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Stream audio to several clients

I am making a website using ASP.NET and i have a webservice using WCF.
I need to figure out how i can stream audio(.mp3 files most likely) to several clients, so that all the clients hear the same, at the same time. I know this can be done using sockets, but I need a lot of different streams(which is not so good with sockets as i would need a new port to every stream, as far as know).
It is a kind of online radio-ish. Several channels, and users can then listen to the one they want.
Can anyone help me or point me in the right direction for something like this?
It does not have to be through WCF, I just need to figure out some way to do this

A quick way to get started with this is to just use SHOUTcast or Icecast.
They both work very similarly, providing an HTTP or HTTP-like server that streams MP3.

Transferring binary data using sockets?

I am thinking of making a server/client application that does this: the client(s) will connect to the server and the server will send back a list of folders (probably music or videos) that the client will be able to stream or download. I am going to make a GUI for this so that it won't be a text-only interface. I want it so that when the client connects to the server and gets the information about the media files that can be streamed/downloaded, the client will show the folders/files in an explorer-like interface (folders will show up with a folder icon, videos will show up with a video icon, etc.)
This seems really big to me but I really want to learn more about socket programming with C# and feel that getting my hands really dirty is the best way. As you can imagine, I have a lot of confusion about how to start this and what it is that I need to do to make this work.
The first part of my question is: If I want to let a client receive a list of files/folders and also have the ability to download/stream them, do I need to do something with transferring binary data using sockets or am I completely wrong on that? If I'm wrong, do I need to use something else like file readers and somehow use them over sockets?
The second part to my question is: when I transfer this information over to a client, how can I make the client show the appropriate icons for videos, folders, mp3s, etc.? I'm thinking that if I have to transfer binary data I will have to use that data to somehow populate the client GUI with the correct icons/data. I am stuck on exactly how to handle that. Are there certain methods/classes that I can use to parse that data and do what I want to do with it? Again, I don't know if I'm wrong about needing to transfer binary data but either way I am confused on what it is that's necessary to handle this.
I apologize if any of my terminology is wrong. I am obviously not an expert in C# yet ;)

Any time you are sending data between machines (or between processes), you are already talking binary data (you could argue that everything is binary data, but when working with it as an OO model it doesn't feel like it). The point here is that all you need to do is serialize your messages. There are a myriad of serialization frameworks - some aimed at convenience, some aimed to range-of-features, and som can use aimed at performance (minimum bandwidth etc).
Even the inbuilt ones would work - for example, you can use XmlSerializer etc to write to a Stream (such as the NetworkStream you typically use with a socket). But please - not BinaryFormatter (it will hurt you, honest). Personally I'd use something a bit less verbose such as protobuf-net, but I'm somewhat biased since I wrote it ;p
However, note that when working with sockets, you are typically sending multiple (separate) messages as part of the conversation. In order for each end to correctly and conveniently read the right data per-message from the stream, it is common to prefix each message with the length (number of bytes) - for example, as a little-endian int taking a fixed 4 bytes. So the reading process is:
read 4 bytes
interpret that as an int, let's say n
read n bytes
run that data through your deserializer, perhaps via MemoryStream
process the message
and the sending process might be:
serialize the message, perhaps to a MemoryStream
query the length and form the 4 byte prefix
write the prefix
write the data

You don't have to go to as low level as Socket, unless you just want to learn of course.
I suggest using WCF. It will completely meet your requirements, will be flexible and you will not have to deal with sockets directly.
WCF is a big framework, but you can quickly learn how to use it.
Introduction to WCF
Here you can find how to retrieve and show file icon in Windows.
If you client is hosted by Windows, you don't need to transfer icons, you can just retrieve image on the client by filename/extension.

Help Conceptualizing XML HTTP POST Automation through Application Layer

For this post, I'm looking for more conceptual help than a specific technical solution (although anything helps).
Basically, I've been asked to automate an XML HTTP POST through an application layer. I've never done anything like this before, so I'm a bit confused where to even start on a high level. It would be great if someone could share with me what steps I would need to take to accomplish this task. Here is some more background information:
Currently, our company uses an application (we'll call it Program.exe) on a daily basis to design front-end interfaces with a visual editor. Once the interface is completed, Program.exe creates JSP files and submits them to the server. Unfortunately, the process of creating and sending the files takes an awfully large number of clicks, so management would like to automate this process by running a script that would take the project files from Program.exe, convert them to JSP and accurately submit them through the application layer of Program.exe to the appropriate server.
So far I have used WireShark to sniff the packets of a simple transaction using Program.exe and discovered a number of HTTP/XML POST packets that contained XML data with information like "Current File Name" "User name" and more. Curiously, all of these data items were submitted in different packets, not all in one. There are also multiple references to SOAP. (I have almost no knowledge of SOAP, except that it exists)
At this point, this is all of the information I have. I am unsure what steps I should take from here. I would really like to understand this process on a high level, so any conceptual information would be greatly appreciated.
Finally, we use C# primarily for these sorts of tasks, so if someone would like to share a technical solution feel free to use C#.
Thank you all very much.

