IP Addresses · IPv4 vs IPv6 · Internet vs WWW · URLs · Hosting
CSZoneEdexcel GCSE Computer Science 1CP2
Internet vs World Wide Web
Two Different Things
The Internet: the global physical infrastructure of interconnected networks — cables, routers, servers worldwide. Carries all internet traffic including email, video calls, games.
The World Wide Web (WWW): a collection of web pages and resources linked by hyperlinks and accessed via the internet using HTTP/HTTPS. One service that runs on the internet.
Think of the internet as roads, the WWW as one type of vehicle using those roads
IP Addresses: IPv4 vs IPv6
Identifying Devices on the Internet
IPv4: 32-bit address — four groups of 0–255. e.g. 192.168.0.1. Only ~4.3 billion unique addresses — running out as the number of devices grows.
IPv6: 128-bit address — eight groups of hexadecimal. e.g. 2001:0db8:85a3::8a2e:0370:7334. ~3.4 × 10³⁸ unique addresses — solves the shortage.
Most devices use NAT (Network Address Translation) to share a single public IPv4 address among many local devices
Web hosting: websites are stored on servers maintained by hosting companies. The server is always on and connected to the internet to serve pages.
Cloud hosting: website files distributed across multiple data centres for reliability and scale — used by large sites
Exam Practice
Have a go at this question
Edexcel-style question
Explain why IPv6 was developed and give one difference between IPv4 and IPv6.
3 marks
IPv6 was developed because IPv4's 4.3 billion addresses are being exhausted due to growth in internet-connected devices [1]. IPv6 uses a 128-bit address, whereas IPv4 uses a 32-bit address [1], providing a vastly greater number of unique addresses [1].
Key Takeaways
What to Remember
Internet: global infrastructure; WWW: web pages accessed via HTTP — a service on the internet