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Open-source webcasting and media archiving software for e-learning

By Ron Baecker, Kelly Rankin / October 2005

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For the past five years we have been conducting research and development on a software project now known as ePresence Interactive Media. ePresence is a Web-based streaming (Webcasting) and collaboration tool for large-scale broadcast of events over the Internet---from university lectures to public health briefings to annual meetings to readings by authors [2, 3, 4, 12]. Events are streamed live and can later be easily deployed as browsable, searchable archives accessed through a customizable Web portal. Webcasting itself is non-interactive, which is overcome by combining it with interactive features. For example, ePresence currently employs text chat as a mechanism for allowing interaction among remote participants, and between these individuals and the speaker via a moderator.

ePresence is a powerful platform for research into large-scale collaboration and communication, and new features are always under development. For example, we are working on enhanced interactivity for all users, including those present in the local audience, those viewing remotely, and those viewing the archives, through both text and voice modalities. More specifically, we are studying the use of voiceover IP for questions to the speaker and for discussions among remote viewers [13]. Studies of how viewers use structured, navigable, searchable archives [8, 14] are underway, as is work on the automatic recognition of speech and especially of keywords on the audio track.

Over two years ago, we began receiving requests for our software, presenting us with the challenge of how to distribute ePresence. Many of those interested in the system intended to use it in e-learning, where appropriate technology must fit the organizational culture and philosophy of an educational institution. However, being a small research group in a university we were concerned about providing the necessary features required by all of our adopters. (To date, every organization that has adopted the system or used it in collaboration with us has approached its use in a different manner). To give ePresence adopters maximum flexibility in tailoring the system, we started to consider releasing the software on an open-source basis. This approach also promised to allow the technology to be adopted by individuals and groups who wanted to make use of e-learning but lacked the infrastructure and means to adopt expensive proprietary solutions.

Open-Source Software

Open-source software challenges traditional methods of technology transfer from universities that have, until now, relied exclusively on the packaging of proprietary products and on their protection through legal approaches such as copyright, patents, and trade secrets. The proprietary approach is clearly appropriate for hardware and pharmaceuticals, but needs to be re-examined for use with software and educational multimedia. We suspect that a balance between both approaches will be the norm by the latter part of this decade.

By now the concepts of "open source" and "free software" have become very familiar. They represent international movements in the collective development of software and other knowledge media. Open source refers to the practice of sharing source code with a community that is encouraged and empowered to read, comment, amend, and augment it [7, 16 see also]. Free software refers to a philosophical belief that software should be open and must remain open when redistributed, which some interpret to imply that only related services and not the software itself should cost money [17: see also].

These intertwined movements are arguably two of the most important forces shaping today's knowledge media industries [5, 6]. They are transforming the artifacts and the business and social practices of the software industry, but also are more broadly impacting the production and use of other knowledge media such as encyclopedias, scientific journals, and digital audio and video. In these latter manifestations, the movements sometimes go under the names "open content" and "open access" [10, 11: see also].

ePresence as a Case Study of Open-Source Software for E-learning

Having decided to distribute ePresence open source we found ourselves faced by a whole new set of challenges. We needed to decide which of the more than 50 open-source licenses, approved by the Open Source Inititative (OSI) and listed on were suitable for our project. We also struggled with one of the more critical issues of the open-source movement, that of a business or revenue model. If one "gives away" the software, how does one make money, or generate revenues sufficient to sustain research, development, and support? Not to mention, open-source development defies the philosophy of traditional software engineering of having a centrally-organized development team with well-defined top-down patterns of authority, responsibility, and control.

To better understand the open-source movement and find answers to our questions, we put on our thinking caps, did some research, and invited some of the movement's best minds to participate in a three-day conference during the spring of 2004 (see ). (Although, the last part is not necessary if you are planning an open-source release for your software project! However, we did discover we were not alone in our dilemma.)

Open-source licenses preserve the concept of copyright, but use it to encourage widespread copying, modification, and reuse of software rather than to discourage it. Perhaps the most fundamental difference is between those licenses that follow the pattern of the GNU General Purpose License (GPL), which insist that all derivative works be distributed under the GPL ("copyleft"), and those licenses that do not enforce this notion. The challenge is to master and employ to advantage one of these many licensing frameworks.

