AWS Basics - Cloud Computing Fundamentals

• What is Cloud Computing?
• Why Cloud Computing?
• Service Models
  • Infrastructure as a Service (IaaS)
  • Platform as a Service (PaaS)
  • Software as a Service (SaaS)
• Deployment Strategies
• Shared Responsibility Model
• AWS Service Categories
• AWS Global Infrastructure

What is Cloud Computing?

Cloud computing is a way to access and use IT resources over the internet with a pay-as-you-go pricing model. Instead of owning and maintaining physical servers, you can rent computing power, storage, and other services from cloud providers like AWS.

Why Cloud Computing?

• On-demand delivery: Get resources when you need them, instantly
• 24/7 availability: IT resources like network, storage, and compute are available around the clock
• Scalability: Meet changing customer needs by scaling up or down
• Cost efficiency: Pay-as-you-go pricing model - pay only for what you need and when you use it

Service Models

Cloud services provide different levels of control, flexibility, and management. Here are the three main service models:

Service Model	Description	Control Level	Examples
IaaS	Infrastructure as a Service	Highest	EC2, VPC, EBS
PaaS	Platform as a Service	Medium	Elastic Beanstalk, Lambda
SaaS	Software as a Service	Lowest	Office 365, Gmail

Infrastructure as a Service (IaaS)

• Provides access to database storage, networking features, virtual computers, and dedicated hardware
• Offers the highest level of flexibility and management over IT resources
• You manage the operating system, applications, and data
• AWS Examples: EC2, VPC, EBS, S3

Platform as a Service (PaaS)

• Removes the need for organizations to manage underlying infrastructure
• Focus on deployment and management of applications
• Developers can be more efficient without worrying about resource provisioning, software maintenance, patching, or capacity planning
• AWS Examples: Elastic Beanstalk, AWS Lambda, RDS

Software as a Service (SaaS)

• Complete software product that the service provider runs and manages
• You don't think about underlying infrastructure or service maintenance
• Focus only on how to use the particular software
• Examples: Office 365, Salesforce, Gmail

Deployment Strategies

Strategy	Description	Use Case
Cloud	100% cloud-based deployment	New applications, startups
Hybrid	Mix of cloud and on-premises	Gradual migration, compliance needs
On-Premises	Traditional data center	Strict compliance, legacy systems

Hybrid Approach

Many organizations start with a hybrid approach to gradually migrate to the cloud while maintaining critical on-premises systems.

Shared Responsibility Model

Important Concept

Each deployment method has a shared responsibility between you and AWS. You need to understand what you're responsible for and what AWS manages.

AWS Responsibilities (Security OF the Cloud):

• Physical security of data centers
• Hardware and software infrastructure
• Network controls and host operating system patching

Customer Responsibilities (Security IN the Cloud):

• Data encryption
• Network traffic protection
• Operating system updates
• Identity and access management

AWS Service Categories

AWS offers services across multiple categories:

• Compute: EC2, Lambda, ECS
• Storage: S3, EBS, EFS
• Databases: RDS, DynamoDB, Aurora
• Analytics: Redshift, EMR, Athena
• Networking & Content Delivery: VPC, CloudFront, Route 53
• Developer Tools: CodeCommit, CodeBuild, CodeDeploy
• Management & Governance: CloudWatch, CloudTrail, Config
• Machine Learning: SageMaker, Rekognition, Comprehend
• Security: IAM, KMS, GuardDuty

AWS Global Infrastructure

The AWS Global Infrastructure consists of three main components:

• Regions
• Availability Zones (AZs)
• Edge Locations