Explanation: The AWS Well-Architected Framework helps you understand the pros and cons of decisions you make while building systems on AWS. By using the Framework, you will learn architectural best practices for designing and operating reliable, secure, efficient, and cost-effective systems in the cloud. The Framework consists of five pillars: operational excellence, security, reliability, performance efficiency, and cost optimization2.

Explanation: Spot Instances are spare Amazon EC2 instances that are available at up to 90% discount compared to On-Demand prices. They are suitable for workloads that can tolerate interruptions, such as batch processing, data analysis, and testing. Spot Instances are allocated based on the current supply and demand, and can be reclaimed by AWS with a two-minute notice when the demand exceeds the supply5. Convertible Reserved Instances are a type of Reserved Instances that provide a significant discount (up to 54%) compared to On-Demand prices and a capacity reservation for Amazon EC2 instances. They are available in 1-year or 3-year terms and allow users to change the instance family, size, operating system, or tenancy during the term. Standard Reserved Instances are another type of Reserved Instances that provide a larger discount (up to 75%) compared to On-Demand prices and a capacity reservation for Amazon EC2 instances. They are available in 1-year or 3-year terms and do not allow users to change the instance attributes during the term. Dedicated Hosts are physical servers with Amazon EC2 instance capacity fully dedicated to the user’s use. They are suitable for users who have specific serverbound software licenses or compliance requirements.

Explanation: The combination of AWS services that the application can use to migrate to a microservices-based application are Amazon Simple Queue Service (Amazon SQS) and AWS Lambda. Amazon SQS is a fully managed message queuing service that enables customers to decouple and scale microservices, distributed systems, and serverless applications. The application can use Amazon SQS to send, store, and receive messages between the microservices, ensuring that each message is processed only once and in the right order. AWS Lambda is a serverless compute service that allows customers to run code without provisioning or managing servers. The application can use AWS Lambda to create and deploy microservices as functions that are triggered by events, such as messages from Amazon SQS. AWS Migration Hub, AWS AppSync, and AWS Application Migration Service are not the best services to use for migrating to a microservices-based application. AWS Migration Hub is a service that provides a single location to track the progress of application migrations across multiple AWS and partner solutions. AWS AppSync is a service that simplifies the development of GraphQL APIs for real-time and offline data synchronization. AWS Application Migration Service is a service that enables customers to migrate their on-premises applications to AWS without making any changes to the applications, servers, or databases.

Explanation: Amazon EC2 Spot Instances let you take advantage of unused EC2 capacity in the AWS cloud. Spot Instances are available at up to a 90% discount compared to On- Demand prices. You can use Spot Instances for various stateless, fault-tolerant, or flexible applications such as big data, containerized workloads, CI/CD, web servers, high-performance computing (HPC), and other test & development workloads. Spot Instances are well-suited for massively parallel computations, as they can provide large amounts of compute capacity at a low cost, and can be interrupted with a two-minute notice3.

Explanation: Rightsizing all the EC2 instances that are used in the deployment is the best way to run the workload in the most cost-effective way. Rightsizing means choosing the optimal instance type and size for the workload based on the performance and capacity requirements. Rightsizing helps to avoid over-provisioning or under-provisioning of the EC2 instances, which can result in wasted resources or poor performance. Rightsizing also helps to take advantage of the different pricing models and features that AWS offers, such as On-Demand, Reserved, and Spot Instances, and Auto Scaling.

Explanation: Global reach is the benefit of AWS Cloud computing that provides lower latency between users and applications. Global reach means that AWS customers can deploy their applications and data in multiple regions around the world, and deliver them to users with high performance and availability. AWS has the largest global infrastructure of any cloud provider, with 25 geographic regions and 81 Availability Zones, as well as 216 Points of Presence in 84 cities across 42 countries. Customers can choose the optimal locations for their applications and data based on their business requirements, such as compliance, data sovereignty, and customer proximity. Agility, economies of scale, and pay-as-you-go pricing are other benefits of AWS Cloud computing, but they do not directly provide lower latency between users and applications. Agility means that AWS customers can quickly and easily provision and scale up or down AWS resources as needed, without upfront costs or long-term commitments. Economies of scale means that AWS customers can benefit from the lower costs and higher efficiency that AWS achieves by operating at a massive scale and passing the savings to the customers. Pay-as-you-go pricing means that AWS customers only pay for the AWS resources they use, without any upfront costs or long-term contracts.

