    Network Working Group                                     Tom O'Sullivan
    Request for Comments: 313                                       Raytheon
    NIC: 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 INSTRUCTION

    INTRODUCTION

       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 student

    O'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 1972

    LANGUAGE 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 requires

    O'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, is

    O'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 Hélène Morin, Viagénie 10/99]

    O'Sullivan                                                      [Page 8]