The Learning Resource Server (LRS) is a suite of information servers that form multiple realizations of a distributed learning network. We have adopted a publishing metaphor as a framework for constructing resources for the LRS. This Distributed Authoring Information Server (DAISy) model is based on the notion that all members in a learning community can participate in the construction of knowledge resources. Consequently, the LRS represents a "shared knowledge space", where distributed communities can exchange instructional resources. Parallel to the DAISy model is the concept of Network Media, which defines the visual, animated and audio resources presented and supported by a client-server environment. A media specialist facilitates multimedia publishing on the LRS and mentors authors who are interested in producing such resources. In this presentation, the roles of the LRS, DAISy, and Network Media will be discussed in the context of a Teaching TeleApprenticeship.
In this way, the server is centralized in how it is maintained, but it is decentralized in how information is shared and constructed. The DAISy model relies on client-server technologies. The server is the "publishing" agent, and the client software is the "authoring" agent. The negotiation of who or what gets published depends on the structure of the learning community. The net result is that the LRS reflects the work of many people working either singularly, or in collaboration on the LRS.
Networked media can serve to supplement the exchange of knowledge within a community of learners. On the LRS server, the dominant use of digital images is to identify those publishers and authors associated with specific communities. For example, many of our technology courses have developed documents which include individualized digital images of all class members. Because most communication is exchanged electronically, students can access these images to identify with whom they are electronically communicating. Likewise, digital images are used to contextualize many of our projects and ideas. For example, images from the TTA Noon Project help the many international participants verify the correct procedures. More broadly, other authors have chosen to use images to carry the overall message of a particular event in time. An example is found with the CUSeeMe exchange between a University of Illinois class and a class from the University of Twente in the Netherlands. Unlike textual description of such events, visual media capture a moment in time which will never be specifically relived.
The most recent addition to our server is digital video. We've defined server mediated digital video as Networked Video. Because of the dimensions of Networked Video, great care is given to the production and use of this media. We have defined the dimensions of Networked Video in terms of size, time, expertise, platform, and user preference.
Size and Time: When considering Networked Video, the size of the file effects the transfer speed and the ability of users to playback the given file. The larger the file, the longer it will take for the data to be transmitted properly and the more space needed on the end users hard drive. On a wide-area network, a 160x120 2 minute, well produced video file will take approximately 8-10 MB of space and about 1-2 minutes to transfer each megabyte of data. The size of the file is also dependent on the presentation window frame. Standard window sizes range from 640x480, 340x280 and 160x120 with the former being less practical and the latter being the most practical. A 160x120 frame is more than adequate to convey general information.
Expertise: Not every author will have the expertise to produce video and image files. There needs to be at least one person who specialized in the production of these files. The Networked Media specialist could then mentor others. However, the expense involved with most media production is often a deterring factor in the high use of digital video. But, this individual could also look at low cost ways to produce the media. Cost also factors into the ability to purchase necessary software as well as multiple copies of the software. For this reason, it is necessary to have at least one individual, the expert, who will make use of the software. While it is not imperative, it would help if this Networked Media specialist is familiar with analog video taping and production.
Platform: Because the Internet reaches both Mac and PC desktop platforms and Unix workstations, it is necessary to ensure that the files are cross-platform. Most production software will allow this as an option.
User Preference: Because there is no way to know what the user prefers, it behooves authors to ensure that their message can be conveyed not only by the media, but by text as well. This allows the user to chose what media most adheres to his/her machine and time constraints as well as preference.
These dimensions advance the opportunities for collaboration on projects and for a multiple interpretation of an intended message. A picture can describe what words may lack, but text can fill-in what was not captured at a specific moment. Networked Media is a slave to technological innovations. Therefore, constraints often disappear over time.
Secondly, the LRS provides a medium for peripheral participation by novices as they gain expertise in their domain. For example, students using server-mediated course resources, such as the SATEX course folder, can review previous SATEX courses which are archived on the server. Peripheral novices can also begin constructing their own resources through interaction with their LRS sponsor or media specialist with little expertise with the Internet.
Third, the LRS is the cornerstone of a distributed network learning environment, in which a community can collaborate on personal or shared goals. The LRS provides personal and shared knowledge spaces using various client-server technologies.