Cost Calculation & Optimization

1. Cost of Each Service

• Amazon VPC: VPC does not charge for creating and using basic components such as VPC, subnet, ACL, and security groups. However, using public IP addresses or Elastic IPs may incur costs

• AWS IAM: IAM is provided for free. Users can create and manage users, groups, and access permissions without additional costs

• Amazon EC2 with t2.medium instance:

  • The t2.medium instance provides 2 vCPUs and 4 GB RAM
  • The On-Demand cost for this instance in the ap-southeast-1 region is approximately $0.0464 per hour

• Amazon DocumentDB (db.t3.medium instance):

  • The db.t3.medium instance provides 2 vCPUs and 4 GB RAM
  • The On-Demand cost for this instance in the ap-southeast-1 region is approximately $0.078 per hour
  • Total monthly cost (720 hours): 720 hours x $0.078/hour = ~$56.16
  • Storage: $0.10/GB-month
  • Backup: $0.02/GB-month

• Amazon CloudFront:

  • Cost depends on data transfer and the number of requests
  • For example, data transfer out (First 10 TB per month) costs $0.085/GB
  • HTTP/HTTPS requests: $0.0075 per 10,000 requests

Here is an estimated cost table for each AWS service in the ap-southeast-1 region:

2. Cost Optimization

2.1. Cost Monitoring and Management

• Use AWS Cost Explorer: Monitor real-time costs to control resource usage
• Set Billing Alerts: Configure alerts via AWS Budgets to receive notifications when costs exceed a specified threshold
• Leverage AWS Free Tier: If new to AWS, take advantage of the free tier services available for the first 12 months

2.2. Optimizing EC2 Costs

• Choose the right instance type: If the workload is not too high, use t3.medium instead of t2.medium, as t3 offers better performance at a similar price
• Use Spot Instances: For non-continuous workloads, Spot Instances can reduce costs by up to 90% compared to On-Demand
• Implement Auto Scaling: Set up an Auto Scaling