def METHOD_NAME(session, tar_speed, tar_duplex):
    """
    Start the test according to the guest's os.
    param tar_speed: target speed expected
    param tar_duplex: target duplex expected
    """
    if os_type == "windows":
        run_test_windows(session, tar_speed, tar_duplex)
    elif os_type == "linux":
        run_test_linux(session, tar_speed, tar_duplex)