attachment:SCORM-RTE.pdf

SCORM Run-Time Environment Overview

• sharable content objects (SCOs) communicate during run-time
• assets, do not communicate during run-time

RTE Book describes communication mechanism between content objects and LMSs, as well as a common data model for tracking learner's experience with content objects.

3 aspects of the Run-Time Environment are Launch, Application Programming Interface (API) and Data Modle.

Communication Session - an active connection between a content object (i.e., SCO) and an application programming interface.

SCORM Content Model is made up of three components:

• Assets
• SCOs
• Content Aggregations

SCORM Content Aggregation Model describes the characteristics of launchable content objects; SCOs and Assets are defined content model components that can be launched. LMS is responsible for managing sequencing. Sequencing may be sequential, non-sequential, user-directed, or adaptive.

LMS must launch SCO in a browser window that is a child window of the LMS window that exposes the API instance as a DOM object. It is the responsibility of the SCO to recursively search the parent and/or opener window heirarchy until the API Instance is found. Once the API Instance has been found the SCO may initiate communication with the LMS. The SCO must adhere to the API Instance functions. (2.1.2)

The API enables the communication of data between content and an RTS typically provided by an LMS via a common set of API services using the ECMASCript, more commonly known as javascript, language. In it's simplest terms, the API is merely a set of defined functions that the SCO can rely on being available.

Methods exposed by the API Implementation are divided into three categories:

• Session Methods - used to mark the beginning and end of communication
• Data-transfer Methods - used to exchange data between a SCO and an LMS through the API Instance
• Support Methods - used for auxiliary communcations (e.g., error handling) between a SCO and an LMS through the API Instance.

3.1.2 All communication between the API Instance and the SCO is initiated by the SCO. Communication is initiated in one direction, from the SCO to the LMS.

3.1.4 Data Transfer Methods

used by the SCO to direct the storage and retrieval of data that is to be used within the current communication session. SCO uses these methods to transfer run-time data to and from the LMS. LMS can use this data to help determine completion/mastery of activities and make sequencing and navigation decisions.

3.1.5 Support Methods

Allow SCO to determine error handling and diagnostic information.

3.2.1 API Instance

LMS API Instance must be accessible via the DOM as an object named "API_1484_11". THe LMS is responsible for launching SCOs in a particular DOM hierarchy. The LMS shall launch the SCO in a browser window that is a child window or a child frame of the LMS window that contains the API Instance.

Once a SCO finds an API Instance, the SCO is required to, at a minimum, issue Initialize("") and Terminate("")

see: p.59 for code to accomplish finding the API.

4.1 Data Model Overview