System Design (HLD)CDN Providers Comparison

CDN Providers Comparison

LevelAdvanced

Duration75 mins

TopicCDN Providers Comparison

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AWS CloudFront: Deep AWS Ecosystem Integration

The CDN Built for AWS

When Amazon Web Services launched CloudFront in 2008, it wasn't just adding a CDN to its portfolio—it was recognizing a fundamental truth about modern application architecture: content delivery cannot be separated from application infrastructure.

Today, AWS CloudFront is the most deeply integrated CDN in the cloud ecosystem. It's not the largest (Akamai), not the most developer-friendly (Cloudflare), and not the fastest purging (Fastly). But for organizations running on AWS—which represents an estimated 32% of all cloud infrastructure spending—CloudFront offers something competitors cannot match: seamless, native integration with the entire AWS stack.

This page explores CloudFront's architecture, its unique Lambda@Edge computing capabilities, integration patterns with AWS services, and when the ecosystem advantage outweighs standalone CDN considerations.

What You Will Learn

By the end of this page, you will understand CloudFront's architecture and edge locations, Lambda@Edge and CloudFront Functions computing models, deep integration patterns with S3, ALB, API Gateway, and other AWS services, security configurations with AWS Shield and WAF, and when CloudFront is the optimal choice despite pure CDN feature gaps.

CloudFront Architecture and Network

CloudFront operates a global network of edge locations and regional edge caches, designed to integrate seamlessly with AWS origins while supporting external origins.

Network Scale:

600+ Points of Presence (POPs) across 100+ cities in 50+ countries
13 Regional Edge Caches for improved cache hit ratios
Direct fiber connections to AWS regions for origin fetches
AWS Global Accelerator integration for enhanced anycast routing

CloudFront Request Flow:

┌──────────────────────────────────────────────────────────────────────────────┐
│                      CloudFront Request Processing Flow                       │
├──────────────────────────────────────────────────────────────────────────────┤
│                                                                               │
│  Client Request                                                               │
│       │                                                                       │
│       │ DNS Resolution: d123.cloudfront.net                                  │
│       ▼                                                                       │
│  ┌───────────────────────┐                                                    │
│  │   Route 53 / DNS      │ → Anycast to nearest edge location                │
│  └───────────┬───────────┘                                                    │
│              │                                                                │
│              ▼                                                                │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │                     Edge Location (POP)                           │       │
│  │  ┌─────────────────┐  ┌─────────────────┐  ┌───────────────────┐ │       │
│  │  │ SSL Termination │→ │ CloudFront Func │→ │   Cache Check     │ │       │
│  │  │                 │  │ (Viewer Request)│  │                   │ │       │
│  │  └─────────────────┘  └─────────────────┘  └─────────┬─────────┘ │       │
│  │                                                      │           │       │
│  │                            Cache Hit ←───────────────┘           │       │
│  │                                │                                 │       │
│  │                                ▼           Cache Miss            │       │
│  │                         ┌──────────────┐       │                 │       │
│  │                         │ Serve        │       │                 │       │
│  │                         │ Response     │       ▼                 │       │
│  │                         └──────────────┘ ┌───────────────────┐   │       │
│  │                                          │ Lambda@Edge       │   │       │
│  │                                          │ (Origin Request)  │   │       │
│  │                                          └─────────┬─────────┘   │       │
│  └──────────────────────────────────────────────────────────────────┘       │
│                                                       │                      │
│                                                       ▼                      │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │              Regional Edge Cache (if applicable)                  │       │
│  │              Aggregates requests across multiple POPs             │       │
│  └───────────────────────────────────┬───────────────────────────────┘       │
│                                      │                                       │
│                                      ▼                                       │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │                         Origin Server                             │       │
│  │    ┌─────────┐  ┌─────────┐  ┌─────────────┐  ┌───────────────┐  │       │
│  │    │ S3      │  │ ALB/NLB │  │ API Gateway │  │ Custom Origin │  │       │
│  │    │ Bucket  │  │         │  │             │  │ (Any HTTP)    │  │       │
│  │    └─────────┘  └─────────┘  └─────────────┘  └───────────────┘  │       │
│  └───────────────────────────────────────────────────────────────────┘       │
└──────────────────────────────────────────────────────────────────────────────┘

Key Architectural Components

•Edge Locations — The primary POPs where content is cached and served. These run CloudFront's caching layer, CloudFront Functions, and can trigger Lambda@Edge.
•Regional Edge Caches (RECs) — Middle-tier caches between edge locations and origins. Improve cache hit ratios by aggregating requests from multiple POPs before going to origin. Particularly valuable for less popular content.
•Origin Groups — Enable origin failover by defining primary and secondary origins. CloudFront automatically fails over based on HTTP status codes.
•AWS Backbone — Origin fetches from AWS services use Amazon's private fiber network, providing lower latency and higher reliability than public internet paths.

Regional Edge Caches vs. Origin Shield

CloudFront's Regional Edge Caches serve a similar purpose to Cloudflare's paid Argo Tiered Caching or Fastly's Shield. However, CloudFront also offers explicit Origin Shield as an additional layer—a dedicated regional cache that further reduces origin load. Use Origin Shield for origins with limited capacity or high origin-fetch costs.

Deep AWS Service Integration

CloudFront's defining advantage is seamless integration with virtually every AWS service. These integrations often reduce complexity and cost compared to using third-party CDNs with AWS infrastructure.

Amazon S3 Integration:

The most common CloudFront pattern is serving static content from S3:

CloudFront + S3 Integration

# CloudFormation template for CloudFront + S3 static site
AWSTemplateFormatVersion: '2010-09-09'
Description: CloudFront distribution with S3 origin
 
Resources:
  # S3 Bucket - Private, no public access needed
  ContentBucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: my-static-content-bucket
      PublicAccessBlockConfiguration:
        BlockPublicAcls: true
        BlockPublicPolicy: true
        IgnorePublicAcls: true
        RestrictPublicBuckets: true
 
  # Origin Access Control - Secure S3 access
  CloudFrontOAC:
    Type: AWS::CloudFront::OriginAccessControl
    Properties:
      OriginAccessControlConfig:
        Name: S3-OAC
        OriginAccessControlOriginType: s3
        SigningBehavior: always
        SigningProtocol: sigv4
 
  # CloudFront Distribution
  Distribution:
    Type: AWS::CloudFront::Distribution
    Properties:
      DistributionConfig:
        Origins:
          - Id: S3Origin
            DomainName: !GetAtt ContentBucket.RegionalDomainName
            S3OriginConfig:
              OriginAccessIdentity: ''
            OriginAccessControlId: !GetAtt CloudFrontOAC.Id
        
