Micron Document

AutoInterface
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AutoInterface is an IPv6 based peer discovery interface that automatically connects to other discoverable nodes over local Ethernet or WiFi, without requiring IP infrastructure like routers, switches or DHCP servers.

It does however require that multicast UDP traffic is allowed on ports 29716 and 42671, and that link-local IPv6 addresses are enabled (which it is by default on almost all operating systems).

RNS has only AutoInterface enabled in its default configuration.