Both BitTorrent Sync and Syncthing need a particular port in the firewall to be open (or port forwarded). I&#x27;m a contractor that&#x27;s almost always on the client site, and corporate firewalls are not opening up because I&#x27;d like it so. I&#x27;ve been using ownCloud for the past year and since it just uses the https&#x2F;443 port, it works everywhere.