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Network Working Group                                     Tom O'SullivanRequest for Comments: 313                                       RaytheonNIC: 9343                                                  March 6, 1972(CBI: 1)                       COMPUTER BASED INSTRUCTION   Current development of Computer Based Instruction (CBI) systems seem   to be directed toward two types of system:      1.)  Small to medium scale, dedicated, stand alone systems (such      as the IBM 1130, 1500, 1800 complexes) or medium scale systems      with dedicated network implications (such as TICKET), and      2.)  Large, centralized, dedicated systems with dedicated network      implications (such as PLATO).   Some attention has been given to the application of the resources of   a General Purpose Computer Network to CBI (e.g., the EDUCOM efforts),   however the full implication of the use of such resources do not   generally seem to be understood by either the CBI development centers   (at academic institutions or at the Armed Forces training or   development centers), where most of the current activity takes place,   or at ARPA Network Nodes, where most of the resources reside.   This Request For Comment has two purposes  To:      1.)  Solicit comments from the Network Working Group, and others,      on how selected classes of (and what specific) resources of a      General Purpose Network might be applied to the field of Computer      Based Instruction and      2.)  Initiate a dialog between interested parties on the problems      of Computer Based Instruction, not limited to, but including, the      uses of General Purpose Computer Network resources.   The attached paper discusses some of the applications of the   resources of a large General Purpose Network to computer Based   Instruction systems.  Response and discussion are encouraged through   the NIC system.O'Sullivan                                                      [Page 1]

RFC 313                Computer Based Instruction             March 1972                   GENERAL PURPOSE COMPUTER NETWORKS                                    AND                        COMPUTER BASED INSTRUCTIONINTRODUCTION   A high level of Computer Based Instruction (CBI) activity exists both   in the academic and armed service communities, with the promise of a   substantial amount of early development of instruction courses and   instructional management facilities.  The major functional areas of   interest can be described as follows:      1.)  Design and Development      2.)  Field Tests      3.)  Distribution and Operational Use      4.)  Evaluation and Modification   Specific computer support requirements are function of the philosophy   and reflected strategy of implementation for each of the functional   areas of interest.  Design and development activities may focus on   overall curriculum development or on specific training or educational   goals involving a specific course.  The focus of attention will have   an effect on the support requirements, e.g., the type and size of   data base, specialized processing capabilities, etc.  Support   requirements for Field Tests will be a function of whether they are   to be performed at a central location, or are geographically   distributed, particularly with respect to data collection procedures,   computer support and terminal clusters, and communications.   Solutions to the problems of the distribution and operational use of   CBI systems and programs will be a function of the extent to which   the training activity is proliferated (i.e., geographically or   organizationally distributed).  Both the level of activity, and the   solution to problems, in the area of Evaluation and Modification will   depend on the goals of the instructional process, the extent of   dynamic change in the technology or specific application involved,   and the degree to which the course(s) developed meet the needs for   which they were intended.   The above discussion has a heavy emphasis on Computer Aided   Instruction (CAI) component of CBI, where the computer is directly   used in the instructional process for lesson presentation, test,   drill and practice, etc.  Another component of CBI, Computer Managed   Instruction (CMI), uses the computer as a management tool to guide   the instructional process.  CMI may be used in conjunction with CAI,   or as an aid in guiding instructional processes of a more traditional   nature.  CMI, in addition to providing assistance in student   selection, scheduling, and followup on past course performance, may   provide guidance to instructors in the form of diagnostics of studentO'Sullivan                                                      [Page 2]

RFC 313                Computer Based Instruction             March 1972   weaknesses, prescriptions for strengthening student understanding,   and guidance in the redirection of students.  In addition, CMI can   provide management with evaluations of course and instructor   effectiveness.  CMI has corollaries to the discussion of CAI resource   requirements and their relation to the philosophy and related   strategy employed.   Bearing in mind the effects on resource requirements of the complex   considerations involved in CBI, there seem to be several areas in   which the resources of a large General Purpose Computer Network, such   as the ARPA Network, could be of high utility if properly applied.   These include:      1.)  The Network itself      2.)  Centralized Data Storage      3.)  Language processors      4.)  Dialogue Support Systems   As questions of philosophy and general strategy are resolved, or   assumed, the hard questions of implementation come into play.   Tradeoffs between competing approaches of the instructional strategy   or model, techniques of measurement, languages, hardware, etc., must   be made.  It appears that both in resolving the tradeoffs, and in the   implementation stage, network resources could prove to have high   utility.THE NETWORK   The network itself seems to have utility for CBI that goes beyond the   function of providing a communications base for linking terminal(s)   (individual or clustered) to processors dedicated to CBI.   The latter function, however, is important.  The communications   network exists, and can be tied into efficiently from many parts of   the country.  If there were dedicated CBI systems on the network, it   would facilitate:      1.)  Evaluation of a single system (or its several components) for      adequacy, or of competing systems for relative utility, by an      interested user center, to assist in the selection of a system for      a specific use;      2.)  Early use by a geographically isolated user center, through      use of clustered terminals, of the full power of a major CBI      center,O'Sullivan                                                      [Page 3]

