What is Subnet?
A smaller network carved out of a larger IP range.
In plain English
A subnet groups devices that share the start of their IP addresses. The subnet mask, or the slash number after an address, says how many bits belong to the network part. Subnets keep traffic organised, limit how far broadcasts travel and let you apply different security rules to different groups.
Example
A /24 network such as 192.168.1.0/24 has 256 addresses, of which 254 can be given to devices because one is the network address and one is the broadcast address.
Where you will meet it
This idea belongs to the subject area of these practice tests. We do not publish or predict real exam questions.
- Cisco CCST Networking practice tests
- CompTIA Tech+ practice tests
- Cisco CCST IT Support practice tests
Related terms
- DHCP: The service that automatically gives devices an IP address and other network settings.
- DNS: The system that turns names like example.com into the IP addresses computers use.
- OSI model: A seven-layer way of describing how data travels across a network.
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