Information Systems: Activities and Processes

• Systems documentation is an interrelated set of system narratives, tables, and diagrams that describe how an information system (IS) works
• Accountants need to read, analyze, and prepare systems diagrams to understand, assess, and document IS processes

Diagram Elements - Activities

• An activity is an action or task performed for a specific purpose
• There are 2 types of activities: information processing and non-information processing activities
• Information processing involves capturing, processing, storing, or distributing information
• Non-information processing fulfills an operational aspect of the business
• The simple sending or receiving of data between entities is not considered an information processing task

Processes

• The data processing cycle, also known as the information processing cycle, includes data capture, processing, maintenance, and distribution
• A process is a series of activities to fulfill a specific purpose
• A subprocess, or logical subprocess, is a group of logically related activities within a larger process used for diagramming
• Operations processes are non-information processing activities to fulfill the business's central functions
• Information processes are information processing activities that convert data into information to track and support operations processes

Entities

• An entity is an autonomously functioning person, place, or thing associated with an IS process
• An internal entity performs an information processing activity within the scope of analysis
• An external entity doesn't perform information processing but sends or receives data
• Whether an entity is internal or external depends on whether it performs an information processing activity within the defined scope
• A source initiates a process by "sending" data and can be external or internal
• A sink concludes a process by "receiving" data and can be external or internal

Flows

• A data flow is a transfer of data between entities or subprocesses in a DFD and can be manual or electronic
• A logical flow indicates the direction of data or task flows within a system flowchart
• In system flowcharts, activities typically flow from top to bottom and left to right
• Unidirectional flow goes in one direction, indicated by a single-headed arrow
• Multidirectional flow goes both directions, indicated by two single-headed arrows or a double-headed arrow

Documents, Files and Reports

• Documents are manual or electronic forms supporting data processing
• Files are logically related sets of records; databases are centrally managed sets
• Reports summarize information in a standardized or non-standardized form

System Documentation

• Complete systems documentation includes a system narrative, table of entities and activities, data flow diagrams, and a system process flowchart

Narratives & Tables

• A system narrative is a chronological description of entities, activities, data flows, documents, files, and reports, usually written in prose with paragraph and line numbers
• A table of entities and activities organizes the entities and activities from the narrative in chronological order, including the entities, activities, and paragraph/line references

System Diagrams

• A system diagram is a graphical representation of system elements and processes

Data Flow Diagram Types

• The context DFD shows the process of interest and external data flows; the physical DFD shows who or what performs activities
• The logical DFD shows what logical subprocesses are performed.
• All DFD types have different views of the system

Context Data Flow Diagram

• The context DFD is a top-level diagram of the process and its external environment, it shows the process as a whole, external entities.
• Use noun labels for the process, entities, and data flows; doesn't show internal details or use verb labels

Physical Data Flow Diagram

• The physical DFD Shows who or what performs processes, portrays internal entities and data flows between them.
• Like the context DFD, the physical DFD uses noun labels to describe the external entities, internal entities

Logical Data Flow Diagram

• The logical DFD shows what logical subprocesses are performed, it focuses on internal subprocesses and data flows between them
• verbs (actions) to describe subprocesses and nouns to describe entities, file stores, and data flows

System Flowchart

• A system flowchart is a detailed diagram showing who/what performs activities and how.
• Physical and logical DFDs have different views, and the flowchart has all aspects of the process
• System inputs, activities, outputs, flows, data stores and connectors are represented by specific symbols

Diagram Symbols

• Data flow diagram symbols are simple shapes showing entities, subprocesses, file stores, and data flows
• Flowchart symbols are classified as input, processing, output, data store, and connector symbols, each with a specific meaning

Additional Diagram Concepts

• Annotation is a comment linked to a symbol

Balance

• DFD balance means consistency of external entities and external data flows across all DFDs
• Exploding is breaking down a top-level entity or subprocess for more detail
• DFD levels refer to the level of detail: level 0 is a top-level view, and level 1 breaks down components

Routines

• Exception/error routines are atypical activities, and error routines are performed when errors occur

Preparing System Documentation - General Notes

• Narratives and tables of entities and activities must be properly formatted and labeled
• Diagrams must use the correct, standardized symbols

Preparing Narratives and Tables

• Identify relevant entities, activities, and data flows
• Define the scope of analysis with a starting and stopping point
• Narratives should describe system elements in detail, focusing on elements within the defined scope; include descriptions of entities/activities just outside the defined scope to afford context
• System narratives must be written in prose form and describe the "process story" with a chronological sequence of actions/tasks
• Subject sentences must define the company and the process being described
• Paragraphs should indicate breaks in processing activities, writing should be clear and succinct, and the narrative should be carefully proofread
• The last sentence should state where outputs are sent

Formatting

• Tables should be formatted in four columns: Entities, P, L (paragraph and line), Activities, and Subprocesses
• Entities column indicates entities performing activities and whether they are internal (I) or external (E)
• P, L indicates the paragraph and line number where each activity starts in the narrative
• Content of Tables
• The table should include paragraphs/line references and numbered activities in chronological order

Steps for tables

• Read narrative and mark each activity (both information and non-information processing)
• List the entities, maintaining consistent labels
• Construct a table and list activities and entities in order
• Activities are listed in order and the paragraph line indicated where the activity is described ###Logical Sub-Processes
• Note the logical subprocessess by annotating them
• A logical subprocess is a specific piece of logically organized activities
• List in order that each process is done and create annotationg based on order
• This process aims to simply tasks preformed by the user
• Steps to use logical subprocessess
• Mark activities that “go together”
• Verbally say the activity with 2 or 3 words eg. "Prepare cash depostis"
• Link process label on top with a table with entities

Steps to make your table more efficient remember the following points:

• List only tasks descirbed in narrative
• You must revise the narrative system If information is missing

Data Flow Diagrams

• Context diagrams need external entities and external data flows
• Always use label when refering to the nature of the external entity
• Position your shapes accordingly for effective representation of the data
• Data flow lines (arrows) must not touch and always have direction / clearly point it out

Physical DFD

• Use your table to determine internal processes
• Place the entities chronologicaly in the center of your drawing
• Create doube lines to symbols
• Make sure that no lines or processes are interupted or cut of
• Computer files can only be accessed through entities via Computer sysems

Logical DFD

• Use your table to check content and order for effective flow of data
• Use correct label with correct type

Sytem FLowcharts

• Should show internal processes and their data flows
• Divide drawing in columns corresponding to internal entities
• External entities need to show the “sends” and/or “receives”
• Draw activities, top to bottom with a chronological order
• Flow lines should cut accross but in other collumns to stop interuption
• The most important rules to follow in this class for system flowcharts
• Inuts flow into chart and entities
• Processing occurs and it may take an annotation
• After a file has been created the file must be saved to a destination
• If your entity terminates the system has worked and then they will have to select a new way

Explanation of system documentation, activities, and processes. Activities are explained as actions or tasks performed for a specific purpose, including information processing and non-information processing. The data processing cycle, also known as the information processing cycle, includes data capture, processing, maintenance, and distribution.