I have set up BittorrentSync on my laptop computer (windows 10), on my server (Windows 2012 server) and on my iPhone. All devices are located at home. On the Windows 10 computer I have installed the Desktop Version of BittorrentSync, on the Windows Server 2012 I have installed BittorrentSync as a Windows Service.
My strategy is to sync several folders when I am located at home, so "LAN only". I am not interested to sync stuff when I am on the road.
But I was very surprise to find out that when I am outside my LAN (office, public Wifi etc), BIttorrentSync on my iPhone shows my home peers as connected an also data is synced. I wonder how this can happen, as I never opend a firewall Port on my home's LAN router. As I understood, no BittorrentSync central servers are used.
Somebody can help my understand the technology?