JSS 3 First Term

Lesson objectives

By the end of the week, learners should be able to:

1. Recap network topologies and routing concepts from earlier terms.
2. Name internet technologies such as DNS, HTTP and TCP.
3. Describe why the World Wide Web runs as a service on the internet.
4. Trace packet journeys across routers and switches.
5. Explain latency as the sum of transmission and processing delays.

Key vocabulary

• Internet technology: named services running on the internet such as DNS and HTTP.
• DNS: the domain name system translating names to addresses.
• HTTP: the protocol transferring web pages.
• TCP: a protocol ensuring reliable delivery of packets.
• Router: a device forwarding packets between networks.
• Switch: a device forwarding frames within one network.
• Latency: the delay before a packet reaches its destination.
• Transmission delay: time spent on the physical medium.
• Processing delay: time spent handling the packet at each node.

Common misconceptions

• "DNS and HTTP are the same thing." DNS resolves names; HTTP transfers pages.
• "The web requires cables only." Wireless networks also run on radio signals.
• "Latency disappears once you reach your target." Latency returns during reassembly time.

Teacher activities

1. Starter: ask how a browser turns www.example.com into a numeric address.
2. Recap network topologies and routing briefly.
3. Name DNS, HTTP and TCP one by one with a brief purpose.
4. Model tracing a packet journey from browser to server.
5. Define latency as the sum of transmission and processing delays.
6. Close with the technology-versus-protocol distinction and exit question.

Student activities

1. Answer the starter and explain the role of DNS.
2. Name the four internet technologies and state each purpose.
3. Describe why the World Wide Web runs as a service on the internet.
4. Trace a packet journey from browser to server through routers.
5. Define latency as the sum of transmission and processing delays.
6. Answer the exit question in one sentence about DNS versus HTTP.

Practical / learning evidence

A four-technology comparison sheet, a packet-journey trace and a latency breakdown. Submit both for marking.

Resources and preparation

Printed comparison sheet, blank trace template and sample latency scenarios. Offline route: paper versions, no device needed. Display any router or switch carefully and avoid dismantling during demonstration.

Assessment for learning

Inspect the comparison sheet for four distinct technologies with purposes. Mark the packet journey for correct router and switch paths. Check the latency breakdown for sensible sums. Flag any learner who conflates DNS with HTTP.

Inclusion and homework

Provide the comparison prefilled for learners who need scaffolding and allow oral trace. Extend confident learners with five technologies and a second packet journey. Homework: name two internet technologies outside the main list and state each purpose.