AWS cloud migration. The continuity and even the survival of any company's business operations heavily depend on the reliability of its IT infrastructure. However, in today's context, no on-premise architecture can fulfill the required conditions.
Table of contents
Embracing Cloud Solutions for Resource Optimization
Drivers for Cloud Migration
Business Outcomes after Migration
AWS Migration Acceleration Program (MAP)
MAP AWS Benefits
Migration Approach: Lift-and-Shift, Replatforming, or Refactoring
In conclusion
Presently, this challenge has become a major catalyst for significant transformations in how clients perceive and adopt cloud services. Particularly, internet-based businesses, financial institutions, logistics companies, and other enterprises are keenly experiencing the necessity to swiftly scale their computing capabilities while minimizing additional costs.
Embracing Cloud Solutions for Resource Optimization
Not too long ago, the concept of "cloud services" was novel and unfamiliar to the majority of companies. Businesses were accustomed to relying on their own infrastructure, considering it sufficiently reliable and secure. However, they encountered issues that were either extremely challenging or practically unsolvable within their local data centers. The primary problem was the fluctuating availability of computing resources, with the occasional excess or shortage. Accurately estimating the required resources necessitated lengthy planning, and various types of businesses faced periods of significantly increased service load throughout the year.
For example, take any well-known online store. Each new promotion, marketing campaign, or product discount triggered a substantial influx of users, putting considerable strain on the servers running the platform.
This presented two core challenges: first, rapidly scaling the service to handle the increased load, and second, dealing with resource constraints when physical resources were insufficient. Creating service copies and employing load balancers proved to be more efficient and feasible with a microservices architecture.
Nonetheless, addressing the resource scarcity issue was more intricate, as acquiring new servers quickly was not a viable option. In cases where long-term resource planning fell short, promptly adding capacity became almost an impossible task. Consequently, service unavailability and significant financial losses were common occurrences. Even in instances of precise resource planning, the majority of the acquired additional resources remained largely underutilized.
Here comes the flexibility of public clouds to the rescue. Utilizing cloud services allows companies to pay only for the resources they actually use within specific time frames, and they have the ability to scale their consumption up or down at any moment. People often try to compare the cost of purchasing a physical server with renting resources in the cloud based solely on CPU, RAM, and Storage metrics, which is not entirely accurate. Of course, in such cases, using the cloud may appear to be expensive. However, many factors are not taken into account in such a comparison, such as the cost of consumed electricity, the salaries of technical specialists who manage these resources, physical and fire safety, and so on.
📎 Ready to Accelerate Your Journey to the Cloud? Choose Gart as your trusted AWS migration partner for a seamless on-premise to AWS Cloud migration. Let's dive in!
Drivers for AWS Cloud Migration
Over the past few years, there has been a significant increase in companies' demand for cloud services, which is entirely logical considering the advantages that companies gain through AWS cloud migration. Businesses identify the following drivers that motivate them to migrate:
Establishing a resilient infrastructure
Gaining quick access to computing power and services
High level of flexibility in infrastructure management
Optimization and scalability
Leveraging innovative solutions such as IoT, ML, AI
Complexity and duration of implementing hardware solutions
Cost reduction through the use of cloud technologies
In summary, companies aspire to grow rapidly, enhance user experiences, implement digital transformation tools, and modernize their businesses. They reinvest the cost savings from infrastructure into developing their companies further.
Nearly every migration is a challenging undertaking.
Business Outcomes after Migration
Cloud technologies offer companies a range of advantages, including:
Cost reduction compared to on-premise solutions (31%)
Increased staff productivity and quick onboarding (62%)
Enhanced flexibility in implementing new services (75%)
However, migration projects for large companies are complex decisions that require a comprehensive approach, combining the application of specific services, methodologies, and expertise in chosen cloud technologies. Often, executing migration projects without proper management methodologies significantly complicates the process and substantially extends the project timelines.
At Gart, we transform the migration process into a well-managed and conscious journey by offering a proven methodology, as a leader among cloud providers, integrating technical solutions with the company's business objectives, and enhancing the competence of clients when working in cloud environments.
