How your screen travels

The picture goes straight from one Mac to the other, over your cable or your local network, and never through our servers. It isn’t encrypted.

Applies to both MacsUpdated 5 October 2026

Direct. Your screen never passes through our servers, and we never see it.
Not encrypted. On a cable, only your two Macs are connected. On a network, someone with access to the same network and the right tools could see the picture. Use Wi‑Fi and Ethernet on networks you trust, such as your home, and the cable on shared or public networks.
No pairing. Any Mac running Second Display on the same cable or network can find your display Mac and show its screen there, in a window of its own. That’s all it can do: it can’t type, click or switch anything on the display Mac.

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