Webcasting with CTER Radio

Webcasting with CTER Radio

This document explains how to use the CTER SHOUTcast server to broadcast live and archived MP3 audio streams. It is intended for instructors or support staff who want to use the server for educational purposes.

Please note that the CTER SHOUTcast server is for academic use by faculty and staff at the University of Illinois. Users not affiliated with the University of Illinois need to run their own server or make arrangements with a private provider of SHOUTCast services. The user forums on the SHOUTcast web site often have announcements and advertisemements from private server providers.

How does it work?

SHOUTcast uses a three-part system. Each part can be (and usually is) on a different computer.

The broadcasting software. This is the software that runs on the instructor's computer. It takes audio from a microphone (or other audio source, such as a CD) and encodes it into an MP3 audio stream. The audio stream is then transmitted to the server.
The server software. This software takes the audio stream coming from the instructor's computer, duplicates it to multiple streams, and send a stream to each listener. This program runs on one of the servers in the CTER office.
The listening software. This software runs on the student's computer. It takes the incoming MP3 audio stream from the server, converts it back to normal, uncompressed audio, and plays it for the listener.

This system, while slightly more complicated than going directly from the broadcaster to the listener, offers a major advantage. The broadcaster (in this case, the instructor) doesn't need a very fast Internet connection even if there are many listeners. The instructor's net connection only needs to be fast enough to handle one audio stream. The CTER SHOUTcast server takes care of duplicating the stream and distributing it to the listeners over the University's high-speed Internet connection. This design also allows servers to mirror broadcasts that are taking place on other servers, making a SHOUTcast system able to handle an extremely high number of listeners.

How do I broadcast?

You need an MP3 encoding program with SHOUTcast-compatible broadcasting capability. There are many different packages to choose from. CTER recommends and supports Winamp with the SHOUTcast DSP plugin for Windows, and Audion for the Macintosh. If you choose one of these packages, CTER Technical Support can help you get set up. There are several other packages on the market that will also work fine.

You'll need to configure the sortware to work with our SHOUTcast server. The exact steps will vary depending on the software, but at a minimum you'll need the following information:

Host name: cternt1.ed.uiuc.edu.

Port number: Try 8000 first. If that doesn't work, try 8001.

Station name, Genre: these are optional, however if you want your broadcast to show up in the public directory at shoutcast.com, you need to enter something. We suggest "CTER Radio" for the station name and "Education" for the genre, but feel free to use different values if you wish.

Server password: Contact CTER Technical Support for this.

Be sure that you set your encoder's bit rate (possibly called "audio quality" or something similar) to a fairly low setting or listeners on dialup may experience dropouts and delays. We've found that 16 kbps mono is plenty for voice-only broadcasting. Your software may not have this exact setting. That's fine. Just choose the closest one.

Contact CTER Technical Support if you have difficulty configuring your broadcasting software.

How do my students listen?

Your students need software that can play streaming MP3 audio. Again, there are many choices. WinAmp and RealPlayer are popular choices for Windows. Audion, iTunes, and MacAmp are popular choices for the Macintosh. We have detailed instructions for listening with WinAmp and ReaPlayer. Instructions for listening with Audion, iTunes, and MacAmp are forthcoming. In the meantime, contact CTER Technical Support if you need help configuring your listening software.

Can I archive my broadcast?

Yes. You'll need special software (called a "stream ripper") that can record your MP3 broadcast as it's occuring. CTER uses and supports StreamRipper32, a free program for Microsoft Windows. Once you've recorded the broadcast in MP3 form, contact CTER Technical Support and arrange for us to put your archived file on the server.

Are there limits on what I can broadcast?

While broadcasting your own voice, reading your own original lecture material, is perfectly legal, you should be aware that there are issues involved with broadcasting material which is copyrighted by a third party (such as a music CD). We have provided a brief summary of our understanding of the law. Be aware that we're not lawyers and this is not intended as legal advice. If you're planning to broadcast copyrighted material owned by others, you should consult an attorney before proceeding.

Document created by Tony Hursh, Oct. 18, 2002