In the iCloud Control panel I find a feature calles "Access to my Mac" (in German: "zugang zu meinem Mac") What is it good for? What happens if I check it?
I think that is Back To My Mac, BTMM.
iCloud- Setting up and using Back to My Mac with an 802.11n-based AirPort base station, or Time Capsule
Mac OS X 10.7 Help- Use Back to My Mac
OS X- Using and troubleshooting Back to My Mac with your iCloud account
Setting up and using Back to My Mac with AirPort base station or Time Capsule
Supported router devices for Back to My Mac
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