A subnet mask in class C can have _______ 1s with the remaining bits 0s.


Class C subnet is, accordingly it has 9 1s on first byte,9 1s on second byte and 9 1s on third byte.etcSo total 27 1s but the Ans is 25


For 255 it has 8 1s on first byte,8 1s on second and 8 1s on third.=24 How 25?

Can anyone guide What I am doing wrong?


closed as off-topic by David Richerby, Evil, vonbrand, hengxin, Luke Mathieson Jan 16 '16 at 9:13

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "This question does not appear to be about computer science, within the scope defined in the help center." – David Richerby, Evil, vonbrand, hengxin, Luke Mathieson
If this question can be reworded to fit the rules in the help center, please edit the question.

  • 1
    $\begingroup$ Where do you get 9 bits 1 in an octet (8 bits)? $\endgroup$ – vonbrand Jan 15 '16 at 20:51

Check again your count of how many 1's are in the binary representation of 255. Beyond that, there's nothing wrong with your reasoning. The answer "25" is wrong.

Some examples are available in Wikipedia: https://en.wikipedia.org/wiki/Subnetwork

  • $\begingroup$ I have edited my Ans $\endgroup$ – Jason arora Jan 15 '16 at 17:08
  • $\begingroup$ Not understood .I could not relate from the link . $\endgroup$ – Jason arora Jan 15 '16 at 17:35
  • $\begingroup$ @Jasonarora, It's not clear to me what you couldn't understand, so I wouldn't know how to begin to help. I believe I answered the question that was asked. If you are having trouble understanding some aspect of the concepts of networking, I suspect you ask a new question focused on a specific conceptual issue you're uncertain about. As a rule of thumb, a good conceptual question should be useful even to someone who isn't looking at the specific problem you happen to be working on. (Caveat: This isn't the place to get someone to proof-read your homework answer.) $\endgroup$ – D.W. Jan 15 '16 at 17:48
  • $\begingroup$ Homework? Is the learning problems becomes homework.Then,I will love homework.Thanx for your guidence $\endgroup$ – Jason arora Jan 15 '16 at 17:51

Not the answer you're looking for? Browse other questions tagged or ask your own question.