SCORM rd EDITION Sharable Content Object Reference Model

Transcription

1 SCORM rd EDITION Sharable Cntent Object Reference Mdel Run-Time Envirnment NOVEMBER 16, 2006 VERSION Advanced Distributed Learning. All Rights Reserved.

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3 Advanced Distributed Learning (ADL) SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 Available at ADLNet.gv Fr questins and cmments visit Ask The Experts at ADLNet.gv SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 i

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5 Chief Technical Architect Philip Ddds Technical Editr Schawn E. Thrpp Acknwledgements ADL wuld like t thank the fllwing rganizatins and their members fr their cntinued cmmitment t building interperable e-learning standards and specificatins: Alliance f Remte Instructinal Authring & Distributin Netwrks fr Eurpe (ARIADNE) ( Aviatin Industry CBT Cmmittee (AICC) ( Institute f Electrical and Electrnics Engineers (IEEE) Learning Technlgy Standards Cmmittee (LTSC) ( IMS Glbal Learning Cnsrtium, Inc. ( ADL wuld als like t thank the ADL Cmmunity fr their cmmitment and cntributin t the evlutin f SCORM. SCORM rd Editin dcumentatin suite reprinted with permissin frm IEEE Std IEEE Standard fr Learning Technlgy Data Mdel fr Cntent t Learning Management System Cmmunicatin, Cpyright 2004, by IEEE; IEEE Std IEEE Standard fr Learning Technlgy ECMAScript Applicatin Prgramming Interface fr Cntent t Runtime Services Cmmunicatin, Cpyright 2003, by IEEE; IEEE Std IEEE Standard fr Learning Object Metadata, Cpyright 2002, and IEEE Std IEEE Standard fr Learning Technlgy Extensible Markup Language (XML) Schema Definitin Language Binding fr Learning Object Metadata, Cpyright 2005, by IEEE. The IEEE disclaims any respnsibility r liability resulting frm the placement and use in the described manner. SCORM rd Editin dcumentatin suite reprinted with permissin frm IMS Cntent Packaging v1.1.4 Cpyright 2004, by IMS Glbal Learning Cnsrtium Inc. and IMS Simple Sequencing v1.0 Cpyright 2003, by IMS Glbal Learning Cnsrtium Inc. IMS Glbal Learning Cnsrtium has made n inquiry int whether r nt the implementatin f third party material included in this dcument wuld infringe upn the intellectual prperty rights f any party. Recipients f this dcument are requested t submit, with their cmments, ntificatin f any relevant patent claims r ther intellectual prperty rights f which they may be aware that might be infringed by any implementatin f the dcument set frth in this dcument, and t prvide supprting dcumentatin t IMS. This material is being ffered withut any warranty whatsever, and in particular, any warranty f nn-infringement is expressly disclaimed. Any use f this material shall be made entirely at the implementer s wn risk, and neither the IMS Glbal Learning Cnsrtium, nr any f its members r submitters, shall have any liability whatsever t any implementer r third party fr any damages f any nature whatsever, directly r indirectly, arising frm the use f this material. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 iii

6 COPYRIGHT Cpyright 2006 Advanced Distributed Learning (ADL). All rights reserved. DISTRIBUTION Permissin t distribute this dcument is granted under the fllwing stipulatins: 1. The use f this dcument, its images and examples is fr nn-cmmercial, educatinal r infrmatinal purpses nly. 2. The dcument, its images and examples are intact, cmplete and unmdified. The cmplete cver page, as well as the COPYRIGHT, DISTRIBUTION and REPRODUCTION sectins, are cnsequently included. REPRODUCTION Permissin t reprduce this dcument cmpletely r in part is granted under the fllwing stipulatins: 1. The reprductin is fr nn-cmmercial, educatinal r infrmatinal purpses nly. 2. Apprpriate citatin f the surce dcument is used as fllws: a. Surce: Advanced Distributed Learning (ADL), Sharable Cntent Object Reference Mdel (SCORM ) rd Editin Run-Time Envirnment Versin 1.0, Fr additinal infrmatin r questins regarding cpyright, distributin and reprductin, cntact: ADL C-Labratry Hub 1901 Nrth Beauregard Street, Suite 600 Alexandria, Virginia USA iv SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

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8 Table f Cntents SECTION 1 THE SCORM RUN-TIME ENVIRONMENT (RTE) INTRODUCTION TO THE SCORM RUN-TIME ENVIRONMENT (RTE) BOOK What is Cvered in the SCORM RTE Bk? Using the SCORM RTE Bk Relatinship with ther SCORM Bks RUN-TIME ENVIRONMENT OVERVIEW SECTION 2 MANAGING THE RUN-TIME ENVIRONMENT (RTE) RUN-TIME ENVIRONMENT (RTE) MANAGEMENT T Run-Time Envirnment Tempral Mdel Launching Cntent Objects Taking Cntent Objects Away SECTION 3 APPLICATION PROGRAMMING INTERFACE (API) APPLICATION PROGRAMMING INTERFACE (API) API Overview API Methds and Syntax Sessin Methds Data-Transfer Methds Supprt Methds Cmmunicatin Sessin State Mdel API Implementatin Errr Cdes LMS RESPONSIBILITIES API Instance SCO RESPONSIBILITIES Finding the API Instance API Usage Requirements and Guidelines SECTION 4 SCORM RUN-TIME ENVIRONMENT DATA MODEL DATA MODEL OVERVIEW SCORM Run-Time Envirnment Data Mdel Basics SCORM RUN-TIME ENVIRONMENT DATA MODEL Data Mdel Versin Cmments Frm Learner Cmments Frm LMS Cmpletin Status Cmpletin Threshld Credit Entry Exit Interactins Launch Data Learner Id Learner Name Learner Preference Lcatin Maximum Time Allwed Mde Objectives Prgress Measure Scaled Passing Scre vi SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

