Skip to content
VirtusAcademy

Network Protocols

FoundationHigherAQA

Learn Network Protocols for GCSE Computer Science with this free worksheet and full mark scheme — Foundation and Higher exam-style questions with worked answers. Protocols are agreed rules for communication, including TCP, IP, HTTP, HTTPS, SMTP and IMAP.

Free downloads

These worksheets and mark schemes are original, written for Virtus Academy and checked against the current AQA specification. Every worksheet comes with a full mark scheme.

Foundation

WorksheetFoundation · PDFMark SchemeFoundation · PDF

Higher

WorksheetHigher · PDFMark SchemeHigher · PDF

Topic overview

A protocol is a set of rules governing how data is transmitted between devices on a network.

Without agreed rules, devices from different manufacturers could not communicate — each would format and interpret data differently. Protocols specify how data is formatted, addressed, transmitted and checked for errors.

Several must be known. TCP breaks data into packets and reassembles them at the destination. IP handles addressing and routing. HTTP transfers web pages, and HTTPS is the encrypted version. FTP transfers files. SMTP sends email, while POP and IMAP retrieve it — the difference being that POP downloads and deletes from the server, whereas IMAP leaves messages there for access from multiple devices.

Revision notes

Why protocols are needed

A protocol is a set of rules governing data transmission.

Without agreed rules, devices from different manufacturers could not communicate, because each would format and interpret data differently.

The main protocols

TCP: breaks data into packets and reassembles them. IP: addressing and routing.

HTTP: transfers web pages. HTTPS: the encrypted version of HTTP. FTP: transfers files. SMTP: sends email.

POP versus IMAP

Both retrieve email, but they differ in what happens to the message.

POP downloads the message and deletes it from the server. IMAP leaves it on the server, so it can be accessed from multiple devices and stays synchronised.

Key points

  • A protocol is a set of rules for data transmission.
  • Protocols allow different devices to communicate.
  • TCP breaks data into packets and reassembles them.
  • IP handles addressing and routing.
  • HTTPS is the encrypted version of HTTP.
  • POP deletes from the server; IMAP does not.

Worked examples

Example 1

State what is meant by a protocol. [1 mark]

Working

A set of rules governing how data is transmitted between devices on a networkdefine the term

Example 2

State the difference between POP and IMAP. [2 marks]

Working

POP downloads the email and deletes it from the serverdescribe POP
IMAP leaves the email on the server so it can be accessed from multiple devicesdescribe IMAP

Example 3

Explain why protocols are necessary on a network. [2 marks]

Working

Devices from different manufacturers must agree on how data is formatted and transmittedstate the need
otherwise each would interpret the data differently and communication would failexplain the consequence

Common mistakes

  • Confusing TCP and IP roles.

    TCP handles packets; IP handles addressing and routing.

  • Saying HTTPS is a different protocol from HTTP.

    It is HTTP with encryption added.

  • Mixing up POP and IMAP.

    POP deletes from the server; IMAP leaves the message there.

  • Naming a protocol without its purpose.

    Questions want what each one does.

Exam tips

  • Learn each protocol with its specific purpose.
  • Keep TCP and IP roles distinct.
  • Remember HTTPS is encrypted HTTP.
  • Contrast POP and IMAP by what happens on the server.

Key terms

Protocol
A set of rules governing data transmission.
TCP
The protocol breaking data into packets.
IP
The protocol handling addressing and routing.
HTTPS
The encrypted version of HTTP.

Related topics

Written and reviewed against the current AQA specification. Spotted an error? Let us know.