Moving forward, we will explore how to achieve a fast and effective migration to Amazon Web Services.
📎 Don't miss this opportunity to embrace the limitless possibilities of AWS Cloud with Gart by your side!. Contact Us
AWS Migration Acceleration Program (MAP)
For any organization, the key performance indicators for the successful implementation of new technologies typically revolve around stability, high availability, and cost-effectiveness. Hence, it is crucial to assess the company's IT infrastructure and business processes' readiness for cloud migration. To facilitate this process, AWS offers a specialized program called the AWS Migration Acceleration Program (MAP).
It is important to note that this program may not be applicable to all clients. For instance, migrating a single virtual server is unlikely to meet the requirements of this offer. However, for medium and large-scale companies seriously considering the adoption of cloud services, this program will be highly beneficial.
In addition to the comprehensive approach to AWS cloud migration, the MAP program provides clients with a significant discount on resource usage for a duration of three years. The program comprises three main stages:
Assessment
Mobilization (testing)
Migration and modernization.
Assessment
During the assessment stage, the officially authorized AWS MAP partner conducts an inventory of the client's existing systems to develop a conceptual architecture for their migration to the cloud. A comprehensive business case is created, outlining how the infrastructure will look after the migration, the estimated cost for the client, and when it is advisable to transition from virtual machines to services. All client requirements regarding availability, resilience, and security are taken into account. Additionally, an evaluation of existing licenses, such as Oracle or Microsoft, is performed to determine whether it is beneficial to migrate them to the cloud or opt for renting them directly from the platform.
As a result, the client receives exhaustive information about migration possibilities and potential cost savings in the cloud. In some cases, these savings can reach up to 70%. Typically, the assessment stage takes 3-6 weeks, depending on the project's complexity.
Mobilization
During the testing stage, a test environment is deployed in the cloud based on the developed architecture to verify the proposed solutions evaluated during the assessment phase.
Migration and modernization
After conducting all the tests, we move on to the final stage of the AWS MAP. At this stage, the production infrastructure is deployed in the cloud, and its optimization takes place. However, it's essential to continuously analyze and optimize the infrastructure on a regular basis.
MAP AWS Benefits
The AWS Migration Acceleration Program (MAP) offers several benefits, including:
Comprehensive Assessment
Clients receive a thorough evaluation of their IT infrastructure and business processes to assess readiness for AWS cloud migration.
Cost Savings
The program provides significant discounts on resource usage for three years, helping clients save costs during their migration journey.
Conceptual Architecture
A well-defined conceptual architecture is developed for the cloud migration, outlining the post-migration infrastructure and estimated costs.
License Optimization
Existing licenses, such as Oracle or Microsoft, are evaluated to determine the most cost-effective approach for their migration or rental on the cloud platform.
Test Environment
A test environment is set up in the cloud to validate the proposed solutions and ensure a smooth migration process.
Production Deployment and Optimization
After successful testing, the production infrastructure is deployed in the cloud and continuously optimized for performance and efficiency.
Regular Analysis and Optimization
The MAP ensures that infrastructure analysis and optimization are conducted regularly to maintain peak performance and cost-effectiveness.
Migration Approach: Lift-and-Shift, Replatforming, or Refactoring
Selecting the right migration approach is a crucial step in the cloud migration process. There are three primary migration approaches to consider:
Lift-and-Shift
This approach involves migrating applications and workloads to the cloud with minimal changes. It is a quick and straightforward method but may not fully leverage the benefits of cloud-native services.
Replatforming
Replatforming, also known as lift-tinker-and-shift, involves making some optimizations and adjustments to the applications to take advantage of cloud services while minimizing significant code changes.
Refactoring
This approach involves rearchitecting and reengineering applications to be cloud-native, fully leveraging the benefits of cloud services, scalability, and agility.
The selection of the migration approach depends on factors such as application complexity, business goals, cost considerations, and the desired level of cloud-native functionality. Each approach has its trade-offs, and the right choice will depend on the specific needs and priorities of the organization's cloud migration journey.
