Paper 1 Mod 2

Question 1

What is a software development methodology?

Answer 1

A structured and controlled framework used to plan, manage, and guide the process of creating an information system.

Question 2

What are the key characteristics of software development methodologies?

Answer 2

They have the same final outcome and similar stages, but differ in approach and teamwork dynamics.

Question 3

List five software development methodologies you need to be aware of.

Answer 3

• Waterfall
• Agile
• Extreme Programming
• Spiral
• Rapid Application Development

Question 4

Describe White Box Testing.

Answer 4

Uses detailed insider knowledge of the target system to improve tests and utilizes the source code.

Question 5

What are the benefits of White Box Testing?

Answer 5

• Leads to deep and more detailed testing
• Requires less testing time
• Tests quality of code and app design

Question 6

Describe Black Box Testing.

Answer 6

Requires no previous information and takes the approach of an uninformed attacker without access to the source code.

Question 7

What are the benefits and disadvantages of Black Box Testing?

Answer 7

• Benefits: Simulates a realistic scenario
• Disadvantages: Tests take longer and some areas may remain untested

Question 8

What is the Waterfall methodology?

Answer 8

A traditional methodology involving a linear plan where each task feeds into the next.

Question 9

What is a major drawback of the Waterfall methodology?

Answer 9

It is rigid and does not allow going back to previous stages once completed.

Question 10

What are the four phases of the Spiral Methodology?

Answer 10

• Planning
• Risk Analysis
• Engineering
• Evaluation

Question 11

What is a key focus of the Spiral Methodology?

Answer 11

Risk management and adaptability to changing requirements.

Question 12

What is the Agile methodology?

Answer 12

Breaks projects into dynamic phases called sprints, using an iterative approach.

Question 13

What is the role of teamwork in Agile methodology?

Answer 13

Teamwork and collaboration are central, with constant communication and customer involvement.

Question 14

Describe Extreme Programming.

Answer 14

A form of agile development emphasizing frequent releases and short development cycles.

Question 15

What is Test Driven Development in Extreme Programming?

Answer 15

Tests are written before the code to ensure requirements are met.

Question 16

What is Rapid Application Development (RAD)?

Answer 16

A methodology that focuses on fast project completion and prototype creation with minimal planning overhead.

Question 17

What are some key features of Rapid Application Development?

Answer 17

• Swift creation of prototypes
• Minimal planning overhead
• Workshops with little documentation
• Reuse of software components

Question 18

Fill in the blank: Agile methodology adapts to _______.

Answer 18

[changes in requirements]

Question 19

True or False: The Waterfall methodology is flexible and allows for changes at any stage.

Answer 19

False

Question 20

What does the Spiral Methodology allow for after each evaluation phase?

Answer 20

Begins a new planning phase informed by evaluation results.

Question 21

What is a key benefit of using prototypes in RAD?

Answer 21

Constant feedback until the prototype becomes the final product.

Question 22

What is paging?

Answer 22

Paging is when memory is split up into equal-sized sections known as pages, with programs being made up of a certain number of equally-sized pages.

Question 23

What is segmentation?

Answer 23

Segmentation is the splitting up of memory into logical sized divisions, known as segments, which vary in size. These are representative of the structure and logical flow of the program, with segments being allocated to blocks of code such as conditional statements or loops.

Question 24

What is virtual memory?

Answer 24

It is when a section of secondary storage is used to act as RAM when the space in main memory is insufficient to store programs being used. Sections of programs that are not currently in use are temporarily moved into virtual memory through paging. The new programs are then loaded to memory.

Question 25

What is a disadvantage of virtual memory?

Answer 25

Disk thrashing :- where the computer freezes and it spends more time moving items from RAM to secondary storage and the other way around than decoding and executing instructions.

Question 26

What is an interrupt?

Answer 26

Interrupts are signals generated by software or hardware to indecate to the processor that a process needs attention. Different types of interrupts have different priorities and how urgent they are must taken into accont by the operating system when allocating processor time.

Question 28

How does the interrupt service routine work?

Answer 28

The processor checks the contents of the interrupt register at the **end** of each fetch-decode-execute cycle. If an interrupt exists that is of a higher priority to the process being executed, the current contents of the special purpose registers in the CPU are temporarily transferred into a stack. The processor then responds to the interrupt by loading the appropriate interrupt service routine to RAM. A flag is set to signal the ISR has begun. Once the interrupt has been services, the flag is reset.

Question 29

What is scheduling?

Answer 29

It is a method where the OS has to ensure all sections of programs being run recieve a fair amount of processing time.

Question 30

What are pre-emtive scheduling algorithms?