A classic solution to the problem of revenue generation is through the sale of packaged systems and services, a strategy employed skillfully by companies such as Red Hat (Young and Goldman Rohm, 1999). In other cases, such as MySQL, companies release their software under dual-license framework that includes both a GPL version for no charge and a commercial version that generates revenue.

With ePresence, we decided on a dual-license strategy. Early this fall we will release the source code for "ePresence Media," the core technologies for media capture and Web publishing, under an OSI compliant license. The other half of our dual-license strategy includes a second package known as, "ePresence Live!"---as in we're here to support you Live! By purchasing ePresence Live! adopters receive a membership in the ePresence Open Source Consortium. There are two membership packages available, Regular or Premium, each providing the adopter support and training services, source code for advanced technologies (such as the code for live Webcasting, licensed under a University of Toronto community source license), and many other benefits. ePresence source code has been available to consortium members since June 2005.

Another advantage of the dual-license model is the enhanced opportunity for testing and improving the technology. The goal is to form a strong community of institutions and individuals who will collaborate on future research and development. We also intend to migrate advanced technologies into the core system from time to time, and to generate a continued flow of new advanced technologies through research.

It took some time to work through the legal framework to do this from the University of Toronto. We first had to assign our "invention" of ePresence to the university, using their precedents, all of which are rooted in proprietary concepts. The university then had to assign management of the invention back to the Knowledge Media Design Institute (KMDI) where it had originated. A business plan and a budget had to be developed and approved.

The next steps were to develop a set of legal documents that formalized the "UofT community source" arrangements under which all the source code would be shared among consortium members. At present the entire ePresence infrastructure is available to consortium members under the UofT community source license until we complete the last step in our release, choosing an appropriate license for the open-source release of the core technology.

Open-source development is distributed and bottom-up, and is controlled as much by individual initiative, reputation, and shared values as it is by the occasional charismatic leader such as Linus Torvalds [15]. The challenge is to produce high-quality, well-structured, readable, and reliable code despite the distributed nature of software development.

Linux (or, strictly speaking, GNU/Linux) began as two individual Herculean efforts of individuals with remarkable wisdom, insight, and skill---Richard Stallman and Linus Torvalds. Torvalds especially was successful in attracting a worldwide community of passionate and skillful developers who were able to form a community that generally functioned effectively and harmoniously. Many more recent open-source developments began from or have been sponsored by corporations or occasionally now even universities. Nonetheless, the challenge is to stimulate and nurture a willingness of numerous far-flung individuals to participate in a collective effort.

Our goal is to form a distributed synergistic development community with shared values. We shall promote communication among members of this emerging community by supporting listservs and blogs. Training and support is available to consortium members using ePresence media that are visual explanations of ePresence [1]; the first annual ePresence User's Group meeting is planned for 2006. All contributed code proposed for inclusion in ePresence will be reviewed. A shared context will be established through the use of bug reporting and feature request mechanisms.

We are currently involved in a recently established open-source initiative, Project Open Source Open Access (Project OS|OA) at the University of Toronto's Knowledge Media Design Institute ( Project OS|OA is working collaboratively with the Canadian Internet Policy and Public Interest Clinic (CIPPIC) at the University of Ottawa to develop a toolkit to aid in the licensing of university technology as open source. The Open Source Software Licensing Primer, developed by Marcus Bornfreund, is the first item in the toolkit.

Soon to be added to the toolkit will be the results of a survey being conducted of major North American universities to see to what extent they are releasing software and other educational multimedia using open-source strategies and what approach they are taking to the four issues of technology, community, legal framework, and business model (an early version of this report is Hoss, 2005).


ePresence technology development is ably led by system architect and chief programmer Peter Wolf, aided by a significant number of researchers and students. Thanks also to Dr. Gale Moore, director of KMDI, for her contributions to the project. We gratefully acknowledge our research sponsors the Natural Sciences and Engineering Research Council of Canada and the Bell University Laboratories of the University of Toronto.


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