TLS)
  • Internet protocol security (IPsec)
• Tunnelling


  A communications protocol that allows for the secure transmission of data from one network to another. It allows private data packets to be sent across a public network through a method called encapsulation.
• Secure sockets layer (SSL)


  A network protocol designed to ensure connections made between web clients, such as user devices, and web/mail servers are secure. It uses both public and private keys to encrypt data that is transmitted over the secure connection.
• Transport layer security (TLS)


  Updated version of SSL
• Internet protocol security (IPsec)

  A network protocol designed to encrypt and authenticate data packets that are sent across the internet. IPSec is also part of the tunneling VPN process.
• More network protocols


  • Internet control message protocol (ICMP)
  • Address resolution protocol (ARP)
  • Inverse address resolution protocol (InARP)
  • Dynamic host configuration protocol (DHCP)
  • Hypertext transfer protocol
  • File transfer protocol
• Internet control message protocol (ICMP)


  An error reporting protocol used to generate error messages, to transmit to the sender, when network problems cause delivery problems with data packets.
• Address resolution protocol (ARP)

  A protocol responsible for translation of an IP address into a MAC address for a device. It is necessary for use between the network layer and the data link layer of the OSI model.
• Inverse address resolution protocol (InARP)


  Performs the protocols of ARP, translating a MAC address into an IP address.
• Dynamic host configuration protocol (DHCP)


  A network management protocol used to assign IP addresses to devices on a network. It manages the assignment of the address so that the administrator doesn't do it manually.
• Hypertext transfer protocol


  Used for transferring the content of web pages across the internet, from a web server to a browser.
• File transfer protocol


  Responsible for the transfer of files between a client and a server in a network.
• More protocols


  • Simple mail transfer protocol (SMTP)
  • Post office protocol (POP)
  • Internet message access protocol (IMAP)
  • Telnet
  • Secure shell
• Simple mail transfer protocol (SMTP)


  Used to send an email from a computer to a mail server, between different mail servers.
• Post office protocol (POP)

  Used to retrieve emails from a mail server. When the user checks their inbox the mail is sent from the server to their device and the protocol then deletes the email from the server.
• Internet message access protocol (IMAP)

  Same as POP but the email is not deleted from the server by the protocol, the user chooses to delete it.
• Telnet


  A protocol that allows a user to connect remotely to another computer using the internet.
• Secure shell


  Provides a secure way to access a computer over an unsecure network. It is done using strong authentication and encryption methods for communication.
• BitTorrent


  A communications protocol often used in peer to peer file sharing. It allows for the transmission of large files such as videos by distributing the load of downloading the file across several sources on the network. The several sources are collated to create a swarm, with each host given pieces of the file. This protocol allows the user to join the swarm and download the file from the available hosts simultaneously. The protocol can rearrange the pieces to create a complete file, with each piece protected so that it isn't modified.