RFC 313                Computer Based Instruction             March 1972         a.)  For a continuing period of low level use, or         b.)  Building over time until total usage by the isolated         center justifies the installation of a full CBI center of its         own.   Existing network resources also hold promise of utility.  Many   manufacturers' systems, with associated varieties of operating system   software, are available on the ARPA Network.  Within most of these, a   variety of application software is available, some supporting CBI and   data base applications.  Therefore, even without the presence of a   dedicated CBI system available as a service center on the network,   use could be made in support of CBI interests.      1.)  Testing of existing language and data base systems for      appropriateness to CBI problems.      2.)  Development of CBI systems or components for demonstration      and/or test.      3.)  Testing of existing courses, lessons, or lesson segments to      determine if they meet specified performance criteria, eliminating      potential duplication of course development effort.      4.)  Development of CBI systems to be operated under a specific      set of hardware and software resources available in the network in      anticipation of delivery of a dedicated operational system.      5.)  Greater flexibility in selection of test sites for field test      of courses developed, and performance of those tests prior to the      delivery of operational hardware.      6.)  Formalization of hardware support and associated software      protocols to clustered terminals to provide continuing service to      geographically remote training activities.   Even the interests of dedicated CBI systems can be served, since the   network has established communications and terminal support protocols   that could tend to reduce the software efforts required to establish   contact between a large dedicated service center, and clusters of   user center terminals.  In addition, terminal types not normally   supported by the CBI service center machine might be accommodated by   accessing the network through a compatible port, and getting into the   service center through established network protocols.O'Sullivan                                                      [Page 4]

RFC 313                Computer Based Instruction             March 1972   Terminal access to the ARPA Network could be provided in the   following ways:      1.)  Single Terminals - over common carrier facilities to the      nearest compatible HOST or TIP.      2.)  Large Clusters - Simple single purpose TIP, or simple mini-      computer supported in the network as far distant HOST.      3.)  Small clusters - either of the above two depending on the      length and intensity of expected use and the number or terminals      in the cluster.   In addition to the above general uses of a large General Purpose   Computer Network, there are several specific classes of network   resources that may be useful.CENTRALIZED DATA STORAGE   The effect of economy of scale could reduce costs for smaller CBI   systems if they make use, through the network, of mass storage on   larger systems.  If duplicate smaller systems are distributed in the   field, then the centralized storage would have a multiplying effect   on savings for lessons and lesson material, but special attention   would have to be given to the file structure to permit efficient use   of look ahead techniques for lessons, lesson segments, and individual   student pages.   For CMI data there are savings that go beyond the economy of scale.   A single management system could be selected or built on a large   service center machine to be used by CBI systems on the network, even   though the operational CBI systems are supported by different   manufacturers' hardware.  This would not only reduce the cost for   programming and maintaining CMI systems, but also facilitate cross   system analysis and intersystem comparison, even though each using   system would have its own set of files.  The user of the network data   reconfiguration service and data transfer protocol should make such   operations feasible.   This approach to CMI would assist in early development stages of   course material by easing the problem of accessing data on past   performance and norms.  In the case of geographically distributed   testing, the evaluation team would have faster access to performance   data.  Both the distribution and modification tasks seem cleaner   since there is only one copy of the released version to be updated.   If the trillion bit laser memory proposed for AMES becomes a reality,   then the economy of scale argument can be expected to be dramatic.O'Sullivan                                                      [Page 5]

