Custom dedicated server

Hello,
the dedicated server delivered with the UE isn’t made for scalability and only for 64 players per server.
That’s why I consider building an own server (with multiple instances, proxies servers etc) for making the server scale for a massive number of players, in fact for an MMORPG.

Since it is enough work to do the server part I wondered if there is a documentation on the protocol Unreal uses for its Client/Server model.
That way I could build the protocol on top of my custom server the way the clients directly understands its actions (such as position sync, remote triggers etc.).

Is there a way to do that? I wouldn’t want to do reverse engineering on the protocol with Wireshark or do a long research on the source code.

Is this a good idea to do such or should I build an own protocol and implement it client-side as well?
And if so, is there a cross-platform library for networking included in UE4 already or do I have to use native ones of the OS.

Thanks for your time and answers

If you decide to implement your own protocol, you can use the Sockets module - all the needed system related network code is already there.