9 Scre Sessin Time Success Status Suspend Data Time Limit Actin Ttal Time APPENDIX A ACRONYM LISTING... A-1 ACRONYM LISTING... A-3 APPENDIX B REFERENCES...B-1 REFERENCES...B-3 APPENDIX C DOCUMENT REVISION HISTORY...C-1 DOCUMENT REVISION HISTORY...C-3 List f Figures Figure 1.1a: The SCORM Run-Time Envirnment Bk as Part f the SCORM Bkshelf Figure 1.2a: SCORM Cnceptual Run-Time Envirnment Figure 2.1a: Cnceptual Cntent Structure Illustratin Figure a: Single Learner Attempt with ne Learner Sessin Figure b: Learner Attempt Spread Over Several Learner Sessins Figure c: Successive Learner Attempts, Spread Over Several Learner Sessins Figure 3.1.1a: Illustratin f API, API Instance and API Implementatin Figure 3.1.6a: Cnceptual API Instance State Transitins Figure 3.2.1a: Permitted DOM Lcatins f an API Implementatin Figure 3.3.1a: Illustratin f Finding the API Figure 4.1.1a: Illustratin f Using the Data Mdel with the API Figure 4.2.9a: Interactins and Interactin Data SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 vii

10 List f Tables Table: 3.1.1b: Categries f API Methds Table 3.1.7a: Errr Cde Categries and Range Table a: Reserved Prperty Delimiters Table b: Reserved Separatr Delimiters Table 4.2a: SCORM Run-Time Envirnment Data Mdel Elements Summary Table 4.2b: Data Mdel Element Table Explanatin Table 4.2.1a: Dt-ntatin Binding fr the Data Mdel Versin Data Mdel Element Table 4.2.2a: Dt-ntatin Binding fr the Cmments frm Learner Data Mdel Element Table 4.2.3a: Dt-ntatin Binding fr the Cmment frm LMS Data Mdel Element Table 4.2.4a: Dt-ntatin Binding fr the Cmpletin Status Data Mdel Element Table a: GetValue() Evaluatin f Cmpletin Status Table 4.2.5a: Dt-ntatin Binding fr the Cmpletin Threshld Data Mdel Element Table 4.2.6a: Dt-ntatin Binding fr the Credit Data Mdel Element Table 4.2.7a: Dt-ntatin Binding fr the Entry Data Mdel Element Table 4.2.8a: Dt-ntatin Binding fr the Exit Data Mdel Element Table 4.2.9a: Dt-ntatin Binding fr the Interactins Data Mdel Element Table a: Crrect Respnse Pattern Frmat Requirements Table a: Learner Respnse Frmat Requirements Table a: Dt-ntatin Binding fr the Launch Data Data Mdel Element Table a: Dt-ntatin Binding fr the Learner ID Data Mdel Element Table a: Dt-ntatin Binding fr the Learner Name Data Mdel Element Table a: Dt-ntatin Binding fr the Learner Preference Data Mdel Element Table a: Dt-ntatin Binding fr the Lcatin Data Mdel Element Table a: Dt-ntatin Binding fr the Max Time Allwed Data Mdel Element Table a: Dt-ntatin Binding fr the Mde Data Mdel Element Table a: Mde and Credit Values Table a: Scenaris fr String Cllectin Data Table a: Dt-ntatin Binding fr the Objectives Data Mdel Element Table a: Prgress Measure relatinship with Cmpletin Status Table b: Dt-ntatin Binding fr the Prgress Measure Data Mdel Element Table a: Dt-ntatin Binding fr the Scaled Passing Scre Data Mdel Element Table a: Dt-ntatin Binding fr the Scre Data Mdel Element Table a: Dt-ntatin Binding fr the Sessin Time Data Mdel Element Table a: Dt-ntatin Binding fr the Success Status Data Mdel Element Table a: GetValue() Evaluatin f Success Status Table a: Dt-ntatin Binding fr the Suspend Data Data Mdel Element Table a: Dt-ntatin Binding fr the Time Limit Actin Data Mdel Element Table a: Dt-ntatin Binding fr the Ttal Time Data Mdel Element viii SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

11 SECTION 1 The SCORM Run-Time Envirnment (RTE) Frm IEEE Std IEEE Standard fr Learning Technlgy Data Mdel fr Cntent t Learning Management System Cmmunicatin, Cpyright 2004 IEEE; IEEE Std IEEE Standard fr Learning Technlgy ECMAScript Applicatin Prgramming Interface fr Cntent t Runtime Services Cmmunicatin, Cpyright 2003 IEEE; IEEE Std IEEE Standard fr Learning Object Metadata, Cpyright 2002 IEEE; and IEEE Std IEEE Standard fr Learning Technlgy Extensible Markup Language (XML) Schema Definitin Language Binding fr Learning Object Metadata, Cpyright 2005 IEEE. All rights reserved. Frm IMS Cntent Packaging v1.1.4 Cpyright 2004, by IMS Glbal Learning Cnsrtium Inc. and IMS Simple Sequencing v1.0 Cpyright 2003, by IMS Glbal Learning Cnsrtium Inc. All rights reserved. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-1-1

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13 1.1. Intrductin t the SCORM Run-Time Envirnment (RTE) Bk The Sharable Cntent Object Reference Mdel (SCORM ) is ften described as a set f bks n a bkshelf. The Run-Time Envirnment (RTE) bk is ne f a set f bks (refer t Figure 1.1a: The Run-Time Envirnment Bk as Part f the SCORM Bkshelf). Mre infrmatin n the ther SCORM bks and their relatinships t ne anther can be fund in the SCORM 2004 Overview. The SCORM RTE bk describes the Learning Management System (LMS) requirements in managing the run-time envirnment (i.e., cntent launch prcess, standardized cmmunicatin between cntent and LMSs and standardized data mdel elements used fr passing infrmatin relevant t the learner s experience with the cntent). The RTE bk als cvers the requirements f Sharable Cntent Objects (SCOs) and their use f a cmmn Applicatin Prgramming Interface (API) and the SCORM Run-Time Envirnment Data Mdel. Figure 1.1a: The SCORM Run-Time Envirnment Bk as Part f the SCORM Bkshelf What is Cvered in the SCORM RTE Bk? There are several key cncepts that are intrduced in the SCORM RTE bk. The bk cvers the essential LMS respnsibilities fr sequencing cntent bjects (SCOs r Assets) during run-time and allwing SCOs t indicate navigatin requests. In additin, guidance is ffered fr prviding navigatin cntrls t learners. General subjects discussed include: RTE Management: Launching f cntent bjects SCOs and Assets, Management f cmmunicatins with a SCO, Run-time envirnment data mdel management SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-1-3

