Non-Functional Requirements of a Software Project Introduction:
“Non-functional requirements (NFRs) is said to
Me attributes of a system.”
Non-functional requirements also keep to maintain functional requirements of system in line.
The attribute which make a product or system affordable, come under relax able mode, easy to use as compare to other one or accessible.
Non-functional require attribute fulfil user need. If a software system failing to meet all NFRs attributes can give result of unsatisfication of users.
NFRs allows user to serve or impose restrictions or constraints on critical design of software system across various backlogs.
As compare with functional requirements who give idea that what a software system or project must perform or do, non-functional requirements who guide how they perform their performance.
Although non-functional requirements may come under subtler but they still much important as functional qualities.
NFRs is general characteristics, feature or qualities which impact a user experience or expectation.
Different types of NFRs
Although there are many types of NFRs which support how a software system perform or meet their feature, qualities and characteristics which affect the user experience.
Here we discussed some attributes of NFRs which show simply resistance along their software project or system:
• Scalability
• Maintainability
• Usability
• Reliability
• Availability
• Performance ability
• Capacity
• Security
• Regulatory
• Environmental
• Data integrity
• Recoverability
• Manageability
• Portability
- Interoperability
Requirements
• Scalability requirements
• Maintainability requirements
• Usability requirements
• Reliability requirements
• Availability requirements
• Performance requirements
• Capacity requirements
• Security requirements
• Regulatory requirements
• Regulatory requirements
• Environmental requirements
• Data integrity requirements
• Recoverability requirements
• Portability requirements
• Interoperability requirements
Detail of requirements:
ü Scalability
Scalability is feature, quality or character of any organization, project, software, system, model, etc. that reveals its capacity or quality to perform well under increased or overloaded workload.
A software or function that perform good will be able to maintain its capacity, efficiency or performance or some time increased or expand their scope or demand in operational regions.
If we talk about how scalability impact or perform in region of financial marketing, we said that scalability improve financial institute guideline or directly impact the profit margin through which sales demand expand or increased.
ü Maintainability
Maintainability is ability or degree of system or function which retained in, to restore to specific condition. Its main purpose is to retain or restored functional failure to its normal operating condition or performance to maintain its capacity or performance.
Trained team, standard equipment, planned or drawing and checklists effect the maintainability of any system or function.
ü Usability
Usability is degree to measure how a specific user in specific context can use a specific product or system to meet or achieve its goal or aim with 100% satisfaction or efficiency.
People often confuse to mix usability concept to experience of user or ease of use. Usability is part of user experience design.
Usability contain ease of learning, efficiency, effectiveness and engagement.
ü Reliability
Reliability is quality of function or system that perform intended function in a specific time period or operate or run to their normal operating behavior without any fault or failure.
Reliability includes following terms;
• Specific time period
• Intended function
• Specific conditions
• Satisfactory dependability
- Probability
• Availability
Availability, in term of software or computer system, means of user to collect information or resources in specific location and in right format.
Availability is a part of five pillars of information assurance.
• Five pillars;
• Integrity
• Availability
• Confidentiality
• Non-repudiation
Availability is direct or indirect effect users, if regular system non-functionally occur which affect availability.
ü Performance
Performance is any act of performance, physical action, accomplishment, any action which give good result count in well performance of any system or function.
As you know any bad performance of anything or system direct spoil its reputation or capability.
While in other terms good performance not impacts good reviews also increases or expand scope or demand in workload.
ü Capacity
Capacity is feature of absorbing, receive or containing any volume, numbers or anything.
For example, a window has ability or capacity to receive 15 GB data.
ü Security
Term security means financial instrument that maintain some type of monetary value.
Financial instruments are may be fungible or tradable.
Commonly three types of securities;
• Equity securities
• Debt securities
• Hybrids securities
ü Environmental requirements
Environmental requirements including any applicable or hold able laws, orders, permits, statutes. Rules and regulations.
In the other words environmental requirements is all laws and rules and regulation that meet or maintain human health or environmental factors such as plants, pollutants factors etc.
ü Data integrity
Data integrity refers to completeness of data. It also include overall accuracy and consistency of data.
They said to be safety of data in term of service and security.
It also ensure that data which a specific user use, is under security factor which means our data is safe from any out sides harm forces.
ü Recoverability
Recoverability is ability or quality to recover information, money, or data.
For example, if a website is upgraded and user paid it then if it does not satisfied with websites content or performance they want to recover their money from money back guarantee.
The same thing is occur with data. You also recover your data as well.
ü Portability
Portability is quality or ability to measure how fast an application is transferred from one environment of computer to other one.
Its measure how much fast a computer software to transfer data or applications.
In the other words we can say that its meaning is how fast a system work in changing environment.
ü Manageability
Manageability is quality of software system to easily control by means of self-control or techniques in term of external controls.
Manageability include four categories;
• Health alerting
• Control
• Updates
- Discovery
ü Interoperability
Interoperability is feature of computerized system or product to exchange or transfer information one another through implementation without any warning and restrictions.
It’s also include sharing unrestricted data and application through one medium to other one.
Example of NFRs
Here some examples of non-functional requirements;
• Loading time of each page is must be under 2 seconds.
• Changing of password immediately after 1st login.
• Restriction for upload your salary information.
• Take a recording of any unsuccessful attempt of user to access data.
• Capable of handling 20 million user with well performance.
• Having Portable software
• Information privacy
• User provide electrical signature before loading new page.
Advantages of NFRs
Following advantages given by non-functional requirements;
• Insurance of using or follow legal rules and regulation.
• Specification of attributes of software system.
• They ensure performance, scalability, reliability and much more qualities.
• Construction of security policy.
• Insurance of minimized cost factor and user good experience.
Disadvantages of NFRs
Drawbacks/disadvantages of non-functional requirements are following;
• Effecting high-level software system.
• Increased cost during software high-level design because require special consideration.
• Do not usually map software sub-system.
• Tough to change or modify non-functional attributes once passes through design phase.
Recommendation
Before finishing up non-functional requirements topic I think recommendation and modification discussion through which we can make more good documentation.
Here’s some detail;
Ø Measurable and testable;
The documentation which you do or want, also need measure units and testing. The measure units used, give you a success and failure level as well.
Through which you can measure and test at which level your documentation reach.
Ø Requirements
Complex interfacing need such requirements.
If user do not use product one part setting performance limitation.
Ø Business objective
Try to link or connects your business objective with NFRs because sometimes availability not impact your sales.
Ø Third part limitation
If you use API third part must return data slower.
Ø Design limitation
Refectory legacy code, current design fully reworked to meet requirements.
Summery
As we know, functional requirements are important, but we say that non-functional requirements are also important in maintain your software system as well.
So maintain functional requirements of system, also maintain its non-functional requirements to make your system efficient or successful.
A functional requirements help to know what a software system do, at the same time non-functional system support to know that how a software performed.
In this discussion we learn how different attributes of non-functional requirements impact direct or indirect software system.
In financial marketing, same attributes also impact the profit margin and increased or expand the sales numbers. Through which we can earn more cost or other margins.
As we discussed today, the non-function give good and many benefits to our system, but at the same time they also give some drawbacks. Through which our system effected and user experience also affected through which.
