According to STUN RFC 3489:

Symmetric: A symmetric NAT is one where all requests from the same internal IP address and port, to a specific destination IP address and port, are mapped to the same external IP address and port. If the same host sends a packet with the same source address and port, but to a different destination, a different mapping is used. Furthermore, only the external host that receives a packet can send a UDP packet back to the internal host.

In the Symmetric NAT scenario, when Alice accesses Bob and Registry respectively, Alice's external IP and port may be different because of the different destinations. I wonder if wgsd works properly in this scenario. Thanks!