Help me a solution for a .NET real-time application

Question

Hello everyone, I am developing a system which include a server app & a client app, note: the number of clients can be to million. These are my requirements:

• Client must authenticate (username & password) to server to be accepted connection. And client will listen to server, and receive any data which sent from server.
• When server has data, server will send to all connected clients.

Please help me some solution. Note: client is a WinForm application, and server is any kind of application which it can send data to all connected clients.

P/S: At the moment, my project use .NET Remoting but it is not suitable with my requirements because server can not send data to clients. I make a trick: Each client will send request to server each 2 seconds once to check that server has new data or no. If yes, client will receive data. I need a new solution to replace.

Thanks.

Answer 1

If you are using web services I think it can't be accomplished since it is always synchronous.

Answer 2

Well you need to start by asking yourself and important question, is a 2 second poll interval really a requirement? Can you make it less frequent.

Do you in fact want to use frequent polling, or would you prefer to use another technique such as long polling (where a connection is held open until there is new data, then it is closed and recreated) or a true comet/PUSH setup where the connection is always open.

Another important question is how much load is this site going to be under, a few users? a hundred, a million?!

Answer 3

Take a look at Duplex WCF Services

Word of warning, this does not work over https.

Alternatively the Windows Azure Service Bus also supports Duplex communication.

Answer 4

Have you looked at Jabber (XMPP)? Your need seems tailor-made i.e. you can trigger a send based on certain events etc. plus stateful data transfer etc.