phone.setSerialNumber("001122334455");
phone.setSerialNumber("0011aabb4455");
    public void testGetFileName() throws Exception {        ClearonePhone phone = new ClearonePhone();        phone.setSerialNumber("001122334455");        phone.setTftpRoot("abc");        assertEquals("abc/C1MAXIP_001122334455.txt", phone.getPhoneFilename());    }