Technique for building a Multiplayer Server

I'm looking to write my own multiplayer game server (most likely in nodejs) and I was wondering what protocol I should be using to transfer data? Are Datagrams the norm to send information (i realize they don't confirm delivery like HTTP, that can written on top of the protocol)? Any suggestions of performant proven systems would be a real help.

I guess I'm looking for successful techniques in handling the data transfer quickly and effectively (maintaining state on the server and scaling are a separate issue that I have a solid understanding of).

I'm looking to initia开发者_StackOverflow中文版lly support desktop/mobile games (MacOS, iOS, and Android).

---

For all your protocol needs take a look at socketIO.

Basically your best solution is to rely on websockets which are TCP sockets. socketIO is just a nice cross-browser compliant abstraction.

Either you use standard long pulling techniques or html5 websockets. There is no access to UDP for browser <-> server.

---

There is a technology that is called RTMFP that Adobe introduced in the latest version of Flash (Flash 10). It allows you to do P2P connection and transfer data directly from a client to an other client without passing by the server. On top of that, it's using UDP to transfer data. I believe that this was originally designed to do video and audio streaming, but you can use it to pass data around.

However the main downside on this technology is the mobile since most of them don't support Flash. In this case you can use Socket.IO and use the server as a router of information as a fallback.

If you want to build your application in Javascript, you can still use it by bridging the functionnality to Javascript. If you want to take a look at a simple version of a bridge, you can take a look at this github project (I am the author).

---

As a C++ developer of Massive Multiplayer games for 10 years, I can tell you that most of your more advanced games, such as ones in which I was involved (Legends Of Kesmai, Magic: The Gathering Online, Airwarrior II, AVP, NTN Triva) to name a few, TCP is used for most communication simply because you need an ACK / NACK to be sure the data was received from the client. That is not to say UDP doesn't have it's place. In Legends we wrote the the protocol code to use UDP for out of bandwidth delivery of data which wasn't imperative that it be received in proper packet order and complete. Use UDP when you want to do things like update graphic files in the background while the user is playing, etc. This type of delivery is often used for such purposes and allows your TCP packets to arrive as required by your server.