For those who have installed a VLF monitoring station it is only one more step to put MP3 streaming audio on-line to the world. It is also a great opportunity for other researchers to listen to and process your signal as well. This has only become possible within the last few years. Now we look at the steps required.
FIND YOUR LOCAL
AND PUBLIC IP ADDRESS
(Remember you can use Google to convert Italian to your own language as needed)
Type the command “ipconfig” and press “ENTER” (1)
To find the Public IP address you can use one of many web sites available for this service. Open Google and type: “what is my IP address” and choose one of the web sites. One, for example is: http://www.myipaddress.com/
Accessing the home page this web page shows you the IP public address:
In the example “188.8.131.52” is the IP public address.
If your PC is connected directly to the web by a modem the two addresses will be the same: your public IP and the local IP address will be identical. If you are using a router your public and local IP address will be different as in example above.
Take note of the addresses we have found: we need
- an Audio Stream Server software, it is the “web
As in a FM broadcast station we tune a transmitter,
in a MP3 web station we point to an Audio Stream Server. Let's activate
our free server, called Icecast. Download Icecast from here:
download the executable file icecast2_win32_2.3.2_setup.exe and run it. The installation starts: always confirm the various questions until the end of the installation. Click on the Icon “Icecast2 Win32” on your desktop and open the stream server control window.
Click on “configuration” (1): a text window opens
with minimal setup/configuration.
There is important information in this file:
...that we can change. For a more complete set of parameters, read the instructions of the program: http://www.icecast.org/docs/icecast-2.0.1/
Now click on “start server” button to run the server.
Now the server should be active.
You should see a page like this:
This will be the control page of our server. Currently
there are no active streams of services because we have not yet activated
the source. Clicking on the page of "administration" will ask userid and
password: they are "admin" and "hackme" we have seen above. We can change
them by editing the "configuration" file opened in IceCast window, we saw
THE AUDIO ENCODER
Download the application from this web site: http://butt.sourceforge.net/
and run the installation file: “butt-0.1.12-win32.exe”.
When the installation finishes we start the program that opens the main
Clicking on “settings” we can put the configuration
parameters in, starting from the audio device we want as the signal source,
and following with all others parameters:
The images above are an example of how we can configure the program. Some parameters are open to choice, others must be the same as configured in IceCast: address, port number and password. Finally we also configure the parameters of the stream. The upload bandwidth provided by ADSL line conditions the values that can be used: An ADSL line with 240 Kb in upload will not handle more than 3 users connected to your stream: 240 Kb / 64 k bitrate = 3.75
Now we can run the program by clicking on Play button:
the windows info shows the connection parameters and reloading the IceCast status web page http://localhost:8000/status.xsl
we find this one:
Our stream is active! To listen locally to our audio
transmission we can click on the M3U button: it connects us to the stream.
The program we have set up windows to play the audio file will open: Windows
Media Player, WinAmp, VLC ... playing our stream. The address pointed to
The stream title (in my case) “Openlab” will show
in the “Media Player Window”.
THE STREAM BECOMES
In our example: http://localhost:8000/mount01.m3u
In the same way we can make the IceCast status web
page visible on the Internet:
AND ROUTER VIRTUAL SERVERS
If your PC is connected to a router we must instruct the router. It should know that the calls it receives on port 8000 must be redirected to the PC that hosts IceCast. This service has different names: some call it Firewall routers, others call it "virtual server". Each router has its own set of rules but the principle remains the same for all: the calls that arrive on the Public IP port 8000 must be sent to the PC with IceCast.
This is the same job we do with Emule to work with
But if we found the address changed, it means that our DSL has a dynamic IP address. It changes every time we turn our modem/router on or off. How do we fix this? Each time the router loses power we should change the address of the stream on the web page. A free solution exists and is called DynDNS (Dynamic DNS Free): http://www.dyndns.com/services/dns/dyndns/
As described on their website: “DynDNS Free allows you to create a hostname that points to your home or office IP address, providing an easy-to-remember URL for quick access. We also provide an update mechanism which makes the hostname work with your dynamic IP address.”
To activate the service you have to open an account, choosing a host name: it may be, for example, "john.dyndns.info”. Completing the registration you download a program to install on your PC. Once active it will get in communication with the server DynDNS keeping your IP address in sync with the host name you choose. Your public IP will always be associated with the host "john.dyndns.info”.
The IP address may change but the host name will
remain the same.