Answer 30

Jobs are actively made to start and stop by the operating system. Examples :- Multilevel feedback queues, shortest remaining time, Round robin.

Question 31

What are non pre-emptive scheduling algorithms?

Answer 31

Once a job is started, it is left alone until it is completed. Examples :- First come First serve, Shortest Job first.

Question 32

What is the round robin scheduling algorithm?

Answer 32

Each job gets an equal, fixed time slice (quantum) to execute before moving to the next job in the queue. Ensures all jobs are processed equally, preventing starvation. Longer jobs take more cycles to complete because their execution is split into small, interrupted segments. Jobs are treated equally, regardless of urgency or importance.

Question 33

What is the First come first served scheduling algorithm?

Answer 33

Jobs are processed in chronological order by which they entered the queue. FCFS doesn't support priorites.

Question 34

What is the Multilevel feedback queues scheduling algorithm?

Answer 34

This makes use of multiple queues, each which is ordered based on a different priority. This can be difficult to implement due to deciding which job to prioritise based one a combination of priorities.

Question 35

What is the Shortest job first scheduling algorithm?

Answer 35

Queue Order: Jobs are sorted by completion time, with the shortest jobs processed first. Goal: Minimizes average waiting time for jobs, ideal for batch systems. The processor must know/estimate each job’s duration (not always possible). Starvation of longer jobs if short jobs keep entering the queue.

Question 36

What is the Shortest remaining time scheduling algorithm?

Answer 36

Shorter timer left jobs have priority Preemptive: The OS can interrupt a running job if a shorter job arrives.

Question 37

What are linkers?

Answer 37

This is a piece of software that is responsible for linking external modules and libraries included within the code.

Question 38

What are static linkers?

Answer 38

Modules and libraries are added directly into the main file. This increases the size of the file. Any updates to modules and libraries externally will not affect the program.

Question 39

What are dynamic libraries?

Answer 39

Addresses of modules and libraries are included in the file where they are referenced. When the program is run, the loader retrieves the program at the specified address so it can be executed.

Question 40

What is a loader?

Answer 40

Loaders are programs provided by the operating system. When a file is executed, the loader retrieves the library or subroutine from the given memory location.

Question 41

What is alpha testing?

Answer 41

Alpha testing is carries out in-hour by the software development teams within the company.

Question 42

What is beta testing?

Answer 42

Beta testing is carried out by end-users after alpha testing has been completed. Feedback from users is used to inform the next stage of development.

Question 44

What is the waterfall model?

Answer 44

Description: Sequential and linear software development approach. Process: Divided into distinct phases (requirements, design, implementation, testing, maintenance). Advantages: Clear structure, easy to understand and manage, well-suited for projects with stable requirements. Disadvantages: Limited flexibility for changes, long feedback loop, high risk of late-stage changes.

Question 45

What is agile methodology?

Answer 45

Description: Iterative and incremental software development approach. Process: Emphasizes collaboration, adaptability, and customer feedback throughout the development process. Advantages: Flexibility to adapt to changing requirements, customer involvement, early and continuous delivery of working software. Disadvantages: Requires active customer involvement, may be challenging for large or distributed teams.

Question 46

What is Extreme Programming?

Answer 46

Description: Agile methodology emphasizing high-quality software development practices. Process: Iterative development with a focus on customer satisfaction, continuous testing, and frequent releases. Advantages: Emphasis on teamwork, customer involvement, and software quality. Disadvantages: Requires skilled developers, may be challenging for inexperienced teams.

Question 47

What is spiral methadology?

Answer 47

Description: Combines elements of both waterfall and iterative development models. Process: Iterative approach with risk management at its core, involving multiple cycles of planning, risk analysis, development, and evaluation. Advantages: Risk-focused approach, flexibility in incorporating changes, good for large and complex projects. Disadvantages: High cost and time investment, complex to manage.

Question 48

What is rapid application development?

Answer 48

Description: Emphasizes rapid prototyping and quick development cycles. Process: Iterative development with a focus on prototyping, user feedback, and quick iterations. Advantages: Faster development cycles, customer involvement, early feedback. Disadvantages: May sacrifice long-term maintainability for speed, requires highly skilled team members.

Question 49

What is a programming paradigm?

Answer 49

They are different approaches to using a programming language to solve a problem. They split into two main catagories - imperative and declarative.

Question 50

What is a imperative paradigms?

Answer 50

They use code that clearly specifies the actions to be performed to reach the solution.

Question 51

What is a declarative paradigm?

Answer 51

They focus on stating the desired result rather than how to get there, How the result is obtained is either hidden from the user or is heavily abstracted.