Chapter 1 · Computer Networks
1.7Network Protocols and Services
The rules computers follow to talk: TCP/IP, HTTP and HTTPS, FTP, and DNS, which turns website names into IP addresses.
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Full Stack Developer · AI Engineer · Reviewed 21 Oct 2026 · 3 min read
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Two people can only talk if they share a language. Computers are the same. A protocol is the shared set of rules that lets two devices understand each other. This topic covers four protocols and services you use every day: TCP/IP, HTTP, FTP and DNS.
Protocols also handle errors and make sure data is delivered. Every device in a network must follow the same protocol, or the exchange breaks down. The book's DO YOU KNOW? box puts it simply: protocols are like languages for computers.
Transmission Control Protocol and Internet Protocol (TCP/IP)
TCP/IP is the main set of rules of the Internet, and almost all networks use it. It has two partners with two different jobs.
TCP makes sure the data arrives reliably. IP deals with addresses and routing, so the data finds its way. Together they let devices communicate.
Hypertext Transfer Protocol (HTTP)
Every time you open a website, your browser asks a web server for a page. HTTP is the protocol for that conversation.
Plain HTTP does not encrypt anything. Secure websites use HTTPS, the secure version of HTTP. HTTPS scrambles the data between the browser and the server with SSL/TLS, so attackers cannot easily get your passwords, personal details or payment data.
File Transfer Protocol (FTP)
FTP is made for moving files from one computer to another.
It lets computers share files, and it can move large files. Web developers often use it. Secure versions of FTP also exist.
Domain Name System (DNS)
Computers find each other by numbers called IP addresses. People prefer names. DNS connects the two.
So you never need to remember numbers. DNS servers do the translation for you, which makes websites easy to reach. Figure 1.14 in the book shows the process: the name www.example.com(opens in a new tab) goes to DNS, the DNS servers look it up, and the answer is the address 93.184.216.34.
The book adds that DNS works behind the scenes every time a website is opened.
Practice this topic
Short questions
1.What is a network protocol?2 marks
Answer
From the book: "A network protocol is a set of rules for communication. It defines how data is formatted and transmitted. Protocols control error handling and data delivery. All devices in a network must follow the same protocol." "Examples include TCP/IP and HTTP." The book's Summary (p.17): "A network protocol is a set of rules that controls how data is sent, received, and understood between devices."
2.What is the purpose of DNS?2 marks
Answer
From the book: "DNS stands for Domain Name System. It converts website names into IP addresses. DNS makes websites easy to access (as shown in Figure 1.14). Users do not need to remember numbers. DNS servers perform this translation process."
3.What is TCP/IP?3 marks
Answer
From the book: "TCP/IP stands for Transmission Control Protocol and Internet Protocol. It is the main protocol used on the Internet. TCP ensures reliable data delivery. IP handles the addressing and routing of data. Together, TCP/IP enables communication between devices."
4.What is HTTP?2 marks
Answer
From the book: "HTTP stands for Hypertext Transfer Protocol. It is used to transfer web pages. HTTP works between a web browser and a web server. It allows users to view websites."
5.What is HTTPS? How does it protect data?3 marks
Answer
From the book: "HTTPS is the secure version of HTTP. It uses encryption to protect data transmitted between a web browser and a web server. This encryption is provided using SSL/TLS protocols, which ensure that sensitive information such as passwords, personal details, and payment data cannot be easily intercepted by attackers."
6.What is FTP?2 marks
Answer
From the book: "FTP stands for File Transfer Protocol. It is used to upload and download files. FTP allows file sharing between computers. It is commonly used by web developers. FTP can transfer large files. Secure versions of FTP are also available."
7.Explain the DNS name resolution process shown in Figure 1.14.3 marks
Answer
Figure 1.14, "DNS Name Resolution Process", shows a computer with the website name "www.example.com(opens in a new tab)". The name goes to DNS, and the DNS servers (the cloud of servers) give back the IP address "93.184.216.34". From the book: "It converts website names into IP addresses." "DNS servers perform this translation process."
Long questions
1.What are network protocols? Explain TCP/IP, HTTP, FTP, and DNS.8 marks
Answer
Cover the 1.7 opening paragraph and its four sub-headings, using the book's text:
- Network protocol (verbatim): "A network protocol is a set of rules for communication. It defines how data is formatted and transmitted. Protocols control error handling and data delivery. All devices in a network must follow the same protocol. Protocols ensure smooth data exchange." DO YOU KNOW?: "Protocols are like languages that computers use to talk to each other." Summary (p.17): "A network protocol is a set of rules that controls how data is sent, received, and understood between devices."
- TCP/IP: "TCP/IP stands for Transmission Control Protocol and Internet Protocol. It is the main protocol used on the Internet. TCP ensures reliable data delivery. IP handles the addressing and routing of data. Together, TCP/IP enables communication between devices. It is used in almost all networks."
- HTTP: "HTTP stands for Hypertext Transfer Protocol. It is used to transfer web pages. HTTP works between a web browser and a web server. It allows users to view websites." Add HTTPS: "HTTPS is the secure version of HTTP. It uses encryption to protect data transmitted between a web browser and a web server", provided "using SSL/TLS protocols".
- FTP: "FTP stands for File Transfer Protocol. It is used to upload and download files. FTP allows file sharing between computers. It is commonly used by web developers. FTP can transfer large files. Secure versions of FTP are also available."
- DNS: "DNS stands for Domain Name System. It converts website names into IP addresses." "Users do not need to remember numbers. DNS servers perform this translation process. It plays a key role in Internet use." Draw Figure 1.14 (DNS Name Resolution Process): www.example.com(opens in a new tab), DNS, servers, 93.184.216.34.
Aim for 250-350 words.
2.Explain HTTP and HTTPS. How is HTTPS different from HTTP, and what does its encryption protect?6 marks
Answer
Cover the sub-heading "Hypertext Transfer Protocol (HTTP)", using the book's text:
- HTTP (verbatim): "HTTP stands for Hypertext Transfer Protocol. It is used to transfer web pages. HTTP works between a web browser and a web server. It allows users to view websites."
- The difference: "HTTP does not encrypt data; secure websites use HTTPS instead. HTTPS is the secure version of HTTP."
- How HTTPS protects data: "It uses encryption to protect data transmitted between a web browser and a web server. This encryption is provided using SSL/TLS protocols".
- What it protects: "sensitive information such as passwords, personal details, and payment data", which "cannot be easily intercepted by attackers".
Aim for 150-200 words.
In this chapter
- 1.1Introduction to Computer Networks
- 1.2Network Architecture and Basic Concepts
- 1.3Types of Computer Networks
- 1.4Networking Devices
- 1.5Network Topologies
- 1.6Network Models and Layers
- 1.7Network Protocols and ServicesYou are here
- 1.8IP Addressing and Subnetting
- 1.9Home Network Setup and Configuration
- 1.10Wi-Fi Security and Router Configuration
- 1.11Network Diagnostic Tools and Commands
- 1.12Network Performance
- 1.13Network Load Balancing
- 1.14Network Security
- 1.15Data Backup and Recovery
- 1.16Usability and Security Tradeoffs