In Conclusion: AWS Cloud Migration
If your organization is considering migrating to AWS and wants a smooth and efficient migration process, look no further than Gart. We can provide you with a comprehensive assessment, a well-defined migration plan, and cost-effective solutions. Whether you choose the lift-and-shift, replatforming, or refactoring approach, our team will guide you every step of the way to ensure a successful cloud migration. Take the next step towards unlocking the full potential of AWS and contact Gart today for a seamless transition to the cloud.
Unlock the secrets to smart cloud cost management with our comprehensive guide. Learn about different cloud cost models, optimization tips, and tools to make informed decisions. Whether you're a startup or an enterprise, master the art of cost-effective cloud computing.
Table of contents
Different Cost Models in Cloud Computing
Pay-As-You-Go (PAYG) Cloud Model
Reserved Instances (RIs)
Spot Instances
More Cloud Cost Models
Cost Estimation Tools
Ever wondered how companies manage their expenses when using the cloud? It's a bit like choosing a phone plan – you want one that fits your needs without breaking the bank.
Different Cost Models in Cloud Computing
Cloud computing has revolutionized the way businesses operate, offering scalability, flexibility, and cost-efficiency like never before. Each model comes with its own set of advantages and trade-offs, making it essential to choose the right one for your organization's needs. Here's a breakdown of the primary cloud cost models:
Pay-As-You-Go (PAYG)
Reserved Instances (RIs)
Spot Instances
On-Demand Instances
Reserved Capacity
Serverless and Consumption-based Pricing
Pay-as-you-goReserved InstancesSpot InstancesDefinitionPay for what you use, no upfront commitmentReserved instances with upfront paymentsSpare capacity instances offered at discounted ratesAdvantagesFlexibility, no upfront costsCost savings, predictabilityCost-effective for non-time- sensitive tasksConsiderationsCosts can add up quickly if not monitoredUpfront payment, limited flexibility in instance typesInstances can be terminated if reclaimed by the cloud
Pay-As-You-Go (PAYG) Cloud Model
The Pay-As-You-Go (PAYG) cloud model is like a "pay only for what you use" approach to cloud computing. In this model, you're billed based on your actual usage of cloud resources, such as virtual machines, storage, and data transfer. There's no upfront commitment or long-term contract. Instead, you're charged on an hourly or per-second basis, depending on the cloud provider.
Advantages of PAYG
PAYG offers unmatched flexibility. You can easily scale resources up or down to meet changing demands. Need more computing power during a busy season? No problem. PAYG allows you to spin up additional instances as needed and scale them down when the rush is over.
Unlike other models like Reserved Instances, PAYG doesn't require any upfront payments or commitments. You start using resources immediately and pay only for what you consume, making it cost-effective for startups and projects with unpredictable workloads.
PAYG is an excellent entry point for businesses new to cloud computing. You can experiment, test, and develop without the burden of a long-term financial commitment. This allows you to explore the cloud's potential without major financial risk.
Challenges and Considerations
Cost Management
While PAYG provides flexibility, it can also lead to unexpected costs if resources aren't managed effectively. Teams need to actively monitor usage and optimize their cloud environment to avoid overspending.
Unpredictable Costs
For organizations with highly variable workloads, it can be challenging to predict monthly expenses accurately. This unpredictability can make budgeting a bit trickier.
Limited Cost Savings
Although PAYG is cost-effective for short-term projects and experimentation, it may not provide the same level of savings as Reserved Instances for long-term, stable workloads.
Real-world Examples
Many startups leverage PAYG to launch their services. They can begin small, assess user demand, and then scale their resources as their user base grows, all without a significant upfront investment.
E-commerce companies often experience seasonal spikes in traffic during holidays. They can use PAYG to handle increased demand during these periods and then scale back afterward to avoid unnecessary costs.
Development and testing environments are ideal candidates for PAYG. Developers can create instances when needed, develop and test their applications, and then terminate resources to stop incurring costs when not in use.
