This article is a collection of notes and references from other web sites for the self study of Single Page Applications and Angular. The list of source web sites referred are mentioned in the “References” section of this article.
“Begin with the end in mind”
- Maintenance and support will continue for the life of your software system. A significant portion of the system’s life-cycle budget will be consumed by these tasks. In fact, experts estimate that Maintenance can eventually account for 40 to 80% of the total project cost.
- Software does not “wear out” but it will become less useful as it gets older, plus there WILL always be issues within the software itself.
- Software maintenance cost is derived from the changes made to software after it has been delivered to the end user.
What is Maintenance?
This phase of the software lifecycle consists of the tasks required to keep your system operational after it is delivered into Production.
The different types of maintenance tasks are described as:
- Corrective – Updates that are required to correct or fix problems. (generally 20% of software maintenance costs)
- Perfective – Modifications that enhance or improve the functionality or performance of the software. This includes new user requirements. – costs due to improving or enhancing a software solution to improve overall performance (generally 5% of software maintenance costs)
- Adaptive – Software modifications that are required due to environmental changes (eg. upgrade to operating system) – costs due to modifying a software solution to allow it to remain effective in a changing business environment (25% of software maintenance costs)
- Preventative – This corrects potential flaws or problems in the software before they become effective.
- Enhancements – costs due to continuing innovations (generally 50% or more of software maintenance costs) Same as Perfective ?
What is Support?
Support refers to the assistance given to users to address their problems and queries after system implementation.
Key parameters considered while estimating the efforts required are as below
- The industry and application type
- Size of the application
- Platform Types.
- Programming language used
- Effort spent on different maintenance activities
- Effort spent on different support activities
- The number and types of defects found during the maintenance period
- Average time is taken to repair defects
- Calls to Help Desk
- Team size
Approaches to take over projects in production
- The term elicitation is used in books and research to raise the fact that good requirements cannot just be collected from the customer, as would be indicated by the name requirements gathering. Requirements elicitation is non-trivial because you can never be sure you get all requirements from the user and customer by just asking them what the system should do OR NOT do (for Safety and Reliability). Requirements elicitation practices include interviews, questionnaires, user observation, workshops, brainstorming, use cases, role playing and prototyping
Detect patterns and the general structure of an application at a high level
- Reverse analysis the source code
The architecture tools and Static Code Analysis in Visual Studio Ultimate help us to visualize the organization, relationships, design patterns and behavior of existing applications
- Generate sequence diagrams from the existing code and get required interfaces for each component
- Sequence diagrams help to asses the impact of changes
Improve productivity and quality through Automation
- Automated Live Unit Testing with VS
- Automatically runs the impacted unit tests in the background as you type and provides real-time feedback
Use Agile or Iterative Waterfall SDLC
- Produces working software early during the lifecycle
- The focus is on delivering a sprint of work
- Deliver series of valuable/shippable features/projects
- Low risks factors as the risks can be identified and resolved during each iteration.
- if one project goes wrong, it would not impact another project
- More flexible as scope and requirement changes can be implemented at low cost
- Size of each application or module
|Application||Number of Modules||Number of
|Number of Scheduled Batches||Number of Integrations to External applications|
The number and types of defects found in a year
|Classification||Priority||No of issues found|
List of different .NET languages, Databases used with the applications.
|Technology / Languages||Number of applications|
List of different .NET frameworks used with the applications.
|Technology / Languages||Number of applications|
|ASP.NET – Web Forms|
|ASP.NET – MVC|
|Any other technologies|
Third-party applications or packages integrated with the applications
|Third Party integrations||Number of applications|
|CRM (Siebel, Vantive, Remedy, SharePoint, Documentum etc.)|
|BI / OLAP / DW Tools
(ETL, Data Stage, Sagent, Informatica,
SAS, Ab Initio)
|ERP Skills (Peoplesoft, SAP,
Oracle Applications etc.)
Software development life cycle models used
|SDLC||Number of applications||Number of releases in a year|
|Any other SDLC methods|
Type of Integration and deployment methods used (to estimate the efforts to deliver the build to different environments
|Integration and Deployment||Number of applications|
|Automated deployments only|
|Manual Integration and deployment|
Availability of the documents in English
- Architecture documents, HLD, LLD, User guides, deployment documents etc
- SDLC Models
- Visual Studio Architecture Tooling Guide Scenarios