14 Applicatin Prgramming Interface (API): LMS API requirements, SCORM cmmunicatin requirements, cmmunicatin errr cnditins SCORM Run-Time Envirnment Data Mdel: Data mdel management and behavir requirements, Data type requirements Using the SCORM RTE Bk This bk shuld prve useful t LMS, SCO and authring tl vendrs wishing t supprt SCORM in their prducts, and t anyne wishing t understand the cmmunicatins relatinship between cntent and LMSs, such as SCORM cntent develpers. Sectin 1: The SCORM Run-Time Envirnment (RTE) and Sectin 2: Managing the Run-Time Envirnment (RTE) f this bk cver general RTE-related cncepts. These sectins are recmmended reading fr thse seeking an intrductin t the cncepts behind the SCORM RTE and wh may nt wish t delve int its technical details. Others wh may find these sectins useful include thse wishing t learn abut updates t the RTE. Sectin 2.1: Run-Time Envirnment (RTE) Management, fr instance, discusses hw the new Sequencing and Navigatin bk impacts the SCORM RTE. Sectin 3: Applicatin Prgramming Interface (API) is the first sectin prviding technical details abut the RTE. This sectin explains every SCORM API methd and errr message available t cntent develpers, and even prvides sample cde as well as API Usage Requirements and Guidelines. Sectin 4: SCORM Run-Time Envirnment Data Mdel cvers every SCORM data mdel element in detail, which includes a listing f specific LMS and SCO behavir requirements in relatin t a given element Relatinship with ther SCORM Bks While the varius SCORM bks are intended t stand alne, there are areas f verlap r mutual cverage. Fr instance, while this bk fcuses primarily n cmmunicatin between learning cntent and LMSs, it frequently refers t SCOs that cnduct that cmmunicatin. SCOs are discussed in sme detail in the SCORM Cntent Aggregatin Mdel (CAM) bk. Similarly, while the SCORM Sequencing and Navigatin (SN) bk cvers the details f SCORM sequencing and navigatin prcesses, including detailed cverage f hw an LMS evaluates navigatin requests and related activities, this bk deals with cntent delivery, and as such, lightly tuches n hw an LMS determines which piece f cntent t deliver at any given time. RTE-1-4 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

15 The SCORM Cntent Aggregatin Mdel (CAM) Bk The SCORM CAM bk [18] defines respnsibilities and requirements fr building cntent aggregatins (i.e., the prcess f assembling, labeling and packaging cntent). The bk cntains infrmatin n creating cntent packages, applying metadata t the cmpnents in the cntent package and applying sequencing and navigatin details in the cntext f a cntent package. Several dependencies span frm the SCORM CAM bk t the SCORM RTE bk. Metadata is data abut data. Metadata can be used t describe the different cmpnents f the SCORM cntent mdel (Cntent Aggregatins, Cntent Organizatins, Activities, SCOs and Assets). Metadata, a frm f labeling, enhances search and discvery f these cmpnents. At this time, there are n defined relatinships between metadata and the SCORM Run-Time Envirnment Data Mdel. Fr these reasns, metadata is nt discussed in detail in the SCORM RTE bk. This relatinship may change as SCORM evlves. A Cntent Package, in a general sense, bundles cntent bjects with a cntent structure that is described by a manifest. A SCORM Cntent Package may represent a SCORM curse, lessn, mdule r may simply be a cllectin f related cntent bjects that may be stred in a repsitry. The manifest, an essential part f all SCORM Cntent Packages, is cntained in an Extensible Markup Language (XML)-based file named imsmanifest.xml. This file, similar in many ways t a packaging slip, describes the cntents f the package and may include an ptinal descriptin f the cntent structure. SCORM Cntent Packages may include additinal infrmatin that describes hw an LMS is intended t prcess the Cntent Package and its cntents. Sme f these elements are utilized by the SCORM RTE mdel. Cntent bject launch lcatins and launch parameters are als described as elements in a SCORM Cntent Package. These elements are essential t the launch and delivery f cntent bjects. The SCORM RTE bk details these elements and their effects n launching cntent bjects. Several elements in a SCORM Cntent Package affect initializatin and management f a cntent bject s run-time data mdel. The SCORM RTE bk details these data mdel elements and the required LMS behavirs. Other elements in a SCORM Cntent Package describe initial values fr specific elements f a cntent bject s run-time data mdel. The SCORM RTE bk details these data mdel elements and their initializatin behavir. When a SCORM Cntent Package includes a descriptin f cntent structure, sequencing infrmatin elements may be added t define an intended apprach t sequencing the package s cntent bjects. A SCORM Cntent Package may include User Interface (UI) elements that are intended t prvide guidance t an LMS n hw certain UI navigatin cntrls are t present, enabled r hidden. When a cntent bject is launched, as defined in this bk, these elements may be used, in cnjunctin with sequencing infrmatin (refer t the SCORM SN bk), t present the crrect (at the time f rendering) UI navigatin cntrls (e.g., Cntinue r Previus user interface cntrls). SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-1-5

