chapter 9

Question 1

model

Answer 1

a pictorial representation of reality

Question 2

logical model

Answer 2

a non technical pictorial representation that depicts what a system is or does

reduce the risk of missing business requirements

Question 3

physical model

Answer 3

a technical pictorial representation that depicts what a system is or does and how the system is implemented

Question 4

process modeling

Answer 4

a technique used to organize and document a systems processes

Question 5

data flow diagram (DFD)

Answer 5

a process model used to depict the flow of data through a system and the work or processing performed by the system

Question 6

external agents

Answer 6

an outside person, unit, system, or organization that interacts with a system.

also called an external entity

Question 7

data stores

Answer 7

stored data intended for later use

Question 8

process

Answer 8

worked performed by a system in response to incoming data flows

Question 9

process concepts

Answer 9

1. data stays at rest unless moved by a process

2. processes cannot consume or create data by themselves

Question 10

data flow

Answer 10

data that is input to or output from a process

Question 11

context level diagram

Answer 11

top level view of info system

shows system boundaries. includes one process, external agents, and main data flows

Question 12

level 0 diagram

Answer 12

shows the systems major processes, data flows, and data stores at a high level of abstraction

Question 13

decomposition

Answer 13

the act of breaking a system into sub-components

Question 14

decomposition diagram

Answer 14

tool used to depict the decomposition of a system. also called a hierarchy chart