💡 Read more: Optimizing Costs and Operations for Cloud-Based SaaS E-Commerce Platform
Reserved Instances (RIs)
Reserved Instances (RIs) are a strategic cost-saving tool in cloud computing. Unlike the Pay-As-You-Go model, where you pay for resources by the hour or second with no commitments, RIs involve a commitment to a specific instance type and region for a predetermined duration, usually one or three years. This commitment results in significantly reduced hourly rates compared to on-demand pricing.
There are two primary types of RIs:
Standard RIs
These offer the highest level of cost savings but are less flexible. You commit to a specific instance type and operating system within a particular region for the chosen term. They are best suited for stable workloads with predictable resource requirements.
Convertible RIs
Convertible RIs provide more flexibility. While you still commit to a specific instance type and region, you have the option to change the instance type, family, or operating system during the reservation term. This versatility makes them suitable for workloads that may evolve or need adjustments over time.
Benefits of using RIs
RIs can result in substantial cost reductions, often up to 75% compared to on-demand prices. This makes them an attractive choice for businesses with steady workloads.
RIs guarantee access to cloud resources even during peak times. You have reserved capacity, ensuring your applications run smoothly without interruptions.
With RIs, you can accurately predict your long-term cloud costs, making budgeting and financial planning more manageable.
📎 Ready to Revolutionize Your Deployment Process? Looking for expert guidance to choose the right cloud cost model? Reach out to Gart, our cloud cost optimization specialist, and make the most of your cloud investments.
Cost Optimization Strategies with RIs
To make the most of Reserved Instances, consider these strategies:
Identify Stable Workloads
RIs are most effective when applied to stable workloads with predictable resource needs. Analyze your usage patterns to determine which instances are good candidates.
Mix and Match
Use a combination of Standard and Convertible RIs to balance cost savings and flexibility. Convertible RIs are useful for workloads that may change over time.
Utilize Third-Party Tools
Cloud cost management tools can help identify RI purchase recommendations and ensure that RIs are used effectively.
Use Cases and Examples
Companies with consistently high web traffic can reserve instances for their web servers, ensuring they have the necessary capacity to handle user requests efficiently.
Reserved Instances are ideal for database servers that require constant uptime and predictable performance. They provide cost savings while maintaining data availability.
Large enterprises running resource-intensive applications can benefit from RIs by reducing ongoing operational costs.
E-commerce businesses can reserve instances during peak shopping seasons to handle increased traffic while enjoying substantial cost savings.
Use CasePay-As-You-Go (PAYG)Reserved Instances (RIs)Startups✔️ Flexible for growth✔️ Cost savings for stable workloadsVariable Workloads✔️ Easily scale up/down❌ May not suit highly fluctuating workloadsPredictable Workloads❌ Costs can add up✔️ Cost-effective for steady resource needsExperimentation✔️ No upfront costs❌ Requires upfront commitmentSeasonal Traffic✔️ Scale resources✔️ Plan ahead and save on costsDevelopment Environments✔️ Flexibility❌ May not be the most cost-efficientData Analysis✔️ Quick access to power❌ Might overpay for stable analysisPredictable Performance❌ Costs can vary widely✔️ Guaranteed capacity and cost savingsLarge Enterprises✔️ Scalability✔️ Long-term cost predictabilityBig Data Processing✔️ Scale for big tasks✔️ Plan and save on long-running jobsThis table visually compares use cases of the Pay-As-You-Go (PAYG) cloud model and Reserved Instances (RIs) to help you understand which model might be more suitable for various scenarios.
Spot Instances
Spot Instances are a unique and cost-effective cloud computing model offered by many cloud service providers, including Amazon Web Services (AWS), Google Cloud Platform (GCP), and Microsoft Azure. They are designed for workloads that are flexible and can tolerate interruptions. Spot Instances allow you to access spare cloud computing capacity at significantly reduced prices compared to on-demand instances.
