I want to create a mobile app which can connect to devices having the same app installed without having a server in between. The devices should act as server and client and discover nodes similar to them, like how it happens in block chain?
I firstly want to know the discovery protocol that how these devices will discover each other. I have seen the samples of sockets, TCP connection but they know the IP address before, in my case we do not know the IP address, have to discover similar nodes also with security like cryptography happens in block chain so, random device don't mess up with my chain.
I am starting to learn about it, and one of the first things that came to my mind is RPC, because is how Bitcoin works: link, and you can check also de P2P section in the link.
I will follow this and update my answer with the things I'll find.
Good luck.