16 Fr a better understanding f hw all f the elements described abve are specified in a SCORM Cntent Package, refer t the SCORM CAM bk The SCORM Sequencing and Navigatin (SN) Bk The SCORM SN bk is based n the IMS Simple Sequencing (SS) Specificatin [17], which defines a methd fr representing the intended behavir f an authred learning experience such that any SCORM cnfrmant LMS will sequence discrete learning activities cnsistently. The SCORM SN mdel defines hw the IMS SS specificatin is applied and it is extended in a SCORM envirnment. It defines the required behavirs and functinality that SCORM cnfrmant LMSs must implement t prcess sequencing infrmatin at run-time. Mre specifically, it describes the branching and flw f learning activities in terms f an Activity Tree, based n the results f a learner s interactins with launched cntent bjects and an authred sequencing strategy. An Activity Tree is a cnceptual structure f learning activities managed by the LMS fr each learner. The SCORM SN bk describes hw learner- and system-initiated navigatin events can be triggered and prcessed, resulting in the identificatin f learning activities fr delivery. Each learning activity identified fr delivery will have an assciated cntent bject. The SCORM RTE mdel describes hw identified cntent bjects are launched. The sequence f launched cntent bjects, fr a given learner and cntent structure, prvides a learning experience (learner interactin with cntent bjects); the SCORM RTE Mdel describes hw the LMS manages the resulting learning experience and hw that learning experience may affect the Activity Tree. RTE-1-6 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

17 1.2. Run-Time Envirnment Overview This bk defines the SCORM RTE mdel, which details the requirements fr launching cntent bjects, establishing cmmunicatin between LMSs and SCOs, and managing the tracking infrmatin that can be cmmunicated between SCOs and LMSs. In the cntext f SCORM, cntent bjects are either: SCOs, which cmmunicate during run-time, r Assets, which d nt cmmunicate during run-time. The SCORM RTE bk describes a cmmn cntent bject launch mechanism, a cmmn cmmunicatin mechanism between cntent bjects and LMSs, and a cmmn data mdel fr tracking a learner s experience with cntent bjects. These aspects create an envirnment where several f the ADL -ilities are satisfied. Fr example, cntent bjects that cmmunicate thrugh the standardized cmmunicatin mechanism can be mved frm LMS t LMS withut mdificatin t their cmmunicatin attempts; this increases learning bject prtability and durability, thereby lwering the cst f develpment, installatin and maintenance. The SCORM RTE defines a mdel that picks up at the pint when a specific cntent bject has been identified fr launch. The actual identificatin f the cntent bject t be launched is ut f scpe f this bk and can be fund in the SCORM SN bk [11]. This bk nly deals with the management f the run-time envirnment, which includes: The delivery f a cntent bject t the learner s Web brwser (i.e., launch); If necessary, hw a cntent bject cmmunicates with the LMS; and What infrmatin is tracked fr a cntent bject and hw the LMS manages that infrmatin. The fllwing sectins explain the relatinships between the SCORM RTE bk and the remaining SCORM bks. In additin, frequently used terminlgy will be intrduced at a high level t eliminate the need fr the reader t becme an expert in the entire SCORM t understand this bk. This, hwever, is nt an effective methd t learn and apply SCORM and its cncepts as a whle. It is strngly recmmended that each SCORM bk be read t mre fully understand the purpse, details, relatinships and advantages f all f the SCORM cncepts. SCORM was develped t enable the develpment f cntent bjects that are reusable and interperable acrss multiple LMSs. Fr this t be pssible, there must be a cmmn way t launch and manage cntent bjects, a cmmn mechanism fr cntent bjects t cmmunicate with an LMS and a predefined language r vcabulary frming the basis f the cmmunicatin. As illustrated in Figure 1.2a, these three aspects f the RTE are Launch, API and Data Mdel. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-1-7

18 Figure 1.2a: SCORM Cnceptual Run-Time Envirnment. The Launch prcess defines a cmmn way fr LMSs t start Web-based cntent bjects. The term cntent bject is used generically here t describe any piece f cntent that can be launched fr a learner. In SCORM, there are tw types f cntent bjects: SCOs and Assets. The launch prcess defines prcedures and respnsibilities fr the establishment f cmmunicatin between the launched cntent bject and the LMS. The cmmunicatin mechanism is standardized with a cmmn API. The API is the cmmunicatin mechanism fr infrming the LMS f the cnceptual cmmunicatin state between a cntent bject and an LMS (e.g., initialized, terminated and/r in an errr cnditin), and is used fr retrieving and string data (e.g., scre, time limits, etc.) between the LMS and the SCO. A Data Mdel is a standard set f data mdel elements used t define the infrmatin being tracked fr a SCO, such as the SCO s cmpletin status r a scre frm an assessment such as a quiz r a test. In its simplest frm, the data mdel defines data mdel elements that bth the LMS and SCO are expected t knw abut. The LMS must maintain the state f SCO s data mdel elements acrss learner sessins, and the SCO must utilize nly these predefined data mdel elements t ensure reuse acrss multiple systems. RTE-1-8 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

19 SECTION 2 Managing The Run-Time Envirnment (RTE) Frm IEEE Std IEEE Standard fr Learning Technlgy Data Mdel fr Cntent t Learning Management System Cmmunicatin, Cpyright 2004 IEEE; IEEE Std IEEE Standard fr Learning Technlgy ECMAScript Applicatin Prgramming Interface fr Cntent t Runtime Services Cmmunicatin, Cpyright 2003 IEEE; IEEE Std IEEE Standard fr Learning Object Metadata, Cpyright 2002 IEEE; and IEEE Std IEEE Standard fr Learning Technlgy Extensible Markup Language (XML) Schema Definitin Language Binding fr Learning Object Metadata, Cpyright 2005 IEEE. All rights reserved. Frm IMS Cntent Packaging v1.1.4 Cpyright 2004, by IMS Glbal Learning Cnsrtium Inc. and IMS Simple Sequencing v1.0 Cpyright 2003, by IMS Glbal Learning Cnsrtium Inc. All rights reserved. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-2-1