How Spot Instances Work
Spot Instances work on the principle of surplus cloud capacity. Cloud providers often have more resources available than are currently in use. To make use of this excess capacity, they offer it to customers at a much lower cost through Spot Instances. Here's how it works:
Users can request Spot Instances, specifying their instance type, region, and maximum price they are willing to pay per hour.
Cloud providers determine Spot instance prices based on supply and demand. When your bid price exceeds the current market price, your Spot Instances are provisioned.
Spot Instances can be terminated with very little notice, usually with a two-minute warning. This is because if a higher-paying customer requires the resources, the Spot Instances are preempted.
The primary advantage of Spot Instances is cost savings. Spot Instances typically cost a fraction of the price of on-demand instances. Organizations can achieve significant cost reductions, especially for workloads that can be interrupted or spread across multiple instances for fault tolerance.
Best Practices and Considerations
To make the most of Spot Instances while managing their inherent volatility, consider these best practices and considerations:
Fault Tolerance
Design your applications to be fault-tolerant. Distribute workloads across multiple Spot Instances and regions to mitigate the risk of termination.
Auto Scaling
Implement auto-scaling and monitoring to automatically launch replacement instances if Spot Instances are terminated.
Use Cases
Identify workloads that can leverage Spot Instances, such as batch processing, data analysis, rendering, and testing environments.
Bid Strategies
Be mindful of your bid price. Set it competitively to ensure resource availability while maintaining cost savings.
Instance TypesBe flexible with your choice of instance types. Different types may have varying availability and pricing.
Use Cases and Industries that Benefit
Spot Instances are ideal for data processing, analytics, and machine learning workloads, where large amounts of computational power are required intermittently.
Research institutions and scientific projects can use Spot Instances to perform complex simulations and calculations cost-effectively.
Rendering, transcoding, and video processing tasks in the media and entertainment industry can benefit from the scalability and cost savings of Spot Instances.
Development and testing environments can utilize Spot Instances to keep costs low while providing developers with the resources they need.
Financial modeling and risk analysis tasks can take advantage of Spot Instances to perform intensive calculations at a lower cost.
More Cloud Cost Models
On-Demand Instances
With on-demand instances, you pay by the hour or second without any long-term commitment.
Advantages: No upfront costs, maximum flexibility.
Considerations: Usually more expensive than RIs, not suitable for steady workloads.
Reserved Capacity
This model involves pre-purchasing capacity for services like databases or storage.
Advantages: Guaranteed availability, potential cost savings for predictable workloads.
Considerations: Upfront payment, limited flexibility.
Serverless and Consumption-based Pricing
Serverless computing charges you based on actual usage, making it cost-effective for sporadic workloads.
Advantages: Efficient for small, intermittent tasks, and automatically scales.
Considerations: May not be suitable for all applications, harder to predict costs.
Cost Estimation Tools
In the complex world of cloud computing, keeping tabs on your expenses can be challenging. This is where cost estimation tools come into play. These tools are your financial compass in the cloud, helping you navigate costs, optimize spending, and make informed decisions.
AWS Cost Explorer: This tool from Amazon Web Services (AWS) provides cost analysis and visualization, helping users understand and control their AWS spending.
Google Cloud Cost Management: Google Cloud Platform (GCP) offers a suite of cost management tools, including Cost Explorer and Billing Reports, to help users monitor and optimize their GCP expenses.
Azure Cost Management and Billing: Microsoft's Azure offers robust cost management features, including budgeting, forecasting, and spending analysis.
CloudHealth by VMware: CloudHealth offers a comprehensive cloud management platform with cost optimization, governance, and security features. It supports multiple cloud providers.
FinOps Foundation: While not a specific tool, the FinOps Foundation is a community-driven initiative that provides best practices, standards, and resources for cloud financial management.
Here are some additional factors to consider when choosing a cloud cost model:
Your budget: How much are you willing to spend on cloud computing?
Your workload: What type of workloads will you be running on the cloud?
Your flexibility needs: Do you need to be able to scale your resources up or down quickly?
Your risk tolerance: Are you willing to take the risk of having your spot instances terminated?