        DefaultCacheBehavior:
          TargetOriginId: S3Origin
          ViewerProtocolPolicy: redirect-to-https
          CachePolicyId: !Ref CachePolicy
          # Enable compression
          Compress: true
        
        # Custom error responses for SPA
        CustomErrorResponses:
          - ErrorCode: 404
            ResponseCode: 200
            ResponsePagePath: /index.html
          - ErrorCode: 403
            ResponseCode: 200
            ResponsePagePath: /index.html
        
        Enabled: true
        HttpVersion: http2and3
        DefaultRootObject: index.html
        
  # Cache Policy for optimal static content
  CachePolicy:
    Type: AWS::CloudFront::CachePolicy
    Properties:
      CachePolicyConfig:
        Name: StaticContentCachePolicy
        DefaultTTL: 86400   # 24 hours
        MaxTTL: 31536000    # 1 year
        MinTTL: 60
        ParametersInCacheKeyAndForwardedToOrigin:
          EnableAcceptEncodingGzip: true
          EnableAcceptEncodingBrotli: true
          CookiesConfig:
            CookieBehavior: none
          HeadersConfig:
            HeaderBehavior: none
          QueryStringsConfig:
            QueryStringBehavior: none

Key S3 Integration Benefits:

No public S3 bucket required: Origin Access Control (OAC) lets CloudFront access private S3 buckets using IAM
S3 Transfer Acceleration not needed: CloudFront uploads to edge, then uses AWS backbone to S3
Reduced S3 costs: Serving from cache reduces S3 request charges significantly
Native CORS handling: CloudFront can pass CORS headers without custom Lambda

Application Load Balancer (ALB) Integration:

For dynamic applications running on EC2, ECS, or EKS:

CloudFront + ALB Best Practices
Consideration	Recommendation	Rationale
Origin Protocol	HTTPS only	Encrypt traffic between CloudFront and ALB
ALB Security Groups	Allow only CloudFront IPs	Use AWS-managed prefix list (com.amazonaws.global.cloudfront.origin-facing)
Origin Shield	Enable for high-traffic APIs	Reduce ALB load by aggregating cache misses
Cache Policy	Use CachingDisabled for dynamic	Forward all headers/cookies for session-based apps
Connection Keepalive	Enable persistent connections	Reduce TLS handshake overhead to origin

API Gateway Integration:

CloudFront in front of API Gateway provides:

Caching for read-heavy APIs: Cache GET responses to reduce Lambda invocations
Custom domains: Use your domain instead of API Gateway's default
WAF integration: AWS WAF rules applied at CloudFront protect the API
Cost optimization: Cache hits bypass API Gateway charges entirely

Zero-Cost Data Transfer

Data transfer from AWS origins (S3, ALB, API Gateway) to CloudFront is free. You only pay for CloudFront to viewer transfer. This is a significant cost advantage over third-party CDNs, which would incur both origin egress and CDN ingress costs.

Edge Computing: Lambda@Edge

Lambda@Edge extends AWS Lambda to CloudFront's edge locations, enabling sophisticated request and response manipulation at the network edge.

Lambda@Edge Execution Points:

Lambda@Edge functions can execute at four points in the request lifecycle:

┌────────────────────────────────────────────────────────────────────────────────┐
│                    Lambda@Edge Execution Points                                 │
├────────────────────────────────────────────────────────────────────────────────┤
│                                                                                 │
│   Client                                                                        │
│     │                                                                           │
│     │ ①                                                                         │
│     ▼                                                                           │
│  ┌────────────────────────────────────────────────────────────────────────┐    │
│  │                    VIEWER REQUEST                                       │    │
│  │  • Executes for every request                                          │    │
│  │  • Before cache check                                                  │    │
│  │  • Use cases: Auth, geo-redirect, URL rewrite                         │    │
│  │  • Limits: 5s timeout, 128MB memory, 1MB body                         │    │
│  └───────────────────────────────────┬────────────────────────────────────┘    │
│                                      │                                          │
│                                      ▼                                          │
│                            ┌─────────────────────┐                              │
│                            │    Cache Check      │                              │
│                            └─────────┬───────────┘                              │
│                                      │                                          │
│                     Cache Hit ◄──────┴──────► Cache Miss                        │
│                         │                         │                             │
│                         │                    ② │                             │
│                         │                         ▼                             │
│                         │    ┌────────────────────────────────────────────────┐│
│                         │    │                ORIGIN REQUEST                  ││
│                         │    │  • Executes only on cache miss                ││
│                         │    │  • Before origin fetch                        ││
│                         │    │  • Use cases: Origin selection, header manip  ││
│                         │    │  • Limits: 30s timeout, 128MB memory          ││
│                         │    └───────────────────────────────────────────────┘│
│                         │                         │                             │
│                         │                         ▼                             │
│                         │                    ┌─────────┐                        │
│                         │                    │ Origin  │                        │
│                         │                    └────┬────┘                        │
│                         │                         │                             │
│                         │                    ③ │                             │
│                         │                         ▼                             │
│                         │    ┌────────────────────────────────────────────────┐│
│                         │    │               ORIGIN RESPONSE                  ││
│                         │    │  • Executes after origin returns              ││
│                         │    │  • Before caching                             ││
│                         │    │  • Use cases: Response modification, headers  ││
│                         │    │  • Limits: 30s timeout, 128MB memory          ││
│                         │    └───────────────────────────────────────────────┘│
│                         │                         │                             │
│                         └────────────┬────────────┘                             │
│                                      ▼                                          │
│                                 ④                                            │
│  ┌────────────────────────────────────────────────────────────────────────┐    │
│  │                    VIEWER RESPONSE                                      │    │
│  │  • Executes for every response                                         │    │
│  │  • Before sending to client                                           │    │
│  │  • Use cases: Security headers, compression, CORS                     │    │
│  │  • Limits: 5s timeout, 128MB memory                                   │    │
│  └───────────────────────────────────┬────────────────────────────────────┘    │
│                                      │                                          │
│                                      ▼                                          │
│   Client                                                                        │
└────────────────────────────────────────────────────────────────────────────────┘

Lambda@Edge Examples

/**
 * Lambda@Edge: Viewer Request - JWT Authentication
 * Validate JWT tokens before requests reach origin
 */
const jwt = require('jsonwebtoken');
 
// Note: Must bundle secrets - cannot use environment variables
const JWT_SECRET = 'your-secret-key'; // In practice, use SSM or hardcoded during build
 
exports.handler = async (event) => {
    const request = event.Records[0].cf.request;
    const headers = request.headers;
    
