音频数据的TCP套接字通信 - 多服务器到多个客户端

Question

I am new to socket programming and don't have much idea on how it works, Here is the use case, Im developing an iPhone app, where users stream real time audio originated from another iPhone device (in short Multi casting)

What I have done so far:

I opened a port on server which keep listening to incoming data from clients. On the iOS side, i implemented methods thats read the packets received on the server and process it accordingly (i have used GCDAsyncSocket)

Problem where I need help:

The above use case works perfect for 2 users, one that sends the audio data to the server and the other one reads that data to play audio. But actually there would not always be a single user originating audio data, they could be more than 100+, Now when all of them are sending different audio data to server how could i filter data for the listeners that everyone receive only there data, I overcome this problem adding a token on every packet like

unique_token:<ffdefa09 fedead3...... //Audio Data

But this process is way too slow as every client is listening all the packets and only process the ones with the token they are assigned.

Is there anyway, we can make a peer to peer connection by which the originating device become server and only sends data to its listeners and don't bother anyone else?

Answer 1

Can't you add something like a light protocol before you start steaming audio data to server ?

iPhone -> server [Request: Start Stream Audio]
server -> iPhone [OK: TCP Port:4444]
// iphone sending audio packets to port 4444


iPhone2 -> server [Request: Start Stream Audio]
server -> iPhone2 [OK: TCP Port:4445]

then the server can filter all audio channels with TCP port ID instead of packet ID (or maybe I misunderstood your issue)

Btw I don't think you can do any "real" P2P with iPhone on cellular networks because of providers firewalls

Answer 2

for every end who send the audio data, you create a socket and recv audio data, and for every end who receive the audio data, you create a socket and send audio data. P2P is lots of work , because many device are behind the public address.

Answer 3

You need to separate your command data from your streaming/audio data.

First you need the iphones to tell the server what they want,

• iphone 1: "i want to stream this data with id 1"
• iphone 2: "i want to listen to stream with id 1"

that way the server can tell the iphone where to connect for getting the data it needs, as HaneTV suggested with port numbers