CPSA-FL 無料問題集「ISQI ISAQB Certified Professional for Software Architecture - Foundation Level」
Concerning external interfaces, Postel's law suggests: "Be conservative in what you do, be liberal in what you accept from others." Assume that Postel's law has been consistently applied in your system. (Assign all answers.)
正解：
Explanation:
A) FalseB) FalseC) FalseD) TrueE) TrueF) False
Postel's law, also known as the robustness principle, is a guideline in software engineering that advises to "be conservative in what you do, be liberal in what you accept from others"1. This principle has implications for system design and interaction with external interfaces:
A) Response time of the system is reduced: This is false. Postel's law does not directly relate to the response time of a system1.
B) Implementation effort increases: This is false. Being liberal in what is accepted can actually simplify implementation because the system is designed to handle a wider range of inputs without failure1.
C) Usability of the system is reduced: This is false. Postel's law aims to increase robustness and interoperability, which can enhance usability by making the system more resilient and accommodating1.
D) Robustness of the system is increased: This is true. By being conservative in outputs and liberal in inputs, the system becomes more robust, handling a variety of inputs without error1.
E) The integrity of the data transferred via interfaces is increased: This is true. Accepting a wide range of inputs and adhering strictly to output specifications helps maintain data integrity across different systems1.
F) Availability of the system is reduced due to potentially bad quality of input data: This is false. Postel's law suggests that the system should be designed to handle poor quality input data gracefully, thus maintaining availability1.
Applying Postel's law helps create systems that are more tolerant of input variations and strict in their outputs, contributing to overall system robustness and reliability1.
What is the purpose of defining the system context? (Assign all answers.)
正解：
Explanation:
The purpose of defining the system context includes:
* To illustrate the system's interfaces with external systems (B) - True
* To clarify the area of responsibility of the software architect C - True
* To represent the external systems (D) - True
* To distinguish between infrastructure and application (E) - True
* To distinguish between the hardware and software of a solution (F) - True Defining the system context is a crucial step in software architecture as it helps to establish the boundaries and interactions of a system within its environment. Here's a detailed explanation of the purposes:
* To Illustrate the System's Interfaces with External Systems (B): It is essential to understand how the system interacts with other systems, which can influence requirements and design1.
* To Clarify the Area of Responsibility of the Software Architect : By defining the system context, the architect's responsibilities regarding the system's interactions and boundaries are made clear1.
* To Represent the External Systems (D): The system context helps identify and represent all external entities that interact with the system, which is important for comprehensive design and analysis1.
* To Distinguish Between Infrastructure and Application (E): Understanding the system context allows for a clear distinction between the infrastructure (the environment in which the application operates) and the application itself1.
* To Distinguish Between the Hardware and Software of a Solution (F): The system context helps to differentiate between the hardware components and the software components of a system, which is vital for system integration and deployment1.
These aspects of the system context are fundamental for ensuring that the system is designed and developed to meet its intended goals and operate effectively within its designated environment.
References:
* Smartpedia article on System Context1.
* Visual Paradigm Blog on System Context Diagrams2.
* microTOOL article on System Context3.