Ronan Gouello on "[Plugin: Wordfence Security] Strange HTML code in page"

Hello, I see the below strange code in the HTML. Is that normal? If normal, what is it for? If not normal, how can I remove this?

Thanks,

Ronan

<script type="text/javascript">var src="http://www.mywebsite.com/wp-admin/admin-ajax.php?action=wordfence_logHuman&hid=C75F01E4DEC.........."; if(window.location.protocol == "https:"){ src = src.replace("http:", "https:"); } var wfHTImg = new Image(); wfHTImg.src=src;</script>

http://wordpress.org/extend/plugins/wordfence/