Calculate directed broadcast address given IP address and subnet in PowerShell

Question

My goal is to calculate the directed broadcast address when given the IP and subnet mask of a host node. I know, sounds like homework. Once I reasoned through my task and boiled it down to this, I was amused with myself. Anyway, the solution will look something like the one in this question I suppose, but I'm not a math major and my C sucks. I could do with a PowerShell (preferred) or C# example to get me going.

thanks!

Answer 1

Here is mine which uses Get-NetIPAddress from NetTCPIP and IPAddress from the System.Net:

$NetIPAddress = Get-NetIPAddress -AddressFamily IPv4 -InterfaceIndex 25
[Net.IPAddress]::new((
    (
        [Net.IPAddress]::Parse($NetIPAddress.IPAddress).Address -band
        [uint]::MaxValue -shr (32 - $NetIPAddress.PrefixLength)
    ) -bor (
        [uint]::MaxValue -shl $NetIPAddress.PrefixLength
    )
 )).IPAddressToString