Software Process Framework 1 Umbrella Activity Software project

Software Process Framework 1

Umbrella Activity • • Software project management Formal technical reviews Software quality assurance Software configuration management Work product preparation and production Reusability management Measurement Risk management

Example of Task Set for Req. Gathering 1. Make a list of stakeholders for the project. 2. Invite all stakeholders to an informal meeting. 3. Ask each stakeholder to make a list of features & functions required. 4. Discuss requirements and build a final list. 5. Prioritize requirements. 6. Note areas of uncertainty.

Software Process Definition: Software process is defined as framework for the activities , actions & task that are required to build high quality software

Process Flow

Prescriptive Process Model • Definition: Prescribed set of process elements and a predictable process work flow is called as Prescriptive process model.

1. Waterfall Process Model

Disadvantages of Waterfall Model 1. It is difficult to customer to state all requirements explicitly. 2. Working version of program is available late in Project time span 3. Linear model leads ‘Blocking state’ due to dependent task.

V Model

V- Model • Variation in representation of Waterfall model is called V model. • V Model Provides a way of visualizing how verification and validation actions are applied to engineering work.

3. Incremental Model (RAD)

Incremental Model • Incremental model combines elements of linear and parallel process flow • First increment is “Core Product” • Useful when resources are not available for complete implementation • Eg. Word processing software • Basic Product is delivered with partial functionality without delay.

1. Prototyping

Prototyping Continued… • Customer defines general set of objectives for software but does not identify detailed system requirement • Prototyping assist you & other stakeholder to better understand system when requirements are Fuzzy • Serve as mechanism of identifying software requirement

2. Spiral Model

Spiral Model • Risk driven process model • Features – Cyclic in nature; incrementally growing system’s degree of implementation and decrease degree of risk. – Anchor point milestones are set for ensuring stakeholder commitment of system solution. – Increasingly more complete version of engineered system is produced. – Remains operative until software is retired.

Concurrent Process Model

Concurrent Process Model • Also called Concurrent engineering. • All software engg. Activities exist concurrently but resides in different state.

Advance Process Models 1. Unified Process

2. Extreme Programming XP Process

XP Values 1. Communication: avoid voluminous documentation. 2. Simplicity XP restricts developers to design only for immediate needs rather than future needs 3. Feedback s/w, customer, other team members 4. Courage Demanding rework of the design and code. 5. Respect

XP Stories developed in 3 ways 1. All stories will be implemented immediately (within a few weeks), 2. Stories with highest value will be moved up in the schedule and implemented first, or 3. High Risk stories will be moved up

• User stories implemented are used as basis for acceptance test • Issues Raised by XP 1. Requirements volatility 2. Conflicting customer needs 3. Requirements are expressed informally

Class Responsibility Collaborator Class Name Super class: Subclass: Responsibilities Collaborator

CRC Example Librarian Responsibilities Collaborator Issue Book Return Book Search for Book Knows all Book Borrower Search for Borrower Knows all Borrower