Subnet Mask

Hi all!!

I have a question about subnet mask.

if the subnet mask is this:
255.255.255.0

when convert to binary form, it would be this:
11111111.11111111.11111111.00000000

My question is can the subnet mask be something like this:
11111111.11111111.00101111.00000000

Thanks!

No.
The subnet mask is there to show you which bits of the address describe the network and which bits describe the host. The network portion of the address always starts from the left hand side and continues toward the right. Then at the right-hand side, there are one or more bits dedicated to represent the host. The subnet mask has 1's in all the bit positions for the network portion of the address and 0's in the bit positions for the host portion

In other words, the 1's in a subnet mask must start on the left and be contiguous as it moves to the right (there can't be a 0 between the 1's).

HiHi!

Ooo Wow thanks for explaining!

FishnBone