Amazon Web Services SAA-C03 - AWS Certified Solutions Architect - Associate (SAA-C03)

AWS Control Tower is a fully managed service that simplifies the setup and governance of a secure, compliant, multi-account AWS environment. It establishes a landing zone that is based on best-practices blueprints, and it enables governance using controls you can choose from a pre-packaged list. The landing zone is a well-architected, multi-account baseline that follows AWS best practices. Controls implement governance rules for security, compliance, and operations. AWS Security Hub is a service that provides a comprehensive view of your security posture across your AWS accounts. It aggregates, organizes, and prioritizes security alerts and findings from multiple AWS services, such as Amazon GuardDuty, Amazon Inspector, Amazon Macie, AWS Firewall Manager, and AWS IAM Access Analyzer, as well as from AWS Partner solutions. AWS Security Hub continuously monitors your environment using automatedcompliance checks based on the AWS best practices and industry standards, such as the AWS Foundational Security Best Practices (FSBP) standard. AWS Control Tower Account Factory is a feature that automates the provisioning of new AWS accounts that are preconfigured to meet your business, security, and compliance requirements. By deploying an AWS Control Tower environment in the Organizations management account, you can leverage the existing organization structure and policies, and enable AWS Security Hub and AWS Control Tower Account Factory in the environment. This way, you can audit all API calls and logins in any existing or new AWS account, monitor the compliance status of each account with the FSBP standard, and provision new accounts with ease and consistency. This solution meets the requirements with the least operational overhead, as you do not need to manage any infrastructure, perform any data migration, or submit any requests for changes.

AWS Lambda is a serverless compute service that allows you to run code without provisioning or managing servers. You can create Lambda functions using various languages, including Java, and specify the amount of memory and CPU allocated to your function. Lambda charges you only for the compute time you consume, which is calculated based on the number of requests and the duration of your code execution. You can use Amazon EventBridge to trigger your Lambda function on a schedule, such as every hour, using cron or rate expressions. This solution will optimize the costs to run the job, as you will not payfor any idle time or unused resources, unlike running the job on an EC2 instance. References: 1: AWS Lambda - FAQs2, General Information section2: Tutorial:Schedule AWS Lambda functions using EventBridge3, Introduction section3: Schedule expressions using rate or cron - AWS Lambda4, Introduction section.

This solution will meet the requirements of minimizing hosting service costs based on demand and providing the streaming content of a movie within 5 minutes of a user purchase. S3 Intelligent-Tiering is a storage class that automatically optimizes storage costs by moving data to the most cost-effective access tier when access patterns change. It is suitable for data with unknown, changing, or unpredictable access patterns, such as newer movies that may have higher demand1. S3 Glacier Flexible Retrieval is a storage class that provides low-cost storage for archive data that is retrieved asynchronously. It offers flexible data retrieval options fromminutes to hours, and free bulk retrievals in 5-12 hours. It is ideal for backup, disaster recovery, and offsite data storage needs2. By using expedited retrieval, the user can access the older movie video file in 1-5 minutes, which meets the requirement of 5 minutes3.

A write-through caching strategy adds or updates data in the cache whenever data is written to the database. This ensures that the data in the cache is always consistent with the data in the database. A write-through caching strategy also reduces the cache miss penalty, as data is always available in the cache when it is requested. However, a write-through caching strategy can increase the write latency, as data has to be written to both the cache and the database. A write-through caching strategy is suitable for applications that require high data consistency and low read latency.

A lazy loading caching strategy only loads data into the cache when it is requested, and updates the cache when there is a cache miss. This can result in stale data in the cache, as data is not updated in the cache when it is changed in the database. A lazy loading caching strategy is suitable for applications that can tolerate some data inconsistency and have a low cache miss rate.

An adding TTL caching strategy assigns a time-to-live (TTL) value to each data item in the cache, and removes the data from the cache when the TTL expires. This can help prevent stale data in the cache, as data is periodically refreshed from the database. However, an adding TTL caching strategy can also increase the cache miss rate, as data can be evicted from the cache before it is requested. An adding TTL caching strategy is suitable for applications that have a high cache hit rate and can tolerate some data inconsistency.

An AWS AppConfig caching strategy is not a valid option, as AWS AppConfig is a service that enables customers to quickly deploy validated configurations to applications of any size and scale. AWS AppConfig does not provide a caching layer for web applications.

This solution meets the following requirements:

It is private and secure, as it allows the EC2 instances to access the S3 bucket without using the public internet. A VPC endpoint is a gateway that enables you to create a private connection between your VPC and another AWS service, such as S3, within the same Region. A VPC endpoint for S3 provides secure and direct access to S3 buckets and objects using private IP addresses from your VPC. You can also use VPC endpoint policies and S3 bucket policies to control the access to the S3 resources based on the endpoint, the IAM user, the IAM role, or the source IP address.

It is simple and scalable, as it does not require any additional AWS services, gateways, or NAT devices. A VPC endpoint for S3 is a fully managed service that scales automatically with the network traffic. You can create a VPC endpoint for S3 with a few clicks in the VPC console or with a simple API call. You can also use the same VPC endpoint to access multiple S3 buckets in the same Region.