Port 7680: Delivery Optimization
Port 7680 is used by Windows Delivery Optimization to share Windows and Store updates between PCs.
What runs on port 7680
Windows 10 and 11 include Delivery Optimization, which lets PCs download pieces of updates from each other instead of all fetching them from Microsoft. The service (DoSvc) listens on TCP 7680 for other PCs asking for those pieces. It is why many people discover this port on their own computer and wonder what it is.
On a home network
Any Windows 10 or 11 PC with Delivery Optimization enabled may show 7680 open to other devices on your LAN. It is Microsoft's own service, not malware.
If port 7680 is reachable from the internet
Inside a home network it is harmless and expected. It only matters if the PC is directly reachable from the internet, in which case the thing to fix is the forwarding or DMZ rule that caused it, not this port. Windows lets you limit sharing to your local network or turn it off.
How to check whether it is open on your network
On Windows, open Settings, Windows Update, Advanced options, Delivery Optimization, and choose whether to allow downloads from other PCs. A LAN port scan will show 7680 on PCs where it is active.
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