I would tackle this by completely ignoring the expected method of solving the problem (generating an HTTP POST) and instead focusing on what the actual problem is.
What are your inputs? A bunch of JSP files by the sound of it.
What are your outputs? The same bunch of JSP files.
What has to be accomplished? Moving the inputs from one know location to another.
Now with a well defined problem, a solution is much more likely to clearly present itself.
For example, by looking at the problem I've defined I would think that XCopy would be an elegant solution to the problem.
Any time I get handed a solution and then told to go solve a certain problem, I am always highly suspicious of the tool I've been given. If they knew that this was the best solution to the problem, why didn't they do it themselves?
My advice: Find your own solution.
Hope that helps!

Send files between python+django and C#

i would like to know, what is the best way to send files between python and C# and vice versa.
I have my own protocol which work on socket level, and i can send string and numbers in both ways. Loops works too. With this i can send pretty much anything, like package of users id, if it is simple data. But soon i will start sending whole files, maybe xml or executables.
Simple server with files is no an option because i want sending files from client too.
I was thinking about serialization but i don't know it is the best solution, but if it is i will love some tips from stackoverflow community.
EDIT:
I added django to question and chose http.

RPC may be a good idea for you, because it's relatively very high level. Instead of defining your own server and protocols, you can simply remotely execute routines over the network, pass in arguments and get back results.
For example, both languages have libraries for XML-RPC.

The easier way on my use case was send files using HTTP because with python i have additionaly running django.

Best API for modeling networked devices with arbitrary attributes to learn from?

I need to design a new API which models networked devices which have a large amount of attributes which vary quite a lot based on the device's type. The attribute set is not totally arbitrary though, it is a big set of known attributes. That said, with new devices come new attributes so the situation is never totally fixed.
The network devices themselves come and go all the time so that's a central part of the API design. Also, it would be preferable to get updates on the attributes/attribute sets via some variant of the Observer pattern.
Note: I'm not talking about network management, although this might sound like that. That said, the APIs on those systems might very well be suitable/worth looking at.
So my question is, do you know any good APIs out there in the Open Source world from which I could learn and derive some inspiration from?
The system will be Java-based so the examples would preferably be from close relative languages, e.g. Java (of course :)), C#, Scala and other similar statically typed languages.

I'm not sure what exactly your API is intended to do, but I'm guessing that since the network devices "come and go all the time" and that you wanted to use the observer pattern, you're looking for something that can get updates on the current state of stuff out on the network.
Have you looked at SLP? It's a pub/sub protocol that may do what you want: it lets network devices broadcast their presence and properties out over the network and also listen for other people. It works over TCP and UDP (unicast and multicast).
There's a couple of java implementations around (like jslp for example), but I was never entirely satisfied with them (so I ended up writing my own). As far as C# goes, I couldn't find one easily.

Not positive that I understand your question completely, but I'll give it a shot.
Are you looking for a way to allow a device to publicize its attributes when it is on a network? If so, there really isn't a good way unless you write code that understands now to interact with the device. After you have something like that, all you need to have is a class which holds attribute data in some type of data structure of your liking. For updating, you will probably need to poll the devices periodically unless they have a way of reporting when their attributes change:
Dictionary<string, Dictionary<string, string>> deviceAttributes = new
Dictionary<string, Dictionary<string, string>>();
void AddAttribute(string deviceIdentifier, string attribute, string value)
{
if(!deviceAttributes.Keys.Contains(deviceIdentifier))
deviceAttributes.Add(deviceIdentifier, new Dictionary(attribute, value);
else
deviceAttributes[deviceIdentifier].Add(attribute, value);
}
If each device has some kind of standard method for retrieving the attributes of interest, you can write code that would accept an array of whatever and add that to the data structure using a for or foreach loop. I can't really say more without more specific knowledge of what you are trying to do.

I might look at LDAP/ActiveDirectory/ADAM(User Mode Active Directory) . . .
TheEruditeTroglodyte