Exam-style question
Try this first
An IP address is 192.168.10.77 and its subnet mask is 255.255.255.0. What is the network identifier?.
- A.192.168.10.77
- B.192.168.10.0
- C.192.168.0.0
- D.255.255.255.0
Model answer
What a good answer should say
- 192.168.10.0
Explanation
Why this works
The mask 255.255.255.0 identifies the first three octets as the network part. The host part is replaced with zeroes to give 192.168.10.0.
Common mistake
No common mistake is linked to this question yet.