Global Infrastructure

AWS CLF-C02 — Route 53, CloudFront, Global Accelerator, Outposts, WaveLength, Local Zones

Why Go Global?

Decreased Latency — deploy applications closer to users worldwide for a faster experience
Disaster Recovery (DR) — if one region fails, you can failover to another region; increased availability
Attack Protection — distributed infrastructure is harder to attack
Data Compliance — some regulations require data to stay in specific geographic regions

AWS Global Infrastructure

Regions — physical locations with clusters of data centers (30+ regions)
Availability Zones (AZs) — one or more discrete data centers within a region (3-6 per region)
Edge Locations / Points of Presence — 450+ locations for content delivery (CloudFront)

Amazon Route 53

A managed Domain Name System (DNS) web service. Highly available, scalable, and authoritative DNS.

DNS Record Types

Record	Purpose	Example
A	Maps hostname to IPv4 address	`example.com → 12.34.56.78`
AAAA	Maps hostname to IPv6 address	`example.com → 2001:db8::1`
CNAME	Maps hostname to another hostname	`search.example.com → www.example.com`
Alias	Maps hostname to an AWS resource	`example.com → ELB DNS name`

Key Point:

Alias records are an AWS extension to DNS. They work like CNAME but can be used for the zone apex (root domain like example.com). CNAME cannot be used for the root domain. Alias records are free and support native health checks.

Route 53 Routing Policies

Policy	Description	Use Case
Simple	Route to a single resource. No health checks.	Single server, simple setup
Weighted	Distribute traffic by assigned weight percentages	A/B testing, gradual migration (e.g., 70/30 split)
Latency-based	Route to region with lowest latency for the user	Global apps needing best performance
Failover	Active-passive failover using health checks	Disaster recovery to a secondary site
Geolocation	Route based on user's geographic location	Localized content, restrict distribution by country
Geoproximity	Route based on geographic location with bias to shift traffic	Shift traffic between regions using bias values
Multi-value	Return multiple healthy resources (up to 8). Client-side load balancing.	Simple load balancing with health checks

Exam Tip:

Weighted = percentage split. Latency = fastest for user. Failover = DR. Geolocation = route by country/continent. Know the difference between Geolocation (user location) and Latency (network speed).

Amazon CloudFront

A global Content Delivery Network (CDN) that caches content at 450+ edge locations worldwide.

Key Features

Improves read performance by caching content at the edge
Built-in DDoS protection via AWS Shield
Integration with AWS WAF (Web Application Firewall)
Can expose HTTPS endpoints and can talk to internal HTTPS backends

CloudFront Origins

S3 Bucket — distribute files and cache at the edge. Enhanced security with Origin Access Control (OAC). Can also be used as an ingress (upload files to S3 through CloudFront).
Custom HTTP Origin — Application Load Balancer, EC2 instance, S3 static website, any HTTP backend

CloudFront vs S3 Cross-Region Replication

Feature	CloudFront	S3 Cross-Region Replication
Network	450+ edge locations globally	Specific regions you choose
Caching	Files cached for a TTL (time-to-live)	Near real-time replication
Content Type	Static content available everywhere	Dynamic content with low latency in specific regions
Setup	Automatic global distribution	Must be set up for each target region
Read/Write	Read-only cache	Read-only replicas (or read-write with different config)

Exam Tip:

CloudFront = static content cached globally, great for widely distributed users. S3 Cross-Region Replication = dynamic content that must be available at low latency in a few specific regions.

S3 Transfer Acceleration

Speed up uploads to S3 by transferring data to an edge location, which forwards it to the S3 bucket over the AWS private network.

Uses CloudFront's edge locations as entry points
Compatible with multi-part upload
Best for long-distance transfers (e.g., uploading from another continent)
File is uploaded to the nearest edge location → transferred over optimized AWS backbone

AWS Global Accelerator

Improve global application availability and performance using the AWS global network. Routes traffic through AWS edge locations to optimal endpoints.

How It Works

Provides 2 static Anycast IP addresses for your application
Traffic goes to the nearest edge location, then travels over the AWS private network (not the public internet)
Routes to the optimal endpoint (in any region)
Supports health checks — automatic failover in less than 1 minute
Works with Elastic IP, EC2, ALB, NLB (public or private)

Global Accelerator vs CloudFront

Feature	CloudFront	Global Accelerator
Content Type	Cacheable content (images, videos, static files)	Non-cacheable content (TCP/UDP traffic)
Mechanism	Caches at edge locations	Proxies packets at edge, no caching
Protocol	HTTP/HTTPS	TCP/UDP (wider range)
IP Addresses	Dynamic (DNS-based)	2 static Anycast IPs
Use Case	Static content delivery (CDN)	Gaming, IoT, VoIP, HTTP with static IPs

Exam Tip:

CloudFront = CDN for cacheable content (HTTP). Global Accelerator = improve performance for TCP/UDP, provides static IPs. If the question mentions "static IP" or "gaming/IoT," think Global Accelerator.

AWS Outposts

AWS-managed infrastructure delivered on-premises (in your own data center).

AWS installs physical servers ("Outposts Racks") in your data center
Run AWS services locally: EC2, EBS, S3, EKS, ECS, RDS, EMR
You are responsible for physical security of the Outpost
Use cases: data residency, low latency to on-premises systems, local data processing, migration
Extends a VPC to your on-premises location

Key Point:

Outposts = AWS services running in YOUR data center. "Hybrid cloud" with full AWS API experience on-premises. Think Outposts when the exam asks about "on-premises AWS" or "data residency requirements."

AWS WaveLength

Infrastructure deployments embedded within 5G network providers' data centers at the edge of telecom carriers' networks.

Ultra-low latency applications through 5G networks
Deploy AWS compute and storage at the 5G edge
Traffic never leaves the telecom provider's network
Use cases: smart cities, ML-assisted diagnostics, connected vehicles, interactive live video streams, AR/VR, real-time gaming

Exam Tip:

WaveLength = 5G edge computing. If the exam mentions "5G" or "telecom edge," the answer is WaveLength.

AWS Local Zones

Extend your VPC to additional locations closer to end users for latency-sensitive applications.

An extension of an AWS Region in a geographic location close to large population centers
Run latency-sensitive workloads closer to end users
Compatible with EC2, RDS, ECS, EBS, ElastiCache, Direct Connect
Example: AWS Region is N. Virginia (us-east-1), but Local Zone in Boston, Chicago, Dallas, etc.
Use cases: media & entertainment, real-time gaming, live streaming, AR/VR

Global vs Regional Summary

Concept	Description
Region	Cluster of data centers. Deploy regional services here.
Availability Zone	1+ data centers within a region. High availability via multi-AZ.
Edge Location	CDN cache point. CloudFront + Global Accelerator.
Outposts	AWS infrastructure in YOUR data center.
WaveLength	AWS at the 5G edge (telecom network).
Local Zones	Extend a Region closer to users in a metro area.