Internet Protocols (Cambridge (CIE) IGCSE ICT)

Protocols

What is a protocol?

• A protocol is a set of rules that govern communication on a network

• There are protocols for different purposes, some of them include:

  • HTTP & HTTPS

  • FTP

  • SSL & TLS

  • VoIP

  • SMTP

HTTP & HTTPS

What is HTTP & HTTPS?

• Hypertext Transfer Protocol (HTTP) allows communication between clients and servers for website viewing

• HTTP allows clients to receive data from the sever (fetching a webpage) and send data to the server (submitting a form, uploading a file)

• HTTPS works in the same way as HTTP but with an added layer of security. All data sent and received using HTTPS is encrypted

• HTTPS is used to protect sensitive information such as passwords, financial information and personal data

FTP

What is FTP?

• File Transfer Protocol (FTP) allows sending and receiving files between computers

• Uploading and downloading files to/from a web server is often completed using FTP

• FTP offers greater efficiency and support for bulk transfers and large files such as resuming interrupted transfers

• FTP clients are software applications that use the FTP protocol to make the process easier for users

SSL & TLS

What is SSL & TLS?

• Secure socket layer (SSL) is a security protocol developed to provide secure communication over the internet

• TLS is a successor to SSL and is also a security protocol used to provide secure communication over the internet

• They both use a combination of symmetric and asymmetric encryption to secure data and ensure data integrity

• SSL operates by encrypting a user's data using a public key

  • This is done by sending a digital certificate to the user’s browser

  • This contains the public key which can be used for authentication

Where is SSL used?

• SSL is used in a variety of situations where a secure connection is required, some examples of this include:

  • Online banking

  • Online shopping

  • Using cloud storage

  • Messaging

  • Social networking websites

  • Intranets/extranets