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21 2.1. Run-Time Envirnment (RTE) Management While the learner interacts with cntent bjects (the learning experience), the LMS evaluates learner perfrmance and navigatin requests (refer t the SCORM SN bk). When the LMS identifies an activity fr delivery t the learner, the activity has a cntent bject assciated with it. The LMS will launch the cntent bject and present it t the learner. Figure 2.1a depicts hw the cntent structure (rganizatin sectin f a manifest) can be interpreted in a tree (i.e., activity tree). The tree representatin is just a different way f presenting the cntent structure fund in the manifest (refer t the SCORM CAM bk). Figure 2.1a: Cnceptual Cntent Structure Illustratin A cmmn launch mdel addresses delivery f Web-enabled cntent bjects in the frm f SCOs and Assets within the cntext f a learning experience. This launch mdel enables cnsistency f cntent bject launch behavir acrss LMSs withut specifying the underlying LMS implementatin. In this cntext, the term LMS is used t describe any system that prvides the launch f cntent bjects. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-2-3

22 Run-Time Envirnment Tempral Mdel A learner becmes engaged with the cntent bject nce an activity with the assciated cntent bject (i.e., SCOs r Asset) has been identified fr delivery and the cntent bject has been launched in the learner s brwser-envirnment. Several key aspects need t be defined t aid in the tracking f the learner during the learning experience. The fllwing terms are defined by the Institute f Electrical and Electrnics Engineers (IEEE) Standard fr Learning Technlgy Data Mdel fr Cntent Object Cmmunicatin [1] and are referenced thrughut this dcument: Learner Attempt A tracked effrt by a learner t satisfy the requirements f a learning activity that uses a cntent bject. An attempt may span ne r mre learner sessins and may be suspended between learner sessins [1]. Learner Sessin An uninterrupted perid f time during which a learner is accessing a cntent bject [1]. Cmmunicatin Sessin An active cnnectin between a cntent bject (i.e., SCO) and an applicatin prgramming interface [1]. Lgin Sessin A perid f time during which a learner begins a sessin with a system (lgged n) until the time the learner terminates the sessin with the system (lgged ut). These fur terms are relevant when it cmes t managing the RTE fr a SCO. Fr an Asset, the RTE cnsists f nly independent learner attempts and learner sessins; ne learner attempt with a crrespnding learner sessin fr each launch f the Asset. The learner attempt begins nce an activity has been identified t be delivered (refer t the SCORM SN bk). During the attempt, the learner will be engaged with a cntent bject (either a SCO r Asset). Once the learner becmes engaged (cntent has been launched in the learner s Web brwser), a learner sessin begins. If the launched cntent bject is a SCO, as sn as the SCO initializes cmmunicatin with the LMS, a cmmunicatin sessin begins. A cmmunicatin sessin ends when the SCO terminates cmmunicatin with the LMS. Learner sessins can end leaving the SCO in a suspended state (the learner is nt thrugh with the SCO) r leaving the SCO in a nrmal state (the learner ended the learner attempt by meeting requirements defined by the SCO). Fr a SCO, the learner attempt ends when a learner sessin ends in a nrmal state. Fr an Asset, the learner attempt ends nce the Asset is taken away frm the learner. Figure 2.1.1a depicts the fur terms and their relatinships with ne anther fr a specific SCO. RTE-2-4 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

23 Figure 2.1.1a: Tempral Mdel Relatinships fr a Specific SCO Managing Learner Attempts and Learner Sessins A learner attempt is assciated with an imprtant LMS requirement defining the management f the set f run-time data mdel elements that the SCO may cmmunicate t the LMS. When a new learner attempt begins fr a SCO, the LMS is required t create and initialize a new set f run-time data fr the SCO t access and use (refer t Sectin 4: SCORM Run-Time Envirnment Data Mdel fr mre details). SCORM des nt specify exactly when the new set f run-time data is created, but all data mdel accesses must appear (t the SCO) as if they are being perfrmed n a new set f run-time data. What the LMS des with the previus attempt s data is utside the scpe f SCORM. The LMS may elect t stre this data fr histrical purpses r fr ther purpses such as reprting, auditing, diagnstic r statistical. The LMS may elect t discard any run-time data cllected during the previus attempt. The LMS is nly required t keep run-time data fr the learner attempt if the learner attempt was suspended. SCORM des nt specify any LMS requirements n the persistence r access t previus learner attempt data. Hwever, if the learner sessin is suspended, hence causing the learner attempt t be incmplete (i.e., suspended), the LMS is respnsible fr ensuring that any run-time data that was set prir t the suspensin is available when the next learner sessin fr the SCO begins; that is, the next time the (suspended) learning activity assciated with the SCO is identified fr delivery, the previus learner attempt is resumed and the run-time data frm the previus learner attempt is prvided in a new learner sessin. The fllwing figures ( a, b and c) illustrate several different relatinships between a learner attempt and learner sessin(s). Figure a illustrates a single learner attempt being accmplished with ne learner sessin. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-2-5

24 Figure a: Single Learner Attempt with ne Learner Sessin Figure b illustrates a single learner attempt spread ver several learner sessins. These sessins have been suspended and the learner attempt has been subsequently resumed until a learning sessin ends in a nrmal state. Figure b: Learner Attempt Spread Over Several Learner Sessins Figure c illustrates successive learner attempts. Within each f these learner attempts, any number f learner sessins may take place. Figure c: Successive Learner Attempts, Spread Over Several Learner Sessins RTE-2-6 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

25 Launching Cntent Objects As described in the SCORM CAM [18], the SCORM Cntent Mdel is made up f three cmpnents: Assets SCOs Cntent Organizatins The SCORM CAM bk describes the characteristics f launchable cntent bjects; SCOs and Assets are the defined cntent mdel cmpnents that can be launched. Different launching requirements exist depending n the cntent bject s type. The launching prcess defines the cmmn way fr LMSs t launch cntent bjects t the learner s Web brwser. The prcedures and respnsibilities fr establishing cmmunicatin between the launched cntent bject and the LMS vary depending n the type f the launched cntent bject. It is the respnsibility f the LMS t manage the sequencing between learning activities (refer t the SCORM SN bk) based n well-defined behavirs and the evaluatin f defined sequencing infrmatin applied t activities. The prgressin thrugh learning activities that cmprise a particular learning experience may be sequential, nnsequential, user-directed r adaptive, depending n the sequencing infrmatin defined and the interactins between a learner and cntent bjects. It is the respnsibility f the LMS (r sequencing cmpnent/service theref), based n sme navigatin event, t determine which learning activity t deliver. The LMS may identify the next learning activity in the sequence defined in the cntent structure, identify a user selected learning activity r determine which learning activity t deliver based n learner perfrmance in previusly experienced cntent bjects in an adaptive fashin. A learning activity identified fr delivery will always have an assciated cntent bject. It is the respnsibility f the LMS (r launch cmpnent/service theref) t launch the cntent bject assciated with the identified learning activity. Upn determining the apprpriate cntent bject t launch, the LMS uses the Universal Resurce Lcatr (URL) defined by the cntent bject s launch lcatin, defined in the cntent package (refer t Cde Illustratin 2-1), t navigate t, r replace the currently displayed cntent bject with the cntent bject referenced by the launch lcatin. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-2-7

