A simple class for defining an IPv4 address, accessing or changing any octet. Uses the Version object as the base object.

IP Address Class.ps1

class IP {
    IP([string]$Address) {
        $this._IPAddress = $Address
    }
    hidden [Version] $_IPAddress = $($this | Add-Member ScriptProperty 'Address' {
            # get
            [PSCustomObject]@{
                First  = $this._IPAddress.Major
                Second = $this._IPAddress.Minor
                Third  = $this._IPAddress.Build
                Forth  = $this._IPAddress.Revision
            }
        } {
            # set
            param ( $arg )
            $this._IPAddress = $arg
        }
    )
    [string] ToString() {
        return $this._IPAddress.ToString()
    }
    [IPAddress] ToIPAddress() {
        return [IPAddress]::Parse($this._IPAddress.ToString())
    }
}