R – How to use sockets in Silverlight 2

silverlight-2.0sockets

I am trying to implement a Silverlight 2 client application that takes data from a server via socket-based communication.

I've heard that in Silverlight 2, this process is more complicated due to the fact that it is required to use a policy server, and that could slow down my application, not to mention that each string passed through the socket would have to be checked with the policy server.

I'm wondering if this is indeed the case, and if writing the server is going to be a mammoth task. Do you recommend staying with Silverlight 1? I'm aware that in Silverlight 1, socket communication has to be done in ASP.NET. I was aiming for the client logic to be done in C#, but with Silverlight 1, I believe I can only use Javascript and communicate with ASP.NET…

Thanks for any replies!

Best Answer

According to documentation, you can use sockets to connect to the server the Silverlight app was downloaded from right away. If you need to connect using sockets to another server, you need to supply a policy file.
This MSDN article describes how to create the policy file.

Related Solutions

Sockets – How does the socket API accept() function work

Your confusion lies in thinking that a socket is identified by Server IP : Server Port. When in actuality, sockets are uniquely identified by a quartet of information:

Client IP : Client Port and Server IP : Server Port

So while the Server IP and Server Port are constant in all accepted connections, the client side information is what allows it to keep track of where everything is going.

Example to clarify things:

Say we have a server at 192.168.1.1:80 and two clients, 10.0.0.1 and 10.0.0.2.

10.0.0.1 opens a connection on local port 1234 and connects to the server. Now the server has one socket identified as follows:

10.0.0.1:1234 - 192.168.1.1:80

Now 10.0.0.2 opens a connection on local port 5678 and connects to the server. Now the server has two sockets identified as follows:

10.0.0.1:1234 - 192.168.1.1:80  
10.0.0.2:5678 - 192.168.1.1:80

R – Silverlight 4 and TCP Sockets

In the beta, for trusted out of browser mode, sockets are still port restricted but it looks like they're planning on lifting this restriction by RTM. The policy file is not required in trusted mode.

Best Answer

Related Solutions

Sockets – How does the socket API accept() function work

R – Silverlight 4 and TCP Sockets

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