Seeley Article

You might not immediately associate bucolic Cedar Falls, Iowa, with cutting-edge technology. However, the town's own University of Northern Iowa is out to shatter any backwoods stereotypes. Starting in 1999, the university began working on a state-of-the-art multimedia distribution system. The idea, according to Rick Seeley, Instructional Technology research and development coordinator, was to provide a technology infrastructure that could facilitate both creative and practical digital learning. "We wanted to provide the tools that would let our faculty and students incorporate multimedia into what they were doing," he said. "So far, it really seems to be working." 

At the core of the University's multimedia distribution system is what's called Web streaming technology. Web streaming is an alternative to the older, more time-consuming method of delivering audio and video to a user's desktop. Instead of waiting for the entire file to be downloaded before it can be played or viewed, streaming technology sends a continuous flow of packets, or pieces of the audio or video file, down to a user's desktop either over a private network or the Internet. As soon as the packets begin to arrive, the file can be reassembled and played, as long as the user has the appropriate desktop software or Web browser plug-in. Streaming technology can be used to send previously recorded files or events down the wire, as well as to transmit live events like a visiting professor's speech.

At the University of Northern Iowa, students and faculty are using streaming to send an interesting smattering of materials out over both its high-speed fiber network and the Internet. Currently, the campus radio station uses both routes to send audio streams to listeners. In addition, faculty members can encode videos of their lectures and even of copyrighted videos and make them available online. Faculty members are also using the system to share lectures and research materials with overseas colleagues exploring similar areas of study. 

This same media distribution infrastructure supports a research project called INTIME, which stands for Integrating New Technologies Into the Methods of Education. Teachers participating in this study can use what the university has built to post video case studies of methods that have been successful in their K-12 classrooms when it comes to incorporating technology into lesson plans. These videos, of which there will eventually be around 600, can be searched and viewed by interested educators around the world. 

In addition to these applications, university faculty and personnel also conduct multimedia video conferences over the infrastructure. The university has embraced live streaming as well. More than 70 athletic events are streamed as they happen each year, as are speeches delivered by visiting lecturers or even University President Robert Koob.

WHAT MAKES IT WORK

For the distribution system, the university's Center for Educational Technology built a multi-terabyte storage area network (SAN) where the multimedia files are stored and from which they're accessed. In addition, there are currently four media servers in place from Real Networks. The university also maintains a production facility where faculty and students can check out video cameras and then work with the staff to create their own multimedia objects that can be accessed via the distribution system.

Part of the job of the production staff is to make sure the video or audio content is properly prepared for its digital distribution, a process that is overseen by Production House manager Charles Sengstock. For non-digital content, such as videotapes or audio tapes, the basic digitizing process involves taking what are analog signals and converting them into digital packets, the small pieces of data mentioned earlier that can easily travel over an Internet Protocol, or IP, network. For newly created or live content, the staff captures either the video or audio using digital video cameras and recording devices as well as MPEG-1 encoding cards, encodes that data into MPEG-1 standard format, and then converts those into the RealMedia format. Though the University of Northern Iowa has standardized on products from Real Networks, digital content can be created with video and audio production tools from a broad range of companies, including Adobe, Apple, and Microsoft.

Once files are created, there's always the question of which format or formats to store them in. The most prevalent standards for digital content are the MPEG (Motion Picture Experts Group) standards. Most of the major Web streaming vendors–including Apple, Microsoft, and Real Networks–support some version of the MPEG standards in their streaming product families. These ensure that all audio and video files are compressed and delivered the same way, so that the player software on the user's desktop knows how to decompress, assemble, and play them. In addition to MPEG, the streaming vendors have developed their own formats (Real G2 from Real Networks, Windows Media from Microsoft, and QuickTime from Apple) which are tuned to the specifications of their respective media servers and players. As noted above, the University of Northern Iowa stores master copies of its video and audio files in MPEG-1 format, but then converts them into Real's format. "This gives us a much cleaner end product and it also saves us time when Real Networks updates its format," Sengstock explained. 

WHAT USERS AND NETWORKS NEED

Once content has been created, formatted, and stored, it's time for the streaming servers to do their jobs. For Web streams sent out over the Internet, or even for those delivered over a private network like the university has on its campus, a streaming server is an obvious requirement. This software works in conjunction with Web servers. When a user clicks on a link for either an audio-only or video Web stream, the Web server sends a message to the streaming server. That message tells the server to check first how much bandwidth the user has available. Once information about the user's connection has been processed, the streaming server can start sending the encoded packets over the network at a rate that makes the most sense for the available bandwidth. 

There are several streaming media servers on the market today, including those from Apple, Microsoft, and Real Networks, and most will stream content in multiple formats. Microsoft now incorporates its Windows Media Services into the Windows 2000 operating systems and Windows Advanced Server. The technology is also available for Windows NT via download. Apple offers its Darwin Open Source Streaming Server for free. Real Networks charges for its server based on the number of streams a company anticipates having to deliver at once. However, regardless of the vendor or the pricing model, all of these software servers are built to deliver several hundred to several thousand Web streams at once. 

For users to view Web streams, they need the right software and media players. Students and faculty at the University of Northern Iowa rely on the Real Networks RealMedia Player. Media players are also available from Apple, Microsoft, NullSoft, and others. Basic versions of all these players are available as free downloads, but the players are often incompatible with the streaming file formats of other vendors. However, as Sengstock and Seeley pointed out, the University of Northern Iowa has the advantage of a relatively closed environment, which means it can mandate the software choice of its end users. 

Though there's plenty involved in delivering multimedia with Web streaming, if you can get all the details worked out, the payback can be significant. If you don't believe it, ask just about anyone at the University of Northern Iowa. "You just can't believe how great it is to see students and faculty members come into the production facility and figure out some super-effective way to use streamed video or audio," said Sengstock. "I'm just more excited than ever about what this technology can do."