On Sat, May 27, 2023 at 12:59:59AM +0000, Andy Smith wrote: > On Mon, May 22, 2023 at 08:26:47PM -0400, Dan Ritter wrote: > > No. What's the netmask if you have: > > > > IP: 192.168.255.132 > > broadcast: 192.168.255.255 ? > > It's 255.255.0.0. > > Specifying a broadcast address does completely define the network > range. If you know that 192.168.255.255 is the broadcast then the > network can only be 192.168.0.0/16.
Dan's example was carefully chosen so that this is not true. The last 16 bits of the broadcast address are all 1. This means the network part of the address could be anywhere from 16 to 31 bits. All are equally possible.
