Hello all, I am a little confused about subnetting. I read an article in the linux journal. I later bought a book and it seems to give quite a different picture of subnets.
First a quote from the book: Debian GNU/Linux 2.1 Unleashed ----snip----- When subnetting, it's important to note that the subnetworks that have the address with all zeros and all ones are invalid. So, in the previous example where we divided the 8-bit host address into a 3-bit subnet address and 5-bit subnet address, we will only be able to have 6 subnetworks instead of the 8 that we might have expected because '000' and '111' are invalid subnetwork addresses... Table 16.2 Subnets inside a Class C Network Netmask Usable Subnets Hosts per Subnet Total Hosts 255.255.255.0 1 254 254 255.255.255.128 0 127 0 255.255.255.192 2 62 124 255.255.255.224 6 30 180 255.255.255.240 14 14 196 255.255.255.248 30 6 180 255.255.255.252 62 2 124 255.255.255.254 127 0 0 ----snip----- As far as I understood the following is correct. Netmask Usable Subnets Hosts per Subnet Total Hosts 255.255.255.128 2 126 252 255.255.255.192 4 62 248 255.255.255.224 8 32 240 255.255.255.240 16 14 224 255.255.255.248 32 6 192 255.255.255.252 64 2 128 I haven't needed to worry about such matters in practice, but I wanted to know which is correct. t:irvine
