For peer-to-peer connectivity within a LAN, the sender and receiver don't need to be on the same subnet. (#1022)

Even with NAT routers in their respective local networks,
a receiver behind NAT can establish direct access to the sender without requiring internet connectivity.
Conversely, the local networks on the sender and receiver may overlap but not be connected.
This often occurs with 192.168.0.0/30 and 192.168.1.0/30 subnets.