INFO 1113 v2

• What does FSM stand for? FSM (Finite-State Machines)
• What does DFD mean?

  Data Flow Diagram
• Data flow diagram (DFD)


  A picture of the movement of data between external entities and the processes and data stores within a system
• Deliverables for process modeling

  1. Context DFD

  2. DFSs of the system

  3. Thorough descriptions of each DFD component
• Data flow


  Data in motion, moving from one place in a system to another
• According to the DFD conventions, data flow is depicted by an arrow
• Data flow characteristics

  • Data that move together, composed of many individual pieces of data that flow together to common destinations
• DFD symbols consist of four symbols representing data flows, data stores, processes, and sources/sinks (or external entities)
• FSM

  Finite-State Machines
• Conceptual data modeling


  1. Developing a model for the current system

  2. Refining for the proposed system
• Primary key


  Unique characteristic that distinguishes each object from other objects of the same type
• Entity


  A person, place, object, event, or concept in the user environment about which the organization wishes to maintain data
• Entity types in an E-R model are given a singular name representing a class or set
• Attribute


  A named property or characteristic of an entity that is of interest to the organization
• Binary relationship


  A relationship between instances of two entity types
• Entity instance


  A single occurrence of an entity type, described just once in a data model
• Data flow diagram (DFD)


  A picture of the movement of data between external entities and the processes and data stores within a system
• Deliverables for process modeling

  1. Context DFD

  2. DFSs of the system

  3. Thorough descriptions of each DFD component
• Data flow


  Data in motion, moving from one place in a system to another
• According to the DFD conventions, data flow is depicted by an arrow
• Data flow characteristics


  • Data that move together, composed of many individual pieces of data that flow together to common destinations
• DFD symbols consist of four symbols representing data flows, data stores, processes, and sources/sinks (or external entities)
• FSM

  Finite-State Machines
• Conceptual data modeling


  1. Developing a model for the current system

  2. Refining for the proposed system
• Primary key


  Unique characteristic that distinguishes each object from other objects of the same type
• Entity


  A person, place, object, event, or concept in the user environment about which the organization wishes to maintain data
• Attribute


  A named property or characteristic of an entity that is of interest to the organization
• Binary relationship


  A relationship between instances of two entity types
• Entity instance


  A single occurrence of an entity type, described just once in a data model