You see, building software is a lot like cooking your favorite dish. Just as you add ingredients to make your meal perfect, software developers consider various elements to craft software that's top-notch. These elements, known as "software quality attributes" or "non-functional requirements (NFRs)," are like the secret spices that elevate your dish from good to gourmet.
Table of contents
Questions that Arise During Requirement Gathering
Types of Requirements
Understanding NFRs: Mandatory vs. Not Mandatory
Expressing NFRs: a Unique Challenge
The Impact of NFRs on Design and Code
Real-World Examples of NFRs
The relationship between Software Quality Attributes and NFRs
Questions that Arise During Requirement Gathering
When embarking on a software development journey, one of the crucial initial steps is requirement gathering. This phase sets the stage for the entire project and helps in shaping the ultimate success of the software. However, as you delve into this process, a multitude of questions arises
1. Is this a need or a requirement?
Before diving into the technical aspects of a project, it's essential to distinguish between needs and requirements. A "need" represents a desire or a goal, while a "requirement" is a specific, documented statement that must be satisfied. This differentiation helps in setting priorities and understanding the core objectives of the project.
2. Is this a nice-to-have vs. must-have?
In the world of software development, not all requirements are equal. Some are critical, often referred to as "must-have" requirements, while others are desirable but not essential, known as "nice-to-have" requirements. Understanding this distinction aids in resource allocation and project planning.
3. Is this the goal of the system or a contractual requirement?
Requirements can stem from various sources, including the overarching goal of the system or contractual obligations. Distinguishing between these origins is vital to ensure that both the project's vision and contractual commitments are met.
4. Do we have to program in Java? Why?
The choice of programming language is a fundamental decision in software development. Understanding why a specific language is chosen, such as Java, is essential for aligning the technology stack with the project's needs and constraints.
Types of Requirements
Now that we've addressed some common questions during requirement gathering, let's explore the different types of requirements that guide the development process:
Functional Requirements
Functional requirements specify how the system should function. They define the system's behavior in response to specific inputs, which lead to changes in its state and result in particular outputs. In essence, they answer the question: "What should the system do?"
Non-Functional Requirements (Constraints)
Non-functional requirements (NFRs) focus on the quality aspects of the system. They don't describe what the system does but rather how well it performs its intended functions.
Source: https://iso25000.com/index.php/en/iso-25000-standards/iso-25010
Functional requirements are like verbs
– The system should have a secure login
NFRs are like attributes for these verbs
– The system should provide a highly secure login
Two products could have exactly the same functions, but their attributes can make them entirely different products.
AspectNon-functional RequirementsFunctional RequirementsDefinitionDescribes the qualities, characteristics, and constraints of the system.Specifies the specific actions and tasks the system must perform.FocusConcerned with how well the system performs and behaves.Concentrated on the system's behavior and functionalities.ExamplesPerformance, reliability, security, usability, scalability, maintainability, etc.Input validation, data processing, user authentication, report generation, etc.ImportanceEnsures the system meets user expectations and provides a satisfactory experience.Ensures the system performs the required tasks accurately and efficiently.Evaluation CriteriaUsually measured through metrics and benchmarks.Assessed based on whether the system meets specific criteria and use cases.Dependency on FunctionalityIndependent of the system's core functionalities.Dependent on the system's functional behavior to achieve its intended purpose.Trade-offsBalancing different attributes to achieve optimal system performance.Balancing different functionalities to meet user and business requirements.CommunicationOften involves quantitative parameters and technical specifications.Often described using user stories, use cases, and functional descriptions.
Understanding NFRs: Mandatory vs. Not Mandatory
First, let's clarify that Functional Requirements are the mandatory aspects of a system. They're the must-haves, defining the core functionality. On the other hand, Non-Functional Requirements (NFRs) introduce nuances. They can be divided into two categories:
Mandatory NFRs: These are non-negotiable requirements, such as response time for critical system operations. Failing to meet them renders the system unusable.
