# Player vs player (PvP) Multiplayer in F.LF is limited to network synchronization between 2 peers. It is backed by [F.Lobby](https://github.com/Project-F/F.Lobby) PvP technology, which utilizes a client-server architecture. ## Local usage ### starting servers #### web server F.LF itself must be served via `http:`, not `file:`. Any simple web server works, for example: ``` $ cd F.LF $ python -m SimpleHTTPServer ``` #### F.Lobby With node.js installed, ``` $ cd F.Lobby $ nodejs index.js --public ``` > The public flag means accept connections from any domain in your local network. As long as it does not serve the public, it should be safe. ### running F.LF Start F.LF from your local web server. Click `network game`. In the server list, selects `third party server`. Enter `http://localhost:8001` (or whatever port F.Lobby is listening). Click `Connect`. ### peering Enter a name and login. Speak. Click on a name to send a connection request. Click `Yes`. A dialog box should appear at the other player's window. If he accepted by also clicking `Yes`, then the Lobby window will close, and the 2 peers will attempt to make a connection. The message window will print `handshake success` at last if everything is okay. Click `OK` and `game start`. From now on the game runs like normal, but is perfectly synchronized with its peer. Shall the network lags, framerate will drop. If a peer closes, the connection is lost and cannot be recovered.