DGB 2: Networks and Internet Communication

← Digital Literacy – Year 2

Networks do not transfer information as one single block. They use defined procedures between many devices. A useful basic model is that data is divided into packets, packets contain addressing information, routers forward them through networks, and the destination processes or reassembles the data.

Curriculum reference

Area	Classification
Competence area	Information
Perspectives	Technical perspective (T)
Focus	Networks and internet communication
Competence	Model the transmission of information in networks using data packets, addresses, routers and routes and apply the model to common internet services.

Learning objectives

Students can:

explain a network as a connection between several digital devices;
distinguish a local network from the internet;
describe data packets as parts of a transmission;
distinguish sender, receiver and payload in a simplified packet model;
explain routers as forwarding points between networks;
show that packets may take different routes;
explain why order, completeness and error checking matter;
classify streaming, chat and web access as network communication;
describe packet loss and delay as possible transmission problems;
distinguish physical transmission paths from logical communication;
create simple process diagrams using correct technical terms.

Learning content

From a device to a network

A network connects devices so they can exchange data and use shared services. At home, a router may connect notebooks, smartphones, printers and other devices to a local network and the internet. A local network can work without internet access; internet access connects it to many other networks.

Data packets

Large messages and files can be divided into smaller pieces for transmission. In a simplified packet model, each packet contains useful data plus information that helps the network deliver it. The exact real-world structure is more complex, but the model makes transmission understandable.

Addresses and forwarding

To deliver data, networks need addressing. Routers examine addressing information and forward packets towards their destination. They do not need to understand the meaning of the message itself in order to pass the packet on.

Order and completeness

Packets may not always arrive in the same order in which they were sent. Communication systems therefore need mechanisms to identify data and, depending on the protocol, check completeness or recover from missing parts. This explains why numbering pieces in a classroom model is useful.

Packet loss and delay

Packets can be delayed or lost because of congestion, poor wireless connections or other problems. Different applications react differently: a file transfer may wait and resend data, while a live call may prefer timely delivery even if a small part is missing.

Web pages, chat and streaming

Opening a website, sending a chat message and streaming a video all use network communication, but they have different requirements. Web pages involve requests and responses, chat prioritises timely delivery, and streaming continually transfers media data while playback continues.

Models and reality

Classroom packet models simplify real network protocols. Their purpose is to explain key ideas such as splitting, addressing, forwarding, delay and reassembly. A good model should be useful without being mistaken for a complete description of the internet.

Classroom activities

Represent packets in a role-play

Send numbered message cards from sender to receiver through student ‘routers’.

Expected outcome: A working packet model.

Split and transfer a message

Divide a message into pieces, shuffle them and reconstruct it at the destination.

Expected outcome: Understanding of sequence and reassembly.

Compare network routes

Send different packets through different routes and discuss why networks may not use one fixed path.

Expected outcome: A route diagram.

Model errors and packet loss

Remove or delay one packet and discuss how the receiver notices the problem.

Expected outcome: Understanding of loss and delay.

Explain web-page loading with packets

Represent a simple request and several returned resources as packet transfers.

Expected outcome: A network-level explanation of a page load.

Compare streaming and chat

Identify what delay or missing data would mean for each service.

Expected outcome: Application-specific reasoning.

Secure the vocabulary with diagrams

Label sender, receiver, packet, payload, address, router and route on a diagram.

Expected outcome: Correct technical vocabulary.

Apply packet transmission to everyday examples

Choose an image upload, game message or shared file and explain its transfer using the model.

Expected outcome: Transfer of the model to practice.

Reflect on reassembly at the destination

Explain why identifiers and ordering information are useful when many pieces arrive.

Expected outcome: A clear explanation.

Create a network story

Write a short technical story of a packet travelling from one device to another.

Expected outcome: A coherent sequence using network terms.

Self-check

I can distinguish a local network from the internet.
I can describe data packets in a simplified model.
I can explain the role of a router.
I understand that packets can take different routes.
I can describe packet loss and delay.
I can apply the packet model to web, chat and streaming.