    // Extract token from Authorization header
    const authHeader = headers['authorization'];
    if (!authHeader || !authHeader[0]) {
        return {
            status: '401',
            statusDescription: 'Unauthorized',
            headers: {
                'content-type': [{ key: 'Content-Type', value: 'application/json' }],
            },
            body: JSON.stringify({ error: 'Missing authorization header' }),
        };
    }
    
    const token = authHeader[0].value.replace('Bearer ', '');
    
    try {
        const decoded = jwt.verify(token, JWT_SECRET);
        
        // Add user info to headers for origin
        request.headers['x-user-id'] = [{ key: 'X-User-Id', value: decoded.sub }];
        request.headers['x-user-role'] = [{ key: 'X-User-Role', value: decoded.role }];
        
        return request;
        
    } catch (error) {
        return {
            status: '401',
            statusDescription: 'Unauthorized',
            headers: {
                'content-type': [{ key: 'Content-Type', value: 'application/json' }],
            },
            body: JSON.stringify({ error: 'Invalid token' }),
        };
    }
};

Lambda@Edge Limitations

Lambda@Edge functions must be deployed in us-east-1 and are replicated globally. They cannot access VPC resources, have limited memory (128MB), and cannot use environment variables. Cold starts are slower than Cloudflare Workers (100-200ms vs <5ms). Consider CloudFront Functions for simpler use cases.

CloudFront Functions: Lightweight Edge Computing

CloudFront Functions provide a lighter-weight alternative to Lambda@Edge for simple request/response manipulations, with significantly better performance characteristics.

CloudFront Functions vs Lambda@Edge:

Comparison: CloudFront Functions vs Lambda@Edge
Characteristic	CloudFront Functions	Lambda@Edge
Execution Points	Viewer request/response only	All four points
Runtime	JavaScript (ECMAScript 5.1)	Node.js or Python
Execution Time Limit	1 ms	5-30 seconds
Memory	2 MB	128-10,240 MB
Package Size	10 KB	1-50 MB
Network Access	None	Full internet access
Cold Start	Sub-millisecond	100-200+ ms
Price	$0.10/million invocations	$0.60/million + duration
Scale	10M+ requests/second	10K requests/second per region

CloudFront Functions Examples

/**
 * CloudFront Function: Viewer Request - URL Rewriting
 * Rewrite clean URLs to actual file paths
 */
function handler(event) {
    var request = event.request;
    var uri = request.uri;
    
    // Handle SPA routing - serve index.html for paths without extensions
    if (!uri.includes('.')) {
        // Check if path ends with / or has no extension
        if (uri.endsWith('/')) {
            request.uri = uri + 'index.html';
        } else if (!uri.split('/').pop().includes('.')) {
            request.uri = '/index.html';
        }
    }
    
    // Add file extension for API versioning
    // /api/v2/users -> /api/v2/users.json
    if (uri.startsWith('/api/') && !uri.includes('.')) {
        request.uri = uri + '.json';
    }
    
    return request;
}

When to Use Which

Use CloudFront Functions for: URL rewrites, header manipulation, simple redirects, cache key normalization. Use Lambda@Edge for: authentication with external validation, complex routing logic, response body transformation, anything requiring network calls or more than 1ms execution time.

Security: AWS WAF and Shield Integration

CloudFront's security is deeply integrated with AWS's security services, providing layered protection from network to application level.

AWS Shield Integration:

All CloudFront distributions automatically receive AWS Shield Standard protection—free, always-on DDoS defense:

Protection against SYN/UDP floods, reflection attacks
Network-level attack mitigation
No configuration required

AWS Shield Advanced (paid, starting ~$3,000/month) adds:

Application-layer (L7) DDoS protection
24/7 access to AWS DDoS Response Team (DRT)
Cost protection—credits for scaling costs during attacks
Real-time metrics and reporting
Integration with AWS WAF managed rules

AWS WAF Integration:

AWS WAF provides web application firewall capabilities directly at the CloudFront edge:

AWS WAF Configuration

Terraform WAF

# AWS WAF Web ACL for CloudFront
resource "aws_wafv2_web_acl" "cloudfront_waf" {
  name        = "cloudfront-protection"
  description = "WAF rules for CloudFront distribution"
  scope       = "CLOUDFRONT"  # Must be CLOUDFRONT for CF distributions
  
  default_action {
    allow {}
  }
  
  # AWS Managed Rules - Core Rule Set
  rule {
    name     = "AWSManagedRulesCommonRuleSet"
    priority = 1
    
    override_action {
      none {}  # Use rule actions as-is
    }
    
    statement {
      managed_rule_group_statement {
        name        = "AWSManagedRulesCommonRuleSet"
        vendor_name = "AWS"
        
        # Exclude rules that cause false positives
        excluded_rule {
          name = "SizeRestrictions_BODY"
        }
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "CommonRuleSetMetric"
    }
  }
  
  # AWS Managed Rules - Known Bad Inputs
  rule {
    name     = "AWSManagedRulesKnownBadInputsRuleSet"
    priority = 2
    
    override_action {
      none {}
    }
    
    statement {
      managed_rule_group_statement {
        name        = "AWSManagedRulesKnownBadInputsRuleSet"
        vendor_name = "AWS"
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "BadInputsMetric"
    }
  }
  
  # Rate limiting rule
  rule {
    name     = "RateLimitRule"
    priority = 3
    
    action {
      block {}
    }
    
    statement {
      rate_based_statement {
        limit              = 2000  # requests per 5 minutes
        aggregate_key_type = "IP"
        
        scope_down_statement {
          # Only rate limit login endpoint
          byte_match_statement {
            search_string = "/api/auth/login"
            field_to_match {
              uri_path {}
            }
            positional_constraint = "STARTS_WITH"
            text_transformation {
              priority = 0
              type     = "LOWERCASE"
            }
          }
        }
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "RateLimitMetric"
    }
  }
  
  # Geo-blocking rule
  rule {
    name     = "GeoBlockRule"
    priority = 4
    
    action {
      block {}
    }
    
    statement {
      geo_match_statement {
        country_codes = ["RU", "CN", "KP"]  # Block specific countries
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "GeoBlockMetric"
    }
  }
  
  visibility_config {
    cloudwatch_metrics_enabled = true
    metric_name                = "CloudFrontWAF"
    sampled_requests_enabled   = true
  }
}
 
