AQA 7517 4.9.4.4: Subnet masking
The free BugBot lesson that teach this point, a robot to try it on, and the past-paper questions that test it.
What it covers
At GCSE (F10.5) an IPv4 address was four numbers from 0 to 255, and IPv6 was the longer, hexadecimal version. At A level an IP address has a structure: part of it names the network and the rest names the host on that network. A subnet mask says where the split is, and a single bitwise AND, which you met in A7, tells a device whether another address is on its own network or must be reached through a router.
- Network and host
- Subnet masks
- IPv4 and IPv6
- Public and private addresses
Or do it in the simulator, with tasks that mark themselves
Lessons that teach it
- A12.5 IP addresses and subnets Networks and the web
Network and host identifiers, subnet masks with AND, IPv4 and IPv6, public and private addresses.
Try it on a robot
The task from A12.5 IP addresses and subnets, running here. Change the program and press Run.
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