DEV Community

Wakeup Flower
Wakeup Flower

Posted on

When use Aws Global Accelerator / CloudFront

#cloud #networking #architecture #aws

1️⃣ AWS Global Accelerator

Purpose: Improve availability and performance of TCP/UDP traffic for your global users.

  • Use case: You have applications hosted in multiple AWS regions (EC2, ALB, NLB) and you want:

    • Low-latency routing to the closest healthy region.
    • Automatic failover if a region or endpoint goes down.

  • Traffic type: Any TCP/UDP traffic, including non-HTTP protocols (gaming, IoT, APIs).

  • Mechanism:

    • Uses static IP addresses as entry points.
    • Routes traffic over the AWS global network instead of the public internet → faster & more reliable.

✅ Example:

  • Multi-region web application with ALB in us-east-1 and eu-west-1.
  • Users in Europe → routed to eu-west-1, users in US → routed to us-east-1.
  • If a region fails → traffic automatically goes to the other region.

2️⃣ Amazon CloudFront

Purpose: Distribute content to end users via a global edge network.

  • Use case: You want low-latency delivery of static or dynamic content (web pages, images, videos, API responses).
  • Traffic type: HTTP / HTTPS only.

  • Mechanism:

    • Caches content at edge locations close to users.
    • Can integrate with S3, ALB, API Gateway, or custom origins.
    • Provides DDoS protection via AWS Shield Standard.

✅ Example:

  • Website hosted in US.
  • Users in Asia → get content from nearest CloudFront edge instead of traveling all the way to US.
  • Dynamic API requests can also go through CloudFront with caching + origin failover.

3️⃣ Key Differences

Feature Global Accelerator CloudFront
Protocol TCP/UDP HTTP/HTTPS only
Focus Availability & routing across regions Content caching & delivery
Latency Optimized by AWS global network Optimized by edge caching
Failover Automatic to healthy endpoints Optional origin failover
Best for Multi-region apps, gaming, APIs Websites, videos, APIs, static assets

4️⃣ Rule of Thumb

  • Use Global Accelerator → You need fast, highly available routing for any type of traffic across regions.
  • Use CloudFront → You want content cached at edges for HTTP/HTTPS to improve user experience and reduce load on origin.

💡 Bonus: You can combine both.

  • CloudFront for caching content at edges.
  • Global Accelerator to route users to the closest regional origin if you have multiple regions.

1️⃣ Example Scenario

  • Video recommendation engine: Dynamic content generation (personalized).
  • EC2 Auto Scaling behind ALB: Scales within a single AWS Region.
  • Global users: Millions worldwide.
  • Challenge: Reduce latency for global users while keeping costs optimized.

2️⃣ Key Requirements

  1. Low latency for global users → users far from the Region experience slow response.
  2. Dynamic content (personalized) → can’t just cache everything; caching is limited.
  3. Scalability → must handle millions of users.
  4. Cost-optimized → can’t deploy full workloads in multiple regions if not necessary.

3️⃣ Candidate AWS Services

Option Analysis
Amazon CloudFront Great for caching static content or dynamic content via edge locations. Supports dynamic content acceleration (dynamic origin fetch). Can improve performance for dynamic APIs. Cost-effective, no need to deploy EC2 globally.
AWS Global Accelerator Routes traffic over the AWS global network to the closest healthy regional endpoint. Optimizes TCP/UDP routing. Useful for multi-region setups. May be overkill if you only have one region.
Deploy EC2/ALB in multiple regions True multi-region deployment reduces latency but increases cost (duplicate infrastructure + cross-region replication). Not cost-optimized.

4️⃣ Recommended Solution: CloudFront with dynamic content acceleration

  • Why?
  1. CloudFront can accelerate dynamic content by using edge locations globally → reduces latency for API calls.
  2. Users still hit the single backend region (EC2/ALB), so no need to deploy additional EC2 in other regions → cost-optimized.
  3. Works seamlessly with personalized recommendations because CloudFront supports cache-control headers and dynamic origin fetch.
  4. Optionally, you can add Lambda\@edge to do minor personalization or pre-processing at edge locations if needed.

✅ Architecture Flow 

User (Global)
   |
   v
CloudFront (edge location worldwide)
   |
   v
ALB in single region
   |
   v
EC2 Auto Scaling group (recommendation engine)
Enter fullscreen mode Exit fullscreen mode
  • Users worldwide → requests routed to nearest CloudFront edge → CloudFront forwards dynamic requests to ALB → EC2 generates personalized recommendations.
  • Static assets (images, thumbnails, CSS/JS) can be fully cached at CloudFront → reduces load on EC2.

5️⃣ Why not Global Accelerator?

  • GA is better when you have multiple regional endpoints and need fast failover + optimized routing.
  • In this case: single region → GA adds extra cost but won’t reduce latency as effectively as CloudFront for dynamic HTTP/HTTPS traffic.

✅ Answer: Use Amazon CloudFront in front of your ALB + EC2 backend.

  • Improves global performance
  • Scales automatically
  • Cost-efficient
  • Supports both static and dynamic content

Top comments (0)