# Associate WAF with CloudFront distribution
resource "aws_cloudfront_distribution" "cdn" {
  # ... other config ...
  
  web_acl_id = aws_wafv2_web_acl.cloudfront_waf.arn
}

Available AWS Managed Rule Groups

•Core Rule Set (CRS) — General web application protection, OWASP Top 10
•SQL Database — Protection against SQL injection attacks
•Known Bad Inputs — Blocks requests with known malicious patterns
•Linux/POSIX OS — Protects against Linux-specific exploits
•Windows OS — Protects against Windows-specific exploits
•PHP Application — PHP-specific vulnerability protection
•WordPress Application — WordPress-specific protection
•Amazon IP Reputation — Blocks requests from known malicious IPs
•Bot Control — Managed bot detection and mitigation (additional cost)

WAF Pricing

AWS WAF charges $5/month per web ACL + $1/month per rule + $0.60 per million requests. Managed rule groups add $1-10/month per group. For high-traffic sites, request charges dominate. Bot Control adds $10/month + $1/million requests. Always enable sampled request logging to CloudWatch for debugging.

Advanced Caching Configuration

CloudFront's caching behavior is highly configurable through cache policies and origin request policies, enabling fine-grained control over what gets cached and what gets forwarded to origin.

Cache Policies:

Cache policies determine what's included in the cache key and TTL settings:

AWS Managed Cache Policies
Policy Name	Use Case	Key Characteristics
CachingOptimized	Static content	Long TTLs, no headers/cookies/query strings in key
CachingOptimizedForUncompressedObjects	Pre-compressed content	Like above, but doesn't normalize Accept-Encoding
CachingDisabled	Dynamic content	No caching, all requests to origin
Elemental-MediaPackage	Video streaming	Optimized for HLS/DASH manifest and segment caching
Amplify	Amplify Hosting	Configured for Amplify's caching patterns

Origin Request Policies:

Separate from cache policies, origin request policies control what CloudFront forwards to your origin when it needs to fetch content:

Custom Cache and Origin Request Policies

Terraform

# Custom cache policy for API responses
resource "aws_cloudfront_cache_policy" "api_cache" {
  name        = "API-Caching-Policy"
  comment     = "Cache API responses based on auth and accept headers"
  
  default_ttl = 300    # 5 minutes default
  max_ttl     = 3600   # 1 hour max
  min_ttl     = 0      # Respect Cache-Control: no-cache
  
  parameters_in_cache_key_and_forwarded_to_origin {
    # Include compression headers in cache key
    enable_accept_encoding_brotli = true
    enable_accept_encoding_gzip   = true
    
    # Include specific headers in cache key
    headers_config {
      header_behavior = "whitelist"
      headers {
        items = [
          "Authorization",        # Different cache per user
          "Accept-Language",      # Language-specific responses
          "CloudFront-Viewer-Country"  # Country-specific content
        ]
      }
    }
    
    # Include cookies in cache key
    cookies_config {
      cookie_behavior = "whitelist"
      cookies {
        items = ["session_id", "user_preferences"]
      }
    }
    
    # Include query strings in cache key
    query_strings_config {
      query_string_behavior = "whitelist"
      query_strings {
        items = ["page", "limit", "sort", "filter"]
      }
    }
  }
}
 
# Origin request policy - forward additional headers
resource "aws_cloudfront_origin_request_policy" "api_origin" {
  name    = "API-Origin-Policy"
  comment = "Forward necessary headers to API origin"
  
  headers_config {
    header_behavior = "whitelist"
    headers {
      items = [
        "Authorization",
        "Origin",
        "Access-Control-Request-Method",
        "Access-Control-Request-Headers",
        "X-Request-ID"
      ]
    }
  }
  
  cookies_config {
    cookie_behavior = "all"  # Forward all cookies to origin
  }
  
  query_strings_config {
    query_string_behavior = "all"  # Forward all query strings
  }
}
 
# Apply policies to cache behavior
resource "aws_cloudfront_distribution" "api" {
  # ... origin config ...
  
  default_cache_behavior {
    target_origin_id       = "api-origin"
    viewer_protocol_policy = "https-only"
    
    allowed_methods = ["DELETE", "GET", "HEAD", "OPTIONS", "PATCH", "POST", "PUT"]
    cached_methods  = ["GET", "HEAD"]
    
    cache_policy_id          = aws_cloudfront_cache_policy.api_cache.id
    origin_request_policy_id = aws_cloudfront_origin_request_policy.api_origin.id
    
    compress = true
  }
}

Cache Key Optimization

The cache key determines cache hit ratio. Include too little (e.g., ignore Authorization header) and you'll serve cached private data to wrong users. Include too much (e.g., all headers) and every request becomes a cache miss. Start with managed policies and customize only when needed.

CloudFront Pricing Structure

CloudFront uses consumption-based pricing with regional variation. Understanding the cost structure is essential for budgeting and optimization.

Pricing Components:

CloudFront Pricing (US/Europe Region)
Component	Price Range	Notes
Data Transfer Out (first 10TB)	$0.085/GB	Decreases with volume
Data Transfer Out (10-50TB)	$0.080/GB	Volume tier pricing
Data Transfer Out (50-150TB)	$0.060/GB	Volume tier pricing
HTTP/HTTPS Requests	$0.0075-0.01/10K	Varies by protocol and region
Origin Shield Requests	$0.0090/10K	Additional for cache aggregation
Lambda@Edge Invocations	$0.60/million	Plus duration-based compute
CloudFront Functions	$0.10/million	Significantly cheaper than L@E
Field-Level Encryption	$0.02/10K requests	For encrypting specific fields

Cost Optimization Strategies:

Reducing CloudFront Costs

•Maximize cache hit ratio — Every cache hit avoids origin transfer and origin request processing. Use cache policies wisely.
•Enable compression — Brotli/Gzip compression reduces data transfer by 70-90% for text content. CloudFront compresses for free.
•Use CloudFront Functions over Lambda@Edge — 6x cheaper per invocation for simple transformations.
•Consider Price Class — CloudFront offers reduced price classes that limit edge locations to cheaper regions.
•Use AWS origins — Data transfer from AWS services to CloudFront is free. Only edge-to-viewer transfer costs.
•Committed use discounts — CloudFront Security Savings Bundle offers 30% savings for 1-year commitment.

Free Tier

CloudFront's free tier includes 1TB data transfer out and 10 million HTTP/HTTPS requests per month for the first 12 months. This covers most startup needs during early development and testing phases.