26 <manifest> <rganizatins> <rganizatin> <item> <item identifierref="res_1"> </item> <item> </item> <item> </item> </item> </rganizatin> </rganizatins> <resurces> <resurce identifier="res_1" type="webcntent" adlcp:scrmtype="sc" href="lessn1/mdule1/sc1.htm"> </resurce> </resurces> </manifest> Cde Illustratin 2-1: Href used fr Launching It is the respnsibility f the LMS t determine the apprpriate fully qualified URL. The SCORM CAM defines the requirements n hw t build the fully qualified URL. The URL is built based n the fllwing pieces (if they exist in a manifest): xml:base declaratins Launch Parameters (i.e., query cmpnent [6] f a URL) Href declaratins Refer t the SCORM CAM fr mre infrmatin n the prcess invlved in building the abslute URL fr the cntent bject. The LMS may implement the launch in any manner desired r may delegate the actual launch respnsibility t the client r server prtin f the LMS as needed. The actual launch must be accmplished using the Hypertext Transfer Prtcl (HTTP). Ultimately, the cntent bject identified by the launch lcatin in a cntent package is launched and delivered t the client Web brwser Asset Fr cntent bjects that represent Assets, the SCORM launch mdel nly requires that an LMS launch the Asset using the HTTP prtcl. An Asset des nt cmmunicate t the LMS via the API and Data Mdel Sharable Cntent Object (SCO) Fr cntent bjects that represent SCOs, the SCORM launch mdel requires that an LMS launch and track ne SCO at a time (per learner). In ther wrds, the LMS launches and tracks ne SCO at a time (per learner). The LMS must launch the SCO in a Web brwser windw that is a dependent windw (i.e., pp-up windw) r child frame f the LMS windw that expses the API Instance as a Dcument Object Mdel (DOM) bject [8]. The API Instance must be prvided by the LMS. RTE-2-8 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

27 It is the respnsibility f the SCO t recursively search the parent and/r pener windw hierarchy until the API Instance is fund. Once the API Instance has been fund the SCO may initiate cmmunicatin with the LMS. Sectin 3.3: SCO Respnsibilities defines the requirements f the SCO. The SCO is respnsible fr adhering t all requirements defined by the API Instance functins (refer t Sectin 3.1: Applicatin Prgramming Interface) Taking Cntent Objects Away At the cnclusin f a learner sessin, the cntent bject currently being experienced by the learner will be taken away and replaced with the next cntent bject identified fr delivery (refer t Sectin 2.1.2: Launching Cntent Objects). Typically, cntent bjects are taken away in respnse t a learner r system triggered navigatin event (refer t the SCORM SN bk fr mre details). After the current cntent bject is taken away, the LMS needs t have the mst accurate infrmatin regarding the learner s interactins with the cntent bject t make crrect sequencing evaluatins. If the cntent bject taken away is an Asset, the LMS will make assumptins regarding the learner s interactins. If the cntent bject taken away is a SCO, the SCO may have cmmunicated mre finely grained infrmatin regarding the learner s interactins during the just ended learner sessin. It is the LMSs respnsibility t accunt fr infrmatin cmmunicated by a SCO thrugh its run-time data mdel that may affect successive sequencing evaluatins. The run-time data mdel sectin describes the LMS respnsibilities fr mapping the data mdel elements that may affect sequencing evaluatins t the learning activity assciated with the SCO. T ensure timely use f runtime data in sequencing evaluatins, it is recmmended that LMSs accunt fr run-time data changes n each cmmit data event (refer t Sectin 3: Applicatin Prgramming Interface). In sme cases, the cntent authr des nt want t allw the user t interact with the SCO after it has finished (whatever "finish" means in the cntext f the SCO). In such a case, the fllwing behavirs are allwed, depending n the type f windw in which the SCO was launched (refer t Sectin 3.2: LMS Respnsibilities): 1. If the windw in which the SCO was launched is a tp-level windw (i.e., the windw has n parent windw, but it has an pener) then the SCO may attempt t clse the windw after calling Terminate( ). There is n requirement that the SCO behave this way. It is recmmended that an LMS mnitr the status f the dependent pp-up windw in which it launched the SCO t detect when such an event happens. This will allw an LMS t present the apprpriate implementatin-defined user interface t the learner. 2. If the windw is nt a tp-level windw (i.e., the windw has a parent windw), the SCO may nt act n the parent windw r any windw in the chain f parents. Fr example, a SCO is nt allwed t attempt t clse the tp windw, unless it is its wn windw. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-2-9

28 In such a case, the recmmended behavir is fr the SCO t display neutral, passive cntent while waiting t be taken away by the LMS. RTE-2-10 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

