Defender fwrite() errors

With debug turned on my log file fills up with error messages from Defender failing to fwrite() as below - looking at the code I see it is attempting a udp connection to so my question is why is it doing that in the first place and why is it failing? Is this also slowing down my site? Is it necessary?

[16-Dec-2016 14:54:36 UTC] PHP Notice: fwrite(): send of 93 bytes failed with errno=1 Operation not permitted in /home/[Moderated]/public_html/wp-content/plugins/wp-defender/app/module/audit-log-module/controller/class-wd-audit-logging-controller.php on line 57