Not Mandatory NFRs: These requirements, like response time for user interface interactions, are important but not showstoppers. Failing to meet them might mean the system is still usable, albeit with a suboptimal user experience.
Interestingly, the importance of meeting NFRs often becomes more pronounced as a market matures. Once all products in a domain meet the functional requirements, users begin to scrutinize the non-functional aspects, making NFRs critical for a competitive edge.
Expressing NFRs: a Unique Challenge
While functional requirements are often expressed in use-case form, NFRs present a unique challenge. They typically don't exhibit externally visible functional behavior, making them difficult to express in the same manner.
This is where the Quality Attribute Workshop (QAW) comes into play. The QAW is a structured approach used by development teams to elicit, refine, and prioritize NFRs. It involves collaborative sessions with stakeholders, architects, and developers to identify and define these crucial non-functional aspects. By using techniques such as scenarios, trade-off analysis, and quality attribute scenarios, the QAW helps in crafting clear and measurable NFRs.
Good NFRs should be clear, concise, and measurable. It's not enough to list that a system should satisfy a set of NFRs; they must be quantifiable. Achieving this requires the involvement of both customers and developers. Balancing factors like ease of maintenance versus adaptability is crucial in crafting realistic performance requirements.
There are a variety of techniques that can be used to ensure that QAs and NFRs are met. These include:
Unit testing: Unit testing is a type of testing that tests individual units of code.
Integration testing: Integration testing is a type of testing that tests how different units of code interact with each other.
System testing: System testing is a type of testing that tests the entire system.
User acceptance testing: User acceptance testing is a type of testing that is performed by users to ensure that the system meets their needs.
The Impact of NFRs on Design and Code
NFRs have a significant impact on high-level design and code development. Here's how:
Special Consideration: NFRs demand special consideration during the software architecture and high-level design phase. They affect various high-level subsystems and might not map neatly to a specific subsystem.
Inflexibility Post-Architecture: Once you move past the architecture phase, modifying NFRs becomes challenging. Making a system more secure or reliable after this point can be complex and costly.
Real-World Examples of NFRs
To put NFRs into perspective, let's look at some real-world examples:
Performance: "80% of searches must return results in less than 2 seconds."
Accuracy: "The system should predict costs within 90% of the actual cost."
Portability: "No technology should hinder the system's transition to Linux."
Reusability: "Database code should be reusable and exportable into a library."
Maintainability: "Automated tests must exist for all components, with overnight tests completing in under 24 hours."
Interoperability: "All configuration data should be stored in XML, with data stored in a SQL database. No database triggers. Programming in Java."
Capacity: "The system must handle 20 million users while maintaining performance objectives."
Manageability: "The system should support system administrators in troubleshooting problems."
The relationship between Software Quality Attributes and NFRs
As and NFRs are both important aspects of software development, and they are closely related.
Software Quality Attributes are characteristics of a software product that determine its quality. They are typically described in terms of how the product performs, such as its speed, reliability, and usability.
NFRs are requirements that describe how the software should behave, but do not specify the specific features or functions of the software. They are typically described in terms of non-functional aspects of the software, such as its security, performance, and scalability.
In other words, QAs are about the quality of the software, while NFRs are about the behavior of the software.
The relationship between QAs and NFRs can be summarized as follows:
QAs are often used to measure the fulfillment of NFRs. For example, a QA that measures the speed of the software can be used to measure the fulfillment of the NFR of performance.
NFRs can sometimes be used to define QAs. For example, the NFR of security can be used to define a QA that tests the software for security vulnerabilities.
QAs and NFRs can sometimes conflict with each other. For example, a software product that is highly secure might not be as user-friendly.
It is important to strike a balance between Software Quality Attributes and NFRs. The software should be of high quality, but it should also meet the needs of the stakeholders.
Here are some examples of the relationship between QAs and NFRs:
QA: The software must be able to handle 1000 concurrent users.
NFR: The software must be scalable.
QA: The software must be able to recover from a system failure within 5 minutes.
NFR: The software must be reliable.
QA: The software must be easy to use.
NFR: The software must be usable.