When to Choose CloudFront

CloudFront's value proposition centers on AWS integration. Use this framework to evaluate fit:

CloudFront Is Ideal When

•AWS-centric infrastructure — Origins in S3, ALB, API Gateway benefit from free transfer and native integration
•Unified AWS billing — Single bill, consolidated reporting, reserved capacity discounts
•AWS IAM integration required — Native IAM policies, cross-account access patterns
•AWS WAF/Shield needed — Deep integration with AWS security services
•Using AWS Amplify/CDK — First-class infrastructure-as-code support
•Private origins via VPC — CloudFront + VPC origins access private resources
•S3 Object Lambda — Transform objects on-the-fly during delivery

Consider Alternatives When

•Multi-cloud architecture — Cloudflare/Fastly work equally well with any origin
•Real-time purge required — CloudFront invalidation is slower than Fastly
•Developer experience prioritized — Cloudflare Workers has better DX
•Security-first requirement — Cloudflare's included DDoS/security is more comprehensive
•Unmetered bandwidth needed — Cloudflare's flat pricing may be cheaper
•Edge data storage — Cloudflare KV/R2 is more mature than Lambda@Edge storage
•Non-AWS origins — Egress from other clouds to CloudFront incurs costs

Page Complete

You now understand AWS CloudFront's architecture, deep AWS integration advantages, edge computing capabilities with Lambda@Edge and CloudFront Functions, security integration, and when the AWS ecosystem value outweighs standalone CDN features. Next, we'll explore Fastly's real-time purge capabilities and developer-centric approach.

3 / 5

Loading learning content...

System Design (HLD)CDN Providers Comparison

CDN Providers Comparison

LevelAdvanced

Duration75 mins

TopicCDN Providers Comparison

3 / 5

AWS CloudFront: Deep AWS Ecosystem Integration

The CDN Built for AWS

What You Will Learn

CloudFront Architecture and Network

CloudFront operates a global network of edge locations and regional edge caches, designed to integrate seamlessly with AWS origins while supporting external origins.

Network Scale:

600+ Points of Presence (POPs) across 100+ cities in 50+ countries
13 Regional Edge Caches for improved cache hit ratios
Direct fiber connections to AWS regions for origin fetches
AWS Global Accelerator integration for enhanced anycast routing

CloudFront Request Flow:

┌──────────────────────────────────────────────────────────────────────────────┐
│                      CloudFront Request Processing Flow                       │
├──────────────────────────────────────────────────────────────────────────────┤
│                                                                               │
│  Client Request                                                               │
│       │                                                                       │
│       │ DNS Resolution: d123.cloudfront.net                                  │
│       ▼                                                                       │
│  ┌───────────────────────┐                                                    │
│  │   Route 53 / DNS      │ → Anycast to nearest edge location                │
│  └───────────┬───────────┘                                                    │
│              │                                                                │
│              ▼                                                                │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │                     Edge Location (POP)                           │       │
│  │  ┌─────────────────┐  ┌─────────────────┐  ┌───────────────────┐ │       │
│  │  │ SSL Termination │→ │ CloudFront Func │→ │   Cache Check     │ │       │
│  │  │                 │  │ (Viewer Request)│  │                   │ │       │
│  │  └─────────────────┘  └─────────────────┘  └─────────┬─────────┘ │       │
│  │                                                      │           │       │
│  │                            Cache Hit ←───────────────┘           │       │
│  │                                │                                 │       │
│  │                                ▼           Cache Miss            │       │
│  │                         ┌──────────────┐       │                 │       │
│  │                         │ Serve        │       │                 │       │
│  │                         │ Response     │       ▼                 │       │
│  │                         └──────────────┘ ┌───────────────────┐   │       │
│  │                                          │ Lambda@Edge       │   │       │
│  │                                          │ (Origin Request)  │   │       │
│  │                                          └─────────┬─────────┘   │       │
│  └──────────────────────────────────────────────────────────────────┘       │
│                                                       │                      │
│                                                       ▼                      │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │              Regional Edge Cache (if applicable)                  │       │
│  │              Aggregates requests across multiple POPs             │       │
│  └───────────────────────────────────┬───────────────────────────────┘       │
│                                      │                                       │
│                                      ▼                                       │
│  ┌───────────────────────────────────────────────────────────────────┐       │
│  │                         Origin Server                             │       │
│  │    ┌─────────┐  ┌─────────┐  ┌─────────────┐  ┌───────────────┐  │       │
│  │    │ S3      │  │ ALB/NLB │  │ API Gateway │  │ Custom Origin │  │       │
│  │    │ Bucket  │  │         │  │             │  │ (Any HTTP)    │  │       │
│  │    └─────────┘  └─────────┘  └─────────────┘  └───────────────┘  │       │
│  └───────────────────────────────────────────────────────────────────┘       │
└──────────────────────────────────────────────────────────────────────────────┘

Key Architectural Components

•Edge Locations — The primary POPs where content is cached and served. These run CloudFront's caching layer, CloudFront Functions, and can trigger Lambda@Edge.
•Regional Edge Caches (RECs) — Middle-tier caches between edge locations and origins. Improve cache hit ratios by aggregating requests from multiple POPs before going to origin. Particularly valuable for less popular content.
•Origin Groups — Enable origin failover by defining primary and secondary origins. CloudFront automatically fails over based on HTTP status codes.
•AWS Backbone — Origin fetches from AWS services use Amazon's private fiber network, providing lower latency and higher reliability than public internet paths.

Regional Edge Caches vs. Origin Shield

Deep AWS Service Integration

Amazon S3 Integration:

The most common CloudFront pattern is serving static content from S3:

CloudFront + S3 Integration

# CloudFormation template for CloudFront + S3 static site
AWSTemplateFormatVersion: '2010-09-09'
Description: CloudFront distribution with S3 origin
 
Resources:
  # S3 Bucket - Private, no public access needed
  ContentBucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: my-static-content-bucket
      PublicAccessBlockConfiguration:
        BlockPublicAcls: true
        BlockPublicPolicy: true
        IgnorePublicAcls: true
        RestrictPublicBuckets: true
 
  # Origin Access Control - Secure S3 access
  CloudFrontOAC:
    Type: AWS::CloudFront::OriginAccessControl
    Properties:
      OriginAccessControlConfig:
        Name: S3-OAC
        OriginAccessControlOriginType: s3
        SigningBehavior: always
        SigningProtocol: sigv4
 
  # CloudFront Distribution
  Distribution:
    Type: AWS::CloudFront::Distribution
    Properties:
      DistributionConfig:
        Origins:
          - Id: S3Origin
            DomainName: !GetAtt ContentBucket.RegionalDomainName
            S3OriginConfig:
              OriginAccessIdentity: ''
            OriginAccessControlId: !GetAtt CloudFrontOAC.Id
        
