I'm new to networks and I was watching this video on Cybrary on Subnetting. The example h explained goes like this:
Q. Subnetting 192.168.1.10/27 with subnet mask 255.255.255.0
- He said 24 bits are for network address and 8 for the host (understood)
- He said that he'll be using 3 bits (the 3 most significant bits out of 8 bits of host address) and he used this formula : 2n which is equal to the number of subnets (he put n = 3)
- He said that 5 bits are unused and he used: 2n - 2 (plugged n = 5) which is equal to the number of hosts in each subnet.
- In the end he had 8 subnets each having 30 hosts which makes a total of 240 IP addresses + 8 broadcast + 8 network
I lost him after point 1. I didn't really understand why he said he'll be using 3 bits. Is it because the network is subnetted by a number (27) more than 16 and less than 32? So if it was subnetted by 50 he would have used the 2 most significant bits and left 6 unused bits? I would then have 4 subnets each having 62 hosts making a total of 248 IP addresses + 4 network + 4 broadcast.
Am I correct in the way I understood this?