CAS server log

Hi, 

I am trying to shut a CAS server and need to make sure no one connects to it.  

Would someone take a look at the attached IIS WEB log from the CAS box and advise how the user connects to it (10.1.50.111)?

***********************************************************************************************************************************************

2016-06-10 04:29:22 10.1.50.111 POST /Autodiscover/Autodiscover.xml - 443 BCM\jdavis 10.9.18.55 Microsoft+Office/14.0+(Windows+NT+6.1;+Microsoft+Outlook+14.0.7166;+Pro) 200 0 0 951
2016-06-10 04:29:22 10.1.50.111  POST /EWS/Exchange.asmx - 443 BCM\jdavis 10.9.18.55 Microsoft+Office/14.0+(Windows+NT+6.1;+Microsoft+Outlook+14.0.7166;+Pro) 200 0 0 390

***********************************************************************************************************************************************
Thanks