        DefaultCacheBehavior:
          TargetOriginId: S3Origin
          ViewerProtocolPolicy: redirect-to-https
          CachePolicyId: !Ref CachePolicy
          # Enable compression
          Compress: true
        
        # Custom error responses for SPA
        CustomErrorResponses:
          - ErrorCode: 404
            ResponseCode: 200
            ResponsePagePath: /index.html
          - ErrorCode: 403
            ResponseCode: 200
            ResponsePagePath: /index.html
        
        Enabled: true
        HttpVersion: http2and3
        DefaultRootObject: index.html
        
  # Cache Policy for optimal static content
  CachePolicy:
    Type: AWS::CloudFront::CachePolicy
    Properties:
      CachePolicyConfig:
        Name: StaticContentCachePolicy
        DefaultTTL: 86400   # 24 hours
        MaxTTL: 31536000    # 1 year
        MinTTL: 60
        ParametersInCacheKeyAndForwardedToOrigin:
          EnableAcceptEncodingGzip: true
          EnableAcceptEncodingBrotli: true
          CookiesConfig:
            CookieBehavior: none
          HeadersConfig:
            HeaderBehavior: none
          QueryStringsConfig:
            QueryStringBehavior: none

Key S3 Integration Benefits:

No public S3 bucket required: Origin Access Control (OAC) lets CloudFront access private S3 buckets using IAM
S3 Transfer Acceleration not needed: CloudFront uploads to edge, then uses AWS backbone to S3
Reduced S3 costs: Serving from cache reduces S3 request charges significantly
Native CORS handling: CloudFront can pass CORS headers without custom Lambda

Application Load Balancer (ALB) Integration:

For dynamic applications running on EC2, ECS, or EKS:

CloudFront + ALB Best Practices
Consideration	Recommendation	Rationale
Origin Protocol	HTTPS only	Encrypt traffic between CloudFront and ALB
ALB Security Groups	Allow only CloudFront IPs	Use AWS-managed prefix list (com.amazonaws.global.cloudfront.origin-facing)
Origin Shield	Enable for high-traffic APIs	Reduce ALB load by aggregating cache misses
Cache Policy	Use CachingDisabled for dynamic	Forward all headers/cookies for session-based apps
Connection Keepalive	Enable persistent connections	Reduce TLS handshake overhead to origin

API Gateway Integration:

CloudFront in front of API Gateway provides:

Caching for read-heavy APIs: Cache GET responses to reduce Lambda invocations
Custom domains: Use your domain instead of API Gateway's default
WAF integration: AWS WAF rules applied at CloudFront protect the API
Cost optimization: Cache hits bypass API Gateway charges entirely

Zero-Cost Data Transfer

Edge Computing: Lambda@Edge

Lambda@Edge extends AWS Lambda to CloudFront's edge locations, enabling sophisticated request and response manipulation at the network edge.

Lambda@Edge Execution Points:

Lambda@Edge functions can execute at four points in the request lifecycle:

┌────────────────────────────────────────────────────────────────────────────────┐
│                    Lambda@Edge Execution Points                                 │
├────────────────────────────────────────────────────────────────────────────────┤
│                                                                                 │
│   Client                                                                        │
│     │                                                                           │
│     │ ①                                                                         │
│     ▼                                                                           │
│  ┌────────────────────────────────────────────────────────────────────────┐    │
│  │                    VIEWER REQUEST                                       │    │
│  │  • Executes for every request                                          │    │
│  │  • Before cache check                                                  │    │
│  │  • Use cases: Auth, geo-redirect, URL rewrite                         │    │
│  │  • Limits: 5s timeout, 128MB memory, 1MB body                         │    │
│  └───────────────────────────────────┬────────────────────────────────────┘    │
│                                      │                                          │
│                                      ▼                                          │
│                            ┌─────────────────────┐                              │
│                            │    Cache Check      │                              │
│                            └─────────┬───────────┘                              │
│                                      │                                          │
│                     Cache Hit ◄──────┴──────► Cache Miss                        │
│                         │                         │                             │
│                         │                    ② │                             │
│                         │                         ▼                             │
│                         │    ┌────────────────────────────────────────────────┐│
│                         │    │                ORIGIN REQUEST                  ││
│                         │    │  • Executes only on cache miss                ││
│                         │    │  • Before origin fetch                        ││
│                         │    │  • Use cases: Origin selection, header manip  ││
│                         │    │  • Limits: 30s timeout, 128MB memory          ││
│                         │    └───────────────────────────────────────────────┘│
│                         │                         │                             │
│                         │                         ▼                             │
│                         │                    ┌─────────┐                        │
│                         │                    │ Origin  │                        │
│                         │                    └────┬────┘                        │
│                         │                         │                             │
│                         │                    ③ │                             │
│                         │                         ▼                             │
│                         │    ┌────────────────────────────────────────────────┐│
│                         │    │               ORIGIN RESPONSE                  ││
│                         │    │  • Executes after origin returns              ││
│                         │    │  • Before caching                             ││
│                         │    │  • Use cases: Response modification, headers  ││
│                         │    │  • Limits: 30s timeout, 128MB memory          ││
│                         │    └───────────────────────────────────────────────┘│
│                         │                         │                             │
│                         └────────────┬────────────┘                             │
│                                      ▼                                          │
│                                 ④                                            │
│  ┌────────────────────────────────────────────────────────────────────────┐    │
│  │                    VIEWER RESPONSE                                      │    │
│  │  • Executes for every response                                         │    │
│  │  • Before sending to client                                           │    │
│  │  • Use cases: Security headers, compression, CORS                     │    │
│  │  • Limits: 5s timeout, 128MB memory                                   │    │
│  └───────────────────────────────────┬────────────────────────────────────┘    │
│                                      │                                          │
│                                      ▼                                          │
│   Client                                                                        │
└────────────────────────────────────────────────────────────────────────────────┘

Lambda@Edge Examples

/**
 * Lambda@Edge: Viewer Request - JWT Authentication
 * Validate JWT tokens before requests reach origin
 */
const jwt = require('jsonwebtoken');
 
// Note: Must bundle secrets - cannot use environment variables
const JWT_SECRET = 'your-secret-key'; // In practice, use SSM or hardcoded during build
 
exports.handler = async (event) => {
    const request = event.Records[0].cf.request;
    const headers = request.headers;
    
