SCRUM method)

I saw a book Agile Project Management with scrum these days, and I found some related information on the Internet.

The SCRUM method is as follows:

By Ken
Schwaber and Jeff Sutherland
The aim is to seek to give full play to the development methods of object-oriented and component technologies, which is to improve iterative object-oriented methods, the name is from rugby (in the competition, every player should always judge the overall situation on the court.
Break, and then strive to achieve the same goal through collective action-victory ). The SCRUM method was originally used by Easel (1993) and has been used by hundreds of projects in dozens of companies.
Used for the development of complex business application products with unpredictable requirements [11]. Scrum meeting, sprint, backlog, and scrum proposed by scrum
The master, scrum team, demo, and other models have been used by plop as the organization and Process Model (organizational and process ).
Pattern) standard [12].
Scrum applies the concept of industrial process control to software development, and thinks that the software development process is more an empirical process (empirical
Process), rather than the deterministic process (defined
Process ). A Deterministic process is a descriptive and predictable process. It can be executed repeatedly and produce expected results, and can be optimized through scientific theories.
The empirical process, on the contrary, should be used as a black box (black
The input and output of the black box are constantly measured. On this basis, the Black Box is adjusted based on experience judgment so that it does not go beyond the set boundary, thus produce satisfactory output. Scrum party
The analysis, design, and implementation in traditional development are considered as a black box. The chaos in the black box should be strengthened so that the project team can work on the edge of chaos and give full play to the creativity of people. For example, the empirical process is deterministic.
Process processing (such as Waterfall Model) will make the process less adaptable.
3.2.1 development process of SCRUM Method
There are three processes:
(1) planning and architecture design (deterministic process)
Integrate the Backlog (a series of tasks that need to be completed urgently, including: unrefined product functional requirements, Bugs, defects, user-proposed improvements, competitive features and technical upgrades) A Backlog list is generated by priority, and a product delivery baseline is developed based on the table and risk assessment.
Create
Establish the system architecture (for example, to improve the existing system, only perform limited Analysis and Adjustment), and separate the Backlog items into a series of problem packages based on the principle of high cohesion and low coupling (Packets, each
Packet is a set of objects or components. based on the same principle, several development teams (SCRUM
Group), assign appropriate Backlog items or problem packages to each group. Create a development and running environment.
(2) Sprint (empirical process)
This process is composed of several iterations
Sprint)
Activities until the risk assessment considers the product to be deliverable. A Sprint is within a limited period of time (the Sprint cycle is usually 1 ~ 6 weeks, which can be adjusted at the end of the previous Sprint)
A series of development activities (including analysis, design, coding, testing, etc.), each SCRUM team is developed in parallel and must be consistent in steps (after a Sprint ends, all allocated
Backlog items with executable output ).
Each Sprint contains the following activities:
L development. Analyze the assigned Backlog, map the required changes (changes) to each packets, open packets, perform domain analysis, and design, develop, implement, test, and document the changes.
L package (Wrap ). Encapsulate packets to generate an executable version that meets the Backlog requirements.
L
Review ). All scrum teams have a meeting, submit their work and demo, and then propose and solve the problem (Issue) and the difficulty (problem ),
Add new backlog items; release, review or adjust product standard specifications; conduct risk assessment and propose appropriate countermeasures; determine the work content and end time of the next sprint.
L adjustment (adjust ). Adjust and consolidate the affected packages according to the information collected by the review.
(3) delivery and consolidation (deterministic process)
This phase is entered once the product is considered deliverable based on the risk assessment results. Activities in this phase include Assembly, system testing, and regression, preparation of training materials, and completion of final documents.
The SCRUM process assumes that the development of a product will continue unless it is deemed that it should be stopped after risk assessment. After the product is delivered, the consolidation activities are similar to the maintenance and improvement in the traditional method. The purpose is to sort out the work neglected under the pressure of the sprint, and prepare for the development of the next stage, so that it can be easily loaded.
3.2.2 scrum Process Management:
(1) scrum control means.
Scrum proposed eight controls for the control of the development process. Risk Control is the primary means.
L backlog.
L object/component.
L packets.
L change (changes ). Changes to the corresponding packet when a backlog entry is implemented.
L difficulty (problems ). Technical difficulties that must be addressed when a change is implemented.
L problem (issues ). Issues that need to be resolved before the entire project or the backlog item is decomposed into packet.
L solution ). Solving problems or difficulties usually leads to changes.
L risk ). Risks that affect project success should be tracked and evaluated continuously and adjusted accordingly. The risk assessment results will affect all other controls. SCRUM defines six conceptual variables for Risk Assessment: user needs, time pressure, competition, quality, vision and available resources.
These controls are used for evaluation and trade-offs at all stages of SCRUM, with managers focusing on managing backlogs and developers dealing with changes and difficulties. All personnel manage problems, risks, and measures together.
Root
Continuous Measurement, evaluation, and trade-offs of control items, especially risks. On the one hand, the plan and progress (at the end of each Sprint) are constantly adjusted to ensure the business objectives of the product.
The work task Backlog dynamically sorts the priorities. The development team always first develops the highest priority Backlog items, which ensures the most reasonable use of resources. In addition, SCRUM emphasis
The importance of the volume (using the standard function point measurement method). By measuring the productivity in each Sprint, the plan and progress will become more and more accurate.
(2) project organization.
The project team consists of full-time developers, marketing personnel, sales personnel, and users related to the delivered product. Set up the following groups:
L Project Management Group. Led by the product manager, including the chief designer, SCRUM team lead, marketing and sales staff and typical users.
L
Several SCRUM groups. Team Lead (SCRUM
Master. Each group is cross-disciplinary (usually including developers, document personnel, quality control personnel or user representatives), usually 3 ~ 7 members for full communication within the group. Group's
It is best to divide the data based on the Assigned Problem package or Backlog, but also the system hierarchy (based on the hierarchy in the architecture )..
When the number of project teams increases, you can create another Management Group (SCRUM of SCRUM) on top of the Management Group to apply the SCRUM method to large projects.
(3) control during the Sprint.
During the sprint, scrum teams should try to avoid external interference (new backlog tasks cannot be added, and the backlogs generated in the group can be placed in the backlog list of the entire project, can also be solved in this Sprint), so that the team members concentrate on the current work, so that they work on the edge of chaos.
To prevent the project team from getting into chaos during the sprint, scrum takes two measures:
L scrum meeting ). Monitor and stimulate group behaviors. The meeting is held in the same place every day during the sprint and is hosted by the scrum master. At the meeting, the scrum master raised three questions for each group member:
1) How was the progress of yesterday's work.
2) Have you encountered any difficulties or obstacles.
3) Today's work plan.
After the meeting, the scrum master will focus on removing obstacles, and the team members will carry out the development on that day.
L sprint review meeting. After the review, employees are encouraged based on their work scores.
3.2.3 practical effects and development direction of the scrum method:
Scrum
In practice, productivity is greatly increased (6 times higher, according to capers Jones of the software productivity Organization), and there is a "intermittent balance" (punctuated
Equilibrium) phenomenon (similar to the evolution of things in nature, which mutates at the Interchange after a relatively balanced period of independent and parallel development)
After the sprint development, software products experienced significant changes during the sprint review. The recent trend of the scrum method is to learn from the XP method.