Skype not working with webfilter (Sophos WS500 but might be similar issue with others

[balticstar]

As a boarding school we allow boarders to have access to skype at the weekend to call friends and family abroad. Since we implemented the filter Skype stopped working as it doesn't seem to understand proxy settings. We tested one laptop and pointed it straight at our second (open) firewall it worked immediately. We obviously don't want to advertise this second firewall to pupils.

 

Has anybody experienced something similar?

[tom_newton]

Generally skype will traverse proxies - but it does not like any form of HTTPS mangling - either cert checking or full interception. A chap I was talking to on the Equiinet stand (I was just hanging out there for 5) at BETT suggested that some vendors have a technique for differentiating skype connects from reg'lar browsers. I shall be getting the packet captures out next week to see if this is indeed the case.

 

Meanwhile - check your filter logs to see if any connections are being attempted over "HTTPS" to bare IP addresses and getting blocked...