'get ip addresses for a given domain name, example domainName = www.google.com
    Private Function GetAllIPAddresses(ByVal domainName As String) _
        As System.Collections.Specialized.StringCollection
        Dim results As New System.Collections.Specialized.StringCollection
        Dim hostInfo As System.Net.IPHostEntry = System.Net.Dns.GetHostByName(domainName)
        For Each ip As System.Net.IPAddress In hostInfo.AddressList
            results.Add(ip.ToString)
        Next
        Return results
    End Function