29 SECTION 3 Applicatin Prgramming Interface (API) Frm IEEE Std IEEE Standard fr Learning Technlgy Data Mdel fr Cntent t Learning Management System Cmmunicatin, Cpyright 2004 IEEE; IEEE Std IEEE Standard fr Learning Technlgy ECMAScript Applicatin Prgramming Interface fr Cntent t Runtime Services Cmmunicatin, Cpyright 2003 IEEE; IEEE Std IEEE Standard fr Learning Object Metadata, Cpyright 2002 IEEE; and IEEE Std IEEE Standard fr Learning Technlgy Extensible Markup Language (XML) Schema Definitin Language Binding fr Learning Object Metadata, Cpyright 2005 IEEE. All rights reserved. Frm IMS Cntent Packaging v1.1.4 Cpyright 2004, by IMS Glbal Learning Cnsrtium Inc. and IMS Simple Sequencing v1.0 Cpyright 2003, by IMS Glbal Learning Cnsrtium Inc. All rights reserved. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-3-1

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31 3.1. Applicatin Prgramming Interface (API) API Overview Early versins f SCORM, up t and including SCORM Versin 1.2, were based n the run-time envirnment functinality defined in the AICC s CMI001 Guidelines fr Interperability [7]. Since then, the Aviatin Industry CBT Cmmittee (AICC) has submitted their wrk t the IEEE Learning Technlgy Standards Cmmittee (LTSC) with the emphasis t standardize varius pieces f the Cmputer Managed Instructin (CMI) Guidelines fr Interperability. SCORM describes the IEEE Standard fr Learning Technlgy - ECMAScript Applicatin Prgramming Interface fr Cntent t Runtime Services Cmmunicatin [2] as used in SCORM. The standard describes the API fr cntent t run-time service (RTS) cmmunicatin. An RTS is defined as the sftware that cntrls the executin and delivery f learning cntent and that may prvide services such as resurce allcatin, scheduling, input-utput cntrl and data management [2]. Frm a SCORM perspective, the term RTS and LMS are terms that culd be used interchangeably. The API enables the cmmunicatin f data between cntent and an RTS typically prvided by an LMS via a cmmn set f API services using the ECMAScript [9] (mre cmmnly knwn as JavaScript) language. In this sectin, the term cntent used by the IEEE standard relates t a SCO (because in SCORM, SCOs are the cntent bjects that cmmunicate t an LMS using the API). The use f a cmmn API fulfills many f SCORM s high-level requirements fr interperability and reuse. It prvides a standardized way fr SCOs t cmmunicate with LMSs, yet it shields the particular cmmunicatin implementatin frm the SCO develper. Hw the LMS-prvided API Instance cmmunicates with the server-side cmpnent f the LMS is utside the scpe f SCORM. This back-channel cmmunicatin can be implemented anyway the LMS vendr likes. There are several terms that are used thrughut SCORM: API, API Implementatin and API Instance. Figure 3.1.1a describes the terms and their relatinships t each ther. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-3-3

32 Figure 3.1.1a: Illustratin f API, API Instance and API Implementatin In its simplest terms, the API is merely a set f defined functins that the SCO can rely n being available. An API Implementatin is a piece f functinal sftware that implements and expses the functins f the API. Hw an API Implementatin functins shuld nt matter t a SCO develper, as lng as the API Implementatin uses the same public interface and adheres t the semantics f the interface. The LMS need nly prvide an API Implementatin that implements the functinality f the API and expses its public interface t the client SCO. An API Instance is an individual executin cntext and state f an API Implementatin [2]. The API Instance represents the piece f executing sftware that the SCO interacts with during the SCOs peratin. A key aspect f the API is t prvide a cmmunicatin mechanism that allws the SCO t cmmunicate with the LMS. It is assumed that nce the SCO is launched it can then stre and retrieve infrmatin with an LMS. All cmmunicatin between the LMS and the SCO is initiated by the SCO. There is currently n supprted mechanism fr LMSs t initiate calls t functins implemented by a SCO. The methds expsed by the API Implementatin are divided int three categries. Table 3.1.1b defines these categries. RTE-3-4 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

33 Methd Sessin Methds Data-transfer Methds Supprt Methds Table: 3.1.1b: Categries f API Methds Descriptin Sessin methds are used t mark the beginning and end f a cmmunicatin sessin between a SCO and an LMS thrugh the API Instance. Data-transfer methds are used t exchange data mdel values between a SCO and an LMS thrugh the API Instance. Supprt methds are used fr auxiliary cmmunicatins (e.g., errr handling) between a SCO and an LMS thrugh the API Instance API Methds and Syntax The use f a cmmn API fulfills many f SCORM s high-level requirements fr interperability and reuse. It prvides a standardized way fr SCOs t cmmunicate with LMSs, yet it shields the particular cmmunicatin implementatin frm the SCO develper. This is true if a SCO can find the API Instance in a cnsistent manner. Otherwise, cntent develpers must adapt their cntent t wrk n different LMS vendr s systems. This is ne f the primary reasns why there are restrictins n where, in the Dcument Object Mdel (DOM) hierarchy, the LMS prvides the API Instance and why there is a cmmn name f the API Instance t search. There are sme general requirements dealing with the API that shall be adhered t: All functin names are case sensitive and shall be expressed exactly as shwn. All functin parameters r arguments are case sensitive. Each call t an API functin, ther than the Supprt Methds, sets the errr cde. All parameters and return values are passed as characterstrings and shall be cmpatible with the data types and frmats described by the data mdels that use the API fr cmmunicatin. All values that are type as integers, real numbers and times are t be encded as they wuld be by the ECMAScript-t-string cast cnversin. Several examples thrughut SCORM include return data with qutes ( ). The qutes are nt intended t be part f the characterstring returned. The qutes are used t delineate the value as a characterstring. A key aspect f the API is that it allws the SCO t cmmunicate with the LMS. It is assumed that nce the SCO is launched, it exchanges (i.e., get and set ) infrmatin with an LMS. All cmmunicatin between the API Instance and the SCO is initiated by the SCO. In ther wrds, the cmmunicatin is initiated in ne directin, frm the SCO t the LMS. The SCO always invkes functins n the LMS s API Instance. The LMS des nt invke any functins defined by the SCO. This shuld nt be cnfused with the ntin f the API Instance returning a value. That is dne purely in respnse t the call initiated by the SCO. There are currently n supprted mechanisms fr LMSs t initiate calls t functins implemented by a SCO. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-3-5

