AWS Case Studies: Solutions and Costs for Established Companies

1. Bank (1M customers)

Background

A regional bank with:

• 1 million customers
• 100,000 transactions/day
• Sensitive data
• Strict regulatory compliance

AWS Solution

• Applications: EKS (Kubernetes)

  • 20 nodes (m5.xlarge)
  • Auto Scaling
  • Cost: ~$3,000/month

• Database: Aurora

  • 3 instances (db.r5.xlarge)
  • 1TB storage
  • Multi-AZ
  • Cost: ~$2,500/month

• Storage: S3

  • 10TB of data
  • Glacier for archives
  • Cost: ~$300/month

• Security: WAF + Shield

  • DDoS protection
  • Cost: ~$3,000/month

Total Cost: ~$8,800/month

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2. Media (5M visitors/month)

Background

A news site with:

• 5 million visitors/month
• 10,000 articles
• Video streaming
• Dynamic content

AWS Solution

• Frontend: CloudFront + S3

  • 100TB transfer/month
  • 1TB storage
  • Cost: ~$1,000/month

• Backend: ECS Fargate

  • 10 services
  • 20 vCPU, 40GB RAM
  • Cost: ~$800/month

• Database: RDS

  • 2 instances (db.r5.large)
  • 500GB storage
  • Cost: ~$600/month

• CDN: CloudFront

  • 200TB transfer/month
  • Cost: ~$2,000/month

Total Cost: ~$4,400/month

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3. E-commerce (1M products)

Background

An international marketplace with:

• 1 million products
• 100,000 orders/day
• 10,000 sellers
• Multi-region

AWS Solution

• Application: EC2 Auto Scaling

  • 10 instances (c5.xlarge)
  • Multi-region
  • Cost: ~$2,000/month

• Database: Aurora Global

  • 4 instances (db.r5.xlarge)
  • 2TB storage
  • Cost: ~$4,000/month

• Storage: S3

  • 5TB of images
  • CloudFront
  • Cost: ~$500/month

• Cache: ElastiCache

  • 2 Redis clusters
  • Cost: ~$1,000/month

Total Cost: ~$7,500/month

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4. Enterprise SaaS (10,000 customers)

Background

A B2B platform with:

• 10,000 customers
• 100,000 users
• Sensitive data
• 99.99% SLA

AWS Solution

• Application: EKS

  • 15 nodes (m5.xlarge)
  • Multi-AZ
  • Cost: ~$2,250/month

• Database: RDS

  • 4 instances (db.r5.xlarge)
  • 1TB storage
  • Multi-AZ
  • Cost: ~$3,000/month

• Storage: S3

  • 2TB of data
  • Cost: ~$50/month

• Monitoring: CloudWatch

  • Logs and metrics
  • Cost: ~$200/month

Total Cost: ~$5,500/month

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Cost Comparison Table

Company Type	Main Solution	Monthly Cost	Key Points
Bank	EKS + Aurora	~$8,800	Security, compliance
Media	CloudFront + ECS	~$4,400	Performance, scale
E-commerce	EC2 + Aurora Global	~$7,500	Multi-region
Enterprise SaaS	EKS + RDS	~$5,500	High availability

Tips for Optimizing Costs:

1. For the Bank:

   • Use Reserved Instances
   • Right-size your clusters
   • Enable data compression
   • Use S3 Intelligent-Tiering

2. For the Media Company:

   • Optimize the CloudFront cache
   • Use media compression
   • Enable intelligent auto scaling
   • Optimize RDS queries

3. For E-commerce:

   • Use Spot Instances
   • Optimize Aurora replication
   • Enable multi-level caching
   • Use the CDN effectively

4. For Enterprise SaaS:

   • Use Reserved Instances
   • Right-size your clusters
   • Enable data compression
   • Use intelligent monitoring

Key Takeaways:

For established companies:

• Reliability is the top priority
• Costs are higher but justified
• Security is crucial
• Scaling must be robust