When my laptop, a Dell XPS 15 (9530), is connected to my WiFi network, a new network with the SSID "DIRECT-IE[laptop name]msSP", where "[laptop name]" is replaced with the name of the computer.
Interestingly, this network is on the same channel as the network to which the laptop is connected, and this changes if I change the channel setting on the router.
The effect persists even if the hotspot feature on the laptop is turned off, and only appears when it is connected to a network.
I was wondering whether this is some kind of WiFi Direct feature, but it does not appear when I search for WiFi direct-enabled devices using my smartphone.
UPDATE: In Task Manager, two network connections are shown, one being the normal connection. However, the other, with no activity, is labelled "Microsoft Wi-Fi Direct Virtual Adapter #3", with the SSID listed the same as the aforementioned cryptic network name. It appears Windows thinks it is connected to the network originating from this very computer.