AWS Cloud Practitioner Study Session Five

December 30, 2025

I am taking the AWS Cloud Practitioner Exam in approximately five days and want to ensure I am prepared. This series will serve as non-exhaustive note taking for the information that I am internalizing as I go.

Study materials:

Notes:

Cloud Formation - Helps model and set up AWS resources (Infra as Code).

Ways to interact with AWS Resources

Programmatic Access - AWS CLI, AWS SDKs, Good for automate routine tasks, Invoke APIs for one part of an application process
AWS Management Console - Web interface for quick access to services, Good for billing, services focused on graphical representation
Infrastructure as Code - Ex. Cloud Formation, Good for managing infrastructure with DevOps such as CI/CD pipelines, scaling resources such as EC2 to multi-Region applications in a consistent, repeatable way

Edge locations: Part of the AWS content delivery network (CDN), designed for caching content to improve delivery speed.

Primary Factors in Region Selection: (1) Compliance (does the Region meet the use case’s legal / regulatory requirements) (2) Proximity to customers to reduce latency (3) Feature availability (4) Pricing (varies by region)

VPCs: Logically isolated section of AWS Cloud to provision AWS resources in virtual network

Use Cases: Used to share public resources, used to organize resources, used to isolate resources and keep them private.
Subnet: Organizes resources publically or privately
Private Subnet: Commonly used to contain resources like a database storing customer or transactional information.
Public Subnet: Commonly used for resources like a customer-facing website.

VPN: Encrypts traffic between on-premise network and VPC. A Virtual Private Gateway is the VPN on the AWS side. Client VPN: From an individual device to private network. Site to Site VPN: Between two networks, not individual users.

AWS PrivateLink:

Use Case: Used for connecting clients in your VPC to resources (other VPCs, endpoints)
Benefit: Helps secure traffic and connect with simplified management rules

AWS Direct Connect

Use Case: Makes it possible to establish dedicated private connection between network and VPC in cloud. Good for latency-sensitive applications, large-scale data migration / transfer, hybrid cloud architectures.
Benefit: Reduces network costs, increases bandwidth

AWS Transit Gateway

Used to connect Amazon VPCs and on-prem networks through central hub.

Network Address Translation (Nat) Gateway

Can use a NAT gateway so that instances in a private subnet can connect to services outside VPC but external services can’t initiate a connection with those instances.

Amazon API Gateway

AWS service for creating, publishing, maintaining, monitoring, securing APIs at any scale.

Network ACL

Virtual firewall that controls inbound / outbound traffic at the subnet level.

Stateless Packet Filtering

Remembering nothing and check packets that cross the subnet border both inbound and outbound.
Network ACLs perform stateless packet filtering.

Security Groups

Component of VPC that checks packet permissions for an EC2 instance.
Virtual firewall that controls inbound / outbound traffic for specific AWS resources, like Amazon EC2.

Comparing Security Groups and Network ACLs

Feature	Security Group	Network ACLs
Scope	Instance level	Subnet level
State	Stateful	Stateless
Rule Types	Only allow rules	Allow and deny rules
Return traffic	Automatically allowed if inbound traffic allowed	Return traffic must be implicitly allowed
Uses	Fine-grained control of traffic for EC2 instances	Broad control of traffic in and out of subnets

AWS Global Accelerator

Networking service. Analogy: acts as express lanes on internet highway. Result: Faster and more reliable application network traffic.
Takes into account endpoint health, user location, and policies.
Use case examples: Global gaming company, financial services application

Amazon Route 53

Connects user requests to infrastructure running on AWS and elsewhere.
Manages DNS records (translates human readable into machine readable) for domain names through a single service.
Works with CloudFront

Amazon CloudFront

Content delivery network (CDN) service. Analogy: acts as a network of delivery trucks that quickly bring web content to users around the world.
Impact: Websites, videos, images, applications load much faster, no matter where customers are located. So look for media-rich, global, low-latency use cases.

Example Delivering content with low latency for a seamless experience across multiple Regions.

Users -> Access through custom domain sent to Route 53 DNS record -> Route 53 uses routing policy to determine region closest to user, directs to appropriate CloudFront edge location. -> Web content is fetched from the designated origin server in chosen Region.

I found digesting the material on this one more intensive than past modules. Probably one to return to.