34 All f the API functins are described in detail in the fllwing sectins. Sme functins refer t a data mdel. The data mdel is described in detail in Sectin 4: SCORM Run- Time Envirnment Data Mdel. Errr handling and errr cdes are described in detail in Sectin 3.1.7: API Implementatin Errr Cdes Sessin Methds A SCO uses sessin methds t initiate and terminate data cmmunicatin between itself and an API Instance Initialize Methd Syntax: return_value = Initialize(parameter) Descriptin: The functin is used t initiate the cmmunicatin sessin. It allws the LMS t handle LMS specific initializatin issues. Parameter: ( ) empty characterstring. An empty characterstring shall be passed as a parameter. Return Value: The functin can return ne f tw values. The return value shall be represented as a characterstring. The qutes ( ) are nt part f the characterstring returned, they are used purely t delineate the values returned. true The characterstring true shall be returned if cmmunicatin sessin initializatin, as determined by the LMS, was successful. false The characterstring false shall be returned if cmmunicatin sessin initializatin, as determined by the LMS, was unsuccessful. The API Instance shall set the errr cde t a value specific t the errr encuntered. The SCO may call GetLastErrr() t determine the type f errr. Mre detailed infrmatin pertaining t the errr may be prvided by the LMS thrugh the GetDiagnstic() functin Terminate Methd Syntax: return_value = Terminate(parameter) Descriptin: The functin is used t terminate the cmmunicatin sessin. It is used by the SCO when the SCO has determined that it n lnger needs t cmmunicate with the LMS. The Terminate() functin als shall cause the persistence f any data (i.e., an implicit Cmmit( ) call) set by the SCO since the last successful call t Initialize( ) r Cmmit( ), whichever ccurred mst recently. This guarantees t the SCO that all data set by the SCO has been persisted by the LMS. Once the cmmunicatin sessin has been successfully terminated, the SCO is nly permitted t call the Supprt Methds. RTE-3-6 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0

35 Parameter: ( ) empty characterstring. An empty characterstring shall be passed as a parameter. Return Value: The methd can return ne f tw values. The return value shall be represented as a characterstring. The qutes ( ) are nt part f the characterstring returned, they are used purely t delineate the values returned. true The characterstring true shall be returned if terminatin f the cmmunicatin sessin, as determined by the LMS, was successful. false The characterstring false shall be returned if terminatin f the cmmunicatin sessin, as determined by the LMS, was unsuccessful. The API Instance shall set the errr cde t a value specific t the errr encuntered. The SCO may call GetLastErrr() t determine the type f errr. Mre detailed infrmatin pertaining t the errr may be prvided by the LMS thrugh the GetDiagnstic() functin Data-Transfer Methds A SCO uses data-transfer methds t direct the strage and retrieval f data t be used within the current cmmunicatin sessin. The SCO uses these methds t transfer runtime data t and frm the LMS. Fr example, the LMS can use this data t help determine cmpletin/mastery f activities and make sequencing and navigatin decisins GetValue Methd Syntax: return_value = GetValue(parameter) Descriptin: The functin requests infrmatin frm an LMS. It permits the SCO t request infrmatin frm the LMS t determine amng ther things: Values fr data mdel elements supprted by the LMS. Versin f the data mdel supprted by the LMS. Whether r nt specific data mdel elements are supprted. Parameter: The parameter represents the cmplete identificatin f a data mdel element. Return Value: The methd can return ne f tw values. The return value shall be represented as a characterstring. A characterstring cntaining the value assciated with the parameter If an errr ccurs, then the API Instance shall set an errr cde t a value specific t the errr and return an empty characterstring ( ). The SCO may call GetLastErrr() t determine the type f errr. Mre detailed infrmatin pertaining t the errr may be prvided by the LMS thrugh the GetDiagnstic() functin. SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0 RTE-3-7

36 The SCO shuld nt rely n an empty characterstring returned frm this functin as being a valid value. The SCO shuld check t see if the errr cde indicates that n errr was encuntered. If this is the case, then the empty characterstring is a valid value returned frm the LMS. If an errr cnditin was encuntered during the prcessing f the request, then this wuld be indicated by an apprpriate errr cde (refer t Sectin 3.1.7: API Implementatin Errr Cdes) SetValue Methd Syntax: return_value = SetValue(parameter_1, parameter_2) Descriptin: The methd is used t request the transfer t the LMS f the value f parameter_2 fr the data element specified as parameter_1. This methd allws the SCO t send infrmatin t the LMS fr strage. The API Instance may be designed t immediately persist data that was set (t the server-side cmpnent) r stre data in a lcal (client-side) cache. Parameter: parameter_1 The cmplete identificatin f a data mdel element t be set. parameter_2 The value t which the cntents f parameter_1 is t be set. The value f parameter_2 shall be a characterstring that shall be cnvertible t the data type defined fr the data mdel element identified in parameter_1. Return Value: The methd can return ne f tw values. The return value shall be represented as a characterstring. The qutes ( ) are nt part f the characterstring returned, they are used purely t delineate the values returned. true The characterstring true shall be returned if the LMS accepts the cntent f parameter_2 t set the value f parameter_1. false The characterstring false shall be returned if the LMS encunters an errr in setting the cntents f parameter_1 with the value f parameter_2. The SCO may call GetLastErrr() t determine the type f errr. Mre detailed infrmatin pertaining t the errr may be prvided by the LMS thrugh the GetDiagnstic() functin Cmmit Methd Syntax: return_value = Cmmit(parameter) Descriptin: The methd requests frwarding t the persistent data stre any data frm the SCO that may have been cached by the API Instance since the last call t Initialize( ) r Cmmit( ), whichever ccurred mst recently. The LMS wuld then set the errr cde t 0 (N Errr encuntered) and return true. If the API Instance des nt cache values, Cmmit( ) shall return true and set the errr cde t 0 (N Errr encuntered) and d n ther prcessing. RTE-3-8 SCORM rd Editin Run-Time Envirnment (RTE) Versin 1.0