My current approach is simply to connect the nodes to a central server, which performs aggregation and provides services externally, similar to the way bostr does it.
I still need time to learn and test how nodes communicate with each other.
Discussion
If your using nodejs, I've had some success using holesail and hyperdht. But I don't know how they work under the hood and I don't know how censorship resistant that are
WebRTC might also be cool to use, then I could be compatible with browsers...
Thank you for your guidance! I will continue to do some testing and research. Due to the complex network environment in China, most people cannot connect to public Nostr relays. Therefore, I am still exploring some possibilities.