System concepts and architecture

Question 1

Define a system

Answer 1

*“A system is a collection of components
linked together and organized in such a
way as to be recognizable as a single
unit.”
*Linked components of a system also
define a boundary for the system
*The environment is anything outside of
the system

Question 2

System decomposition

Answer 2

Components
*May be irreducible or
*May be subsystems

Decomposition
*The division of a system into its
components and linkages
*Hierarchical

Question 3

Define system architecture

Answer 3

“The fundamental properties, and the
patterns of relationships, connections,
constraints, and linkages among the
components and between the system and
its environment are known collectively as
the architecture of the system”

Question 4

Describe IT System Architectures

Answer 4

Distributed processing systems
*Client-Server Computing
*Two-tier architecture
*Three-tier architecture
*N-tier architecture
*Web-Based Computing
*Cloud Computing
*Peer-to-Peer Computing

Question 5

Advantages of Client-Server
Architecture

Answer 5

Centralization of services permits
*easier administration of services by IT
professionals
*easier availability and location by users
*consistency of resources, such as files
and data, can be managed and assured
*more efficient and cost-effective
hardware procurement through
purchasing a small number of very
powerful computers

Question 6

What is Multi-tier Architectures?

Answer 6

Two-tier architecture
*Two computers are involved in a service
*Example: Web browser and Web server
model used in intranets and on the
Internet

Three-tier architecture
*Three computers are involved in a service
*Example: client computer, Web server,
database server
*N-tier architecture