function IPInRange {
    [cmdletbinding()]
    [outputtype([System.Boolean])]
    param(
        # IP Address to find.
        [parameter(Mandatory,
                   Position=0)]
        [validatescript({
            ([System.Net.IPAddress]$_).AddressFamily -eq 'InterNetwork'
        })]
        [string]
        $IPAddress,

        # Range in which to search using CIDR notation. (ippaddr/bits)
        [parameter(Mandatory,
                   Position=1)]
        [validatescript({
            $IP   = ($_ -split '/')[0]
            $Bits = ($_ -split '/')[1]

            (([System.Net.IPAddress]($IP)).AddressFamily -eq 'InterNetwork')

            if (-not($Bits)) {
                throw 'Missing CIDR notiation.'
            } elseif (-not(0..32 -contains [int]$Bits)) {
                throw 'Invalid CIDR notation. The valid bit range is 0 to 32.'
            }
        })]
        [alias('CIDR')]
        [string]
        $Range
    )

    # Split range into the address and the CIDR notation
    [String]$CIDRAddress = $Range.Split('/')[0]
    [int]$CIDRBits       = $Range.Split('/')[1]

    # Address from range and the search address are converted to Int32 and the full mask is calculated from the CIDR notation.
    [int]$BaseAddress    = [System.BitConverter]::ToInt32((([System.Net.IPAddress]::Parse($CIDRAddress)).GetAddressBytes()), 0)
    [int]$Address        = [System.BitConverter]::ToInt32(([System.Net.IPAddress]::Parse($IPAddress).GetAddressBytes()), 0)
    [int]$Mask           = [System.Net.IPAddress]::HostToNetworkOrder(-1 -shl ( 32 - $CIDRBits))

    # Determine whether the address is in the range.
    if (($BaseAddress -band $Mask) -eq ($Address -band $Mask)) {
        $true
    } else {
        $false
    }
}