RFC 313                Computer Based Instruction             March 1972LANGUAGE PROCESSORS   A basic characteristic of a large General Purpose Computer Network is   that it is capable of providing support from various manufacturers'   machines.  That is, such a network can be comprised of a number of   special purpose processors that can be distributed geographically and   organizationally to locations where the best support exists for each   process.   This characteristic makes it possible to select and join the best   match of capabilities for a complex application .  It is no longer   necessary to settle for a hardware/software system that does a   reasonable job in most areas of the applications need.   CBI is a complex application.  In addition to a good management   system and associated data base, it requires heavy text handling for   lesson material, table lookup and branching logic for acting on the   student selected answers to multiple choice questions, a student   arithmetic problem solving language for drill and practice,   simulation capability of both physical processes (for laboratory and   circuit simulation), and of decision processes (for gaming   experience), and a future need for natural language processors to   permit evaluation of free form student responses.  In addition, there   may be need for heavy statistical and arithmetic processing for   course, student, and instructor evaluation.   Depending on the course, various mixes of languages to support the   above activities will be needed.  Some believe that the language   required for presentation of course material and evaluation of   student response (and associated appropriate action) may be heavily   dependent on the type of course being given.  As we develop a deeper   understanding of the learning process, we are likely to require   expansion of languages to provide new functions and perform processes   not yet identified.   To provide expandability of languages, Meta-compiler techniques can   be applied.  Meta-compilers are in an early stage of development;   however, several are available on the network.  In addition to   facilitating language expansion with minimum effort while preserving   the workability of code written in the previous versions of the   changing language, the Meta-compiler can be made to produce either   compiler or program object code that will operate on several   different target machines.  This feature can give both programs and,   in some cases, compilers that are transportable across machines,   eliminating the need to settle on a single manufacturer's hardware   when it is expected that a CBI compiler or interpreter, or a course   or set of courses is going to be used in a way that requiresO'Sullivan                                                      [Page 6]

RFC 313                Computer Based Instruction             March 1972   substantial geographic distribution.  Hardware decisions can be based   on the most cost-effective hardware for the combinations to be run at   one time.   Use of Meta-compilers will permit the development and debugging of   new course material in advance of the delivery of the system selected   for operations, even though the selected machine is not yet   represented in the large General Purpose Computer Network.  Field   test can also proceed before the selected hardware arrives.   Experience to date in the use of Meta-compilers indicates that the   use of their high order languages to implement compilers and   interpreters result in dramatic savings in both turnaround time and   the absolute cost of producing a finished language product.DIALOGUE SUPPORT SYSTEMS   In a field developing as rapidly as CBI, and at a time when   substantial implementation is about to take place, dialogue between   theoreticians, developers, and users is an important issue.  New   tools for supporting dialogue among members of a distributed group   are currently in experimental use in the ARPA network.  These new   techniques not only support dialogue more rapidly than the   distribution of papers, notes, and memos, but in some cases tend to   sharpen the thought process and yield a better result.   The application of such facilities, when ready, will be helpful   beyond the early planning stages or projects.  After plans are set,   during the development of a project, a broader group of experts will   be able to be called on to work on problems and questions as they   occur.  Later, as the product is being field tested (especially if   testing is distributed or separated from the evaluation group), these   new tools can be used to allow the test implementors to interact with   each other and with evaluators in a more timely manner than a post-   mortum meeting, resolving problems and questions as they occur, and   as a side benefit producing more complete documentation of test   progress.   After the tests, when the product is being used operationally, these   same tools can provide an excellent vehicle for tapping the ideas,   suggestions, and enrichments contributed by the more creative   instructors, and facilitate acting on them more rapidly than is   currently possible.   Meanwhile, as these tools are being developed, present ARPA Network   procedures for supporting the dialogue in a distributed group in more   traditional ways may prove helpful.  The Network Information Center   (NIC), in addition to supporting the general ARPANET community, isO'Sullivan                                                      [Page 7]

RFC 313                Computer Based Instruction             March 1972   supporting special interest groups such as the Speech Understanding   Research (SUR) group.  The application of these procedures could   establish a valuable link between the academic-nonprofit institutions   working on CBI, the centers in the Armed Forces where development and   operations are taking place, and members of the network community who   have an intimate understanding of the network resources available.CONCLUSION   This paper has argued that there are resources in a large General   Purpose Computer Network that can be applied to CBI with high   utility.  The argument can be extended to suggest that large   dedicated CBI systems can have greater utility to users (and in the   other direction, greater use), if tied into a General Purpose   Computer Network, with respect to current network capabilities,   future network developments, and in some cases provide backup during   periods of overload or system failure.   There are certainly important CBI issues outstanding in areas of   pedagogy, strategy, curriculum development, testing, etc.  As CBI   systems are developed there are important issues of control (of the   development process, of the distribution of material, and of   modification of those materials).  However, these issues seem to be   independent of the question of whether CBI takes advantage of the   resources of a large General Purpose Network.   There are important problems to be solved on the computer side   dealing with better tools to handle and evaluate masses of data,   language, and protocols for network utilization.   However, there seems to be sufficient promise in what we know of   present network capabilities to warrant serious consideration by the   developers of CBI of how General Purpose Networks fit in, and by   network people of how their resources apply to this important large   application area.        [This RFC was put into machine readable form for entry]     [into the online RFC archives by H�l�ne Morin, Viag�nie 10/99]O'Sullivan                                                      [Page 8]