Explanation: The AWS service that will meet the requirements of the company that is hosting a web application on Amazon EC2 instances and wants to implement custom conditions to filter and control inbound web traffic is AWS WAF. AWS WAF is a web application firewall that helps protect web applications from common web exploits that could affect availability, compromise security, or consume excessive resources. The company can use AWS WAF to create custom rules that block malicious requests that match certain patterns, such as SQL injection or cross-site scripting. AWS WAF can be applied to web applications that are behind an Application Load Balancer, Amazon CloudFront, or Amazon API Gateway. Amazon GuardDuty, Amazon Macie, and AWS Shield are not the best services to use for this purpose. Amazon GuardDuty is a threat detection service that monitors for malicious activity and unauthorized behavior across the AWS accounts and resources. Amazon Macie is a data security and data privacy service that uses machine learning and pattern matching to discover, classify, and protect sensitive data stored in Amazon S3. AWS Shield is a managed distributed denial of service (DDoS) protection service that safeguards web applications running on AWS. These services are more useful for detecting and preventing different types of threats and attacks, rather than filtering and controlling inbound web traffic based on custom conditions.

Explanation: The perspective of the AWS Cloud Adoption Framework (AWS CAF) that connects technology and business is governance. The governance perspective focuses on the alignment of the IT strategy and processes with the business strategy and goals, as well as the management of the IT budget, risk, and compliance. The governance perspective capabilities are portfolio management, business performance management, and IT governance. The governance perspective helps organizations ensure that their cloud adoption delivers the expected business value and outcomes, and that their cloud solutions are secure, reliable, and compliant. Operations, people, and security are other perspectives of the AWS CAF, but they do not directly connect technology and business. The operations perspective focuses on the management and monitoring of the cloud resources and applications, as well as the automation and optimization of the operational processes. The people perspective focuses on the development and empowerment of the human resources, as well as the transformation of the organizational culture and structure. The security perspective focuses on the protection of the information assets and systems in the cloud, as well as the implementation of the security policies and controls.

Explanation: Amazon Redshift Serverless is the AWS service that will meet the requirements of the company that wants to move its data warehouse application to the AWS Cloud and run and scale its analytics services without needing to provision and manage data warehouse clusters. Amazon Redshift Serverless is a new feature of Amazon Redshift, which is a fully managed data warehouse service that allows customers to run complex queries and analytics on large volumes of structured and semi-structured data. Amazon Redshift Serverless automatically scales the compute and storage resources based on the workload demand, and customers only pay for the resources they consume. Amazon Redshift Serverless also simplifies the management and maintenance of the data warehouse, as customers do not need to worry about choosing the right cluster size, resizing the cluster, or distributing the data across the nodes. Amazon Redshift provisioned data warehouse, Amazon Athena, and Amazon S3 are not the best services to meet the requirements of the company. Amazon Redshift provisioned data warehouse requires customers to choose the number and type of nodes for their cluster, and manually resize the cluster if their workload changes. Amazon Athena is a serverless query service that allows customers to analyze data stored in Amazon S3 using standard SQL, but it is not a data warehouse service that can store and organize the data. Amazon S3 is a scalable object storage service that can store any amount and type of data, but it is not a data warehouse service that can run complex queries and analytics on the data.

Explanation: Under the AWS shared responsibility model, AWS is responsible for ensuring the security of the internal network in the AWS data centers, as well as the physical security of the hardware and facilities that run AWS services. AWS customers are responsible for configuring the security group rules that determine which ports are open on an EC2 Linux instance, patching the guest operating system with the latest security patches on EC2, and turning on server-side encryption for S3 buckets.

Explanation: AWS Enterprise Support is the AWS Support plan that includes an AWS concierge whom the company can ask for assistance. According to the AWS Support Plans page, AWS Enterprise Support provides "a dedicated Technical Account Manager (TAM) who provides advocacy and guidance to help plan and build solutions using best practices, coordinate access to subject matter experts, and proactively keep your AWS environment operationally healthy."2 AWS Business Support, AWS Developer Support, and AWS Basic Support do not include a TAM or a concierge service.

Explanation: Operations is an option that is a perspective that includes foundational capabilities of the AWS Cloud Adoption Framework (AWS CAF). Operations is one of the six perspectives of the AWS CAF, along with business, people, governance, platform, and security. Operations focuses on the processes and procedures to support the ongoing management and maintenance of the cloud-based IT assets. It covers topics such as monitoring, backup and recovery, change management, incident management, and automation5. Sustainability is not a perspective of the AWS CAF, but a concept that refers to the ability of a system to operate in an environmentally friendly and socially responsible manner. Performance efficiency is not a perspective of the AWS CAF, but a pillar of the AWS Well-Architected Framework. It focuses on using the right resources and services for the workload, monitoring performance, and continuously improving the efficiency of the solution. Reliability is not a perspective of the AWS CAF, but a pillar of the AWS Well- Architected Framework. It focuses on the ability of a system to recover from infrastructure or service disruptions, dynamically acquire computing resources to meet demand, and mitigate disruptions such as misconfigurations or transient network issues.