    // Extract token from Authorization header
    const authHeader = headers['authorization'];
    if (!authHeader || !authHeader[0]) {
        return {
            status: '401',
            statusDescription: 'Unauthorized',
            headers: {
                'content-type': [{ key: 'Content-Type', value: 'application/json' }],
            },
            body: JSON.stringify({ error: 'Missing authorization header' }),
        };
    }
    
    const token = authHeader[0].value.replace('Bearer ', '');
    
    try {
        const decoded = jwt.verify(token, JWT_SECRET);
        
        // Add user info to headers for origin
        request.headers['x-user-id'] = [{ key: 'X-User-Id', value: decoded.sub }];
        request.headers['x-user-role'] = [{ key: 'X-User-Role', value: decoded.role }];
        
        return request;
        
    } catch (error) {
        return {
            status: '401',
            statusDescription: 'Unauthorized',
            headers: {
                'content-type': [{ key: 'Content-Type', value: 'application/json' }],
            },
            body: JSON.stringify({ error: 'Invalid token' }),
        };
    }
};

Lambda@Edge Limitations

CloudFront Functions: Lightweight Edge Computing

CloudFront Functions provide a lighter-weight alternative to Lambda@Edge for simple request/response manipulations, with significantly better performance characteristics.

CloudFront Functions vs Lambda@Edge:

Comparison: CloudFront Functions vs Lambda@Edge
Characteristic	CloudFront Functions	Lambda@Edge
Execution Points	Viewer request/response only	All four points
Runtime	JavaScript (ECMAScript 5.1)	Node.js or Python
Execution Time Limit	1 ms	5-30 seconds
Memory	2 MB	128-10,240 MB
Package Size	10 KB	1-50 MB
Network Access	None	Full internet access
Cold Start	Sub-millisecond	100-200+ ms
Price	$0.10/million invocations	$0.60/million + duration
Scale	10M+ requests/second	10K requests/second per region

CloudFront Functions Examples

/**
 * CloudFront Function: Viewer Request - URL Rewriting
 * Rewrite clean URLs to actual file paths
 */
function handler(event) {
    var request = event.request;
    var uri = request.uri;
    
    // Handle SPA routing - serve index.html for paths without extensions
    if (!uri.includes('.')) {
        // Check if path ends with / or has no extension
        if (uri.endsWith('/')) {
            request.uri = uri + 'index.html';
        } else if (!uri.split('/').pop().includes('.')) {
            request.uri = '/index.html';
        }
    }
    
    // Add file extension for API versioning
    // /api/v2/users -> /api/v2/users.json
    if (uri.startsWith('/api/') && !uri.includes('.')) {
        request.uri = uri + '.json';
    }
    
    return request;
}

When to Use Which

Security: AWS WAF and Shield Integration

CloudFront's security is deeply integrated with AWS's security services, providing layered protection from network to application level.

AWS Shield Integration:

All CloudFront distributions automatically receive AWS Shield Standard protection—free, always-on DDoS defense:

Protection against SYN/UDP floods, reflection attacks
Network-level attack mitigation
No configuration required

AWS Shield Advanced (paid, starting ~$3,000/month) adds:

Application-layer (L7) DDoS protection
24/7 access to AWS DDoS Response Team (DRT)
Cost protection—credits for scaling costs during attacks
Real-time metrics and reporting
Integration with AWS WAF managed rules

AWS WAF Integration:

AWS WAF provides web application firewall capabilities directly at the CloudFront edge:

AWS WAF Configuration

Terraform WAF

# AWS WAF Web ACL for CloudFront
resource "aws_wafv2_web_acl" "cloudfront_waf" {
  name        = "cloudfront-protection"
  description = "WAF rules for CloudFront distribution"
  scope       = "CLOUDFRONT"  # Must be CLOUDFRONT for CF distributions
  
  default_action {
    allow {}
  }
  
  # AWS Managed Rules - Core Rule Set
  rule {
    name     = "AWSManagedRulesCommonRuleSet"
    priority = 1
    
    override_action {
      none {}  # Use rule actions as-is
    }
    
    statement {
      managed_rule_group_statement {
        name        = "AWSManagedRulesCommonRuleSet"
        vendor_name = "AWS"
        
        # Exclude rules that cause false positives
        excluded_rule {
          name = "SizeRestrictions_BODY"
        }
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "CommonRuleSetMetric"
    }
  }
  
  # AWS Managed Rules - Known Bad Inputs
  rule {
    name     = "AWSManagedRulesKnownBadInputsRuleSet"
    priority = 2
    
    override_action {
      none {}
    }
    
    statement {
      managed_rule_group_statement {
        name        = "AWSManagedRulesKnownBadInputsRuleSet"
        vendor_name = "AWS"
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "BadInputsMetric"
    }
  }
  
  # Rate limiting rule
  rule {
    name     = "RateLimitRule"
    priority = 3
    
    action {
      block {}
    }
    
    statement {
      rate_based_statement {
        limit              = 2000  # requests per 5 minutes
        aggregate_key_type = "IP"
        
        scope_down_statement {
          # Only rate limit login endpoint
          byte_match_statement {
            search_string = "/api/auth/login"
            field_to_match {
              uri_path {}
            }
            positional_constraint = "STARTS_WITH"
            text_transformation {
              priority = 0
              type     = "LOWERCASE"
            }
          }
        }
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "RateLimitMetric"
    }
  }
  
  # Geo-blocking rule
  rule {
    name     = "GeoBlockRule"
    priority = 4
    
    action {
      block {}
    }
    
    statement {
      geo_match_statement {
        country_codes = ["RU", "CN", "KP"]  # Block specific countries
      }
    }
    
    visibility_config {
      sampled_requests_enabled   = true
      cloudwatch_metrics_enabled = true
      metric_name                = "GeoBlockMetric"
    }
  }
  
  visibility_config {
    cloudwatch_metrics_enabled = true
    metric_name                = "CloudFrontWAF"
    sampled_requests_enabled   = true
  }
}
 
# Associate WAF with CloudFront distribution
resource "aws_cloudfront_distribution" "cdn" {
  # ... other config ...
  
  web_acl_id = aws_wafv2_web_acl.cloudfront_waf.arn
}

Available AWS Managed Rule Groups

•Core Rule Set (CRS) — General web application protection, OWASP Top 10
•SQL Database — Protection against SQL injection attacks
•Known Bad Inputs — Blocks requests with known malicious patterns
•Linux/POSIX OS — Protects against Linux-specific exploits
•Windows OS — Protects against Windows-specific exploits
•PHP Application — PHP-specific vulnerability protection
•WordPress Application — WordPress-specific protection
•Amazon IP Reputation — Blocks requests from known malicious IPs
•Bot Control — Managed bot detection and mitigation (additional cost)

WAF Pricing

Advanced Caching Configuration

CloudFront's caching behavior is highly configurable through cache policies and origin request policies, enabling fine-grained control over what gets cached and what gets forwarded to origin.

Cache Policies:

Cache policies determine what's included in the cache key and TTL settings:

AWS Managed Cache Policies
Policy Name	Use Case	Key Characteristics
CachingOptimized	Static content	Long TTLs, no headers/cookies/query strings in key
CachingOptimizedForUncompressedObjects	Pre-compressed content	Like above, but doesn't normalize Accept-Encoding
CachingDisabled	Dynamic content	No caching, all requests to origin
Elemental-MediaPackage	Video streaming	Optimized for HLS/DASH manifest and segment caching
Amplify	Amplify Hosting	Configured for Amplify's caching patterns

Origin Request Policies:

Separate from cache policies, origin request policies control what CloudFront forwards to your origin when it needs to fetch content:

Custom Cache and Origin Request Policies

Terraform

# Custom cache policy for API responses
resource "aws_cloudfront_cache_policy" "api_cache" {
  name        = "API-Caching-Policy"
  comment     = "Cache API responses based on auth and accept headers"
  
  default_ttl = 300    # 5 minutes default
  max_ttl     = 3600   # 1 hour max
  min_ttl     = 0      # Respect Cache-Control: no-cache
  
  parameters_in_cache_key_and_forwarded_to_origin {
    # Include compression headers in cache key
    enable_accept_encoding_brotli = true
    enable_accept_encoding_gzip   = true
    
    # Include specific headers in cache key
    headers_config {
      header_behavior = "whitelist"
      headers {
        items = [
          "Authorization",        # Different cache per user
          "Accept-Language",      # Language-specific responses
          "CloudFront-Viewer-Country"  # Country-specific content
        ]
      }
    }
    
    # Include cookies in cache key
    cookies_config {
      cookie_behavior = "whitelist"
      cookies {
        items = ["session_id", "user_preferences"]
      }
    }
    
    # Include query strings in cache key
    query_strings_config {
      query_string_behavior = "whitelist"
      query_strings {
        items = ["page", "limit", "sort", "filter"]
      }
    }
  }
}
 
# Origin request policy - forward additional headers
resource "aws_cloudfront_origin_request_policy" "api_origin" {
  name    = "API-Origin-Policy"
  comment = "Forward necessary headers to API origin"
  
  headers_config {
    header_behavior = "whitelist"
    headers {
      items = [
        "Authorization",
        "Origin",
        "Access-Control-Request-Method",
        "Access-Control-Request-Headers",
        "X-Request-ID"
      ]
    }
  }
  
  cookies_config {
    cookie_behavior = "all"  # Forward all cookies to origin
  }
  
  query_strings_config {
    query_string_behavior = "all"  # Forward all query strings
  }
}
 
# Apply policies to cache behavior
resource "aws_cloudfront_distribution" "api" {
  # ... origin config ...
  
  default_cache_behavior {
    target_origin_id       = "api-origin"
    viewer_protocol_policy = "https-only"
    
    allowed_methods = ["DELETE", "GET", "HEAD", "OPTIONS", "PATCH", "POST", "PUT"]
    cached_methods  = ["GET", "HEAD"]
    
    cache_policy_id          = aws_cloudfront_cache_policy.api_cache.id
    origin_request_policy_id = aws_cloudfront_origin_request_policy.api_origin.id
    
    compress = true
  }
}

Cache Key Optimization

CloudFront Pricing Structure

CloudFront uses consumption-based pricing with regional variation. Understanding the cost structure is essential for budgeting and optimization.

Pricing Components:

CloudFront Pricing (US/Europe Region)
Component	Price Range	Notes
Data Transfer Out (first 10TB)	$0.085/GB	Decreases with volume
Data Transfer Out (10-50TB)	$0.080/GB	Volume tier pricing
Data Transfer Out (50-150TB)	$0.060/GB	Volume tier pricing
HTTP/HTTPS Requests	$0.0075-0.01/10K	Varies by protocol and region
Origin Shield Requests	$0.0090/10K	Additional for cache aggregation
Lambda@Edge Invocations	$0.60/million	Plus duration-based compute
CloudFront Functions	$0.10/million	Significantly cheaper than L@E
Field-Level Encryption	$0.02/10K requests	For encrypting specific fields

Cost Optimization Strategies:

Reducing CloudFront Costs

•Maximize cache hit ratio — Every cache hit avoids origin transfer and origin request processing. Use cache policies wisely.
•Enable compression — Brotli/Gzip compression reduces data transfer by 70-90% for text content. CloudFront compresses for free.
•Use CloudFront Functions over Lambda@Edge — 6x cheaper per invocation for simple transformations.
•Consider Price Class — CloudFront offers reduced price classes that limit edge locations to cheaper regions.
•Use AWS origins — Data transfer from AWS services to CloudFront is free. Only edge-to-viewer transfer costs.
•Committed use discounts — CloudFront Security Savings Bundle offers 30% savings for 1-year commitment.

Free Tier

CloudFront's free tier includes 1TB data transfer out and 10 million HTTP/HTTPS requests per month for the first 12 months. This covers most startup needs during early development and testing phases.

When to Choose CloudFront

CloudFront's value proposition centers on AWS integration. Use this framework to evaluate fit:

CloudFront Is Ideal When

•AWS-centric infrastructure — Origins in S3, ALB, API Gateway benefit from free transfer and native integration
•Unified AWS billing — Single bill, consolidated reporting, reserved capacity discounts
•AWS IAM integration required — Native IAM policies, cross-account access patterns
•AWS WAF/Shield needed — Deep integration with AWS security services
•Using AWS Amplify/CDK — First-class infrastructure-as-code support
•Private origins via VPC — CloudFront + VPC origins access private resources
•S3 Object Lambda — Transform objects on-the-fly during delivery

Consider Alternatives When

•Multi-cloud architecture — Cloudflare/Fastly work equally well with any origin
•Real-time purge required — CloudFront invalidation is slower than Fastly
•Developer experience prioritized — Cloudflare Workers has better DX
•Security-first requirement — Cloudflare's included DDoS/security is more comprehensive
•Unmetered bandwidth needed — Cloudflare's flat pricing may be cheaper
•Edge data storage — Cloudflare KV/R2 is more mature than Lambda@Edge storage
•Non-AWS origins — Egress from other clouds to CloudFront incurs costs

Page Complete

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