What are IP and MAC addresses, what does DNS do, and how is data routed across the internet?
IP addresses and MAC addresses, the purpose of the Domain Name System (DNS), and how data is routed across the internet.
A focused answer to the WJEC GCSE Computer Science Unit 1 content on internet addressing and routing, covering the difference between IP addresses and MAC addresses, the purpose of the Domain Name System (DNS), how routers direct data across the internet, and how the internet links networks together worldwide.
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What this topic is asking
WJEC wants you to know the difference between IP and MAC addresses, the purpose of the Domain Name System (DNS), and how data is routed across the internet. This is part of the Communication content in Unit 1 of WJEC GCSE Computer Science (3500).
IP addresses and MAC addresses
The Domain Name System
Routing across the internet
The internet
Try this
Q1. State one difference between an IP address and a MAC address. [1 mark]
- Cue. A MAC address is unique and permanent (tied to the hardware); an IP address can change depending on the network.
Q2. State what the DNS translates a domain name into. [1 mark]
- Cue. An IP address.
Exam-style practice questions
Practice questions written in the style of WJEC exam questions on this dot point, with worked answer explainers. The year tag is the paper they imitate, not the source.
WJEC-style Unit 14 marksExplain the difference between an IP address and a MAC address.Show worked answer →
A Unit 1 addressing question. An IP address is a numerical address given to a device on a network, used to identify it and route data to it across networks; it can change depending on the network the device joins (1 mark for identifying on a network, 1 mark for it being assigned and able to change). A MAC address is a unique, permanent address built into a device's network interface card by the manufacturer, used to identify the device on a local network; it does not change (1 mark for unique/permanent, 1 mark for fixed to the hardware). Markers reward the routable, changeable IP address versus the fixed, hardware MAC address. A common error is to say both are permanent, or to confuse which one is used to route across the internet.
WJEC-style Unit 13 marksDescribe the purpose of the Domain Name System (DNS).Show worked answer →
A Unit 1 DNS question. The Domain Name System (DNS) translates human-friendly domain names (such as a website address typed into a browser) into the IP addresses that computers use to locate each other (1 mark for translating names to IP addresses). When a user types a web address, the browser asks a DNS server for the matching IP address (1 mark), and once it has the IP address it can connect to the correct web server (1 mark). Markers reward the name-to-IP-address translation and the use of a DNS server. A common error is to say DNS stores web pages, when it only stores the mapping from names to IP addresses.
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