Network Protocols (OCR GCSE Computer Science): Revision Notes
📚 Revision Notes
Network Protocols
infoNote
A protocol is a set of rules that define how data is transferred over a network.
Different protocols are used for different purposes, ensuring that communication between devices is consistent and reliable. These protocols govern everything from how data is broken into packets to how secure connections are maintained between web browsers and servers.
TCP/IP (Transmission Control Protocol/Internet Protocol)
TCP/IP is a foundational protocol that governs how data is sent between devices across networks, like the Internet. It ensures that data is split into manageable packets and sent to the correct destination.
TCP (Transmission Control Protocol)
- Splits data into packets for transmission over the network.
- Ensures the packets are correctly reassembled at the destination.
- Checks that the data is correctly sent, received, and delivered in the correct order.
IP (Internet Protocol)
- Handles packet switching, meaning it routes data to its destination.
- Each packet is given an IP address of the destination, ensuring it reaches the right device.
Other Common Protocols
| Protocol | Description |
|---|---|
| HTTP (Hyper Text Transfer Protocol) | Used for accessing and communicating with web servers, and loading websites. |
| HTTPS (Hyper Text Transfer Protocol Secure) | A secure version of HTTP that encrypts data between a browser and a web server, protecting sensitive information. |
| FTP (File Transfer Protocol) | Allows for the transfer of files between a client and a server, often used for uploading or downloading large files. |
| POP (Post Office Protocol) | Used for retrieving emails from a server. Emails are downloaded and deleted from the server once accessed. |
| IMAP (Internet Message Access Protocol) | Used for retrieving emails, but emails are stored on the server until deleted. Allows access from multiple devices. |
| SMTP (Simple Mail Transfer Protocol) | Used to send emails between mail servers and to send emails from a client to a server. |
infoNote
Key Points to Remember
- A protocol is a set of rules that defines how data is transferred over a network.
- TCP/IP is the most important protocol for communication over the internet, ensuring data packets are sent and received correctly.
- Different protocols have specific purposes: HTTP and HTTPS for web browsing, FTP for file transfer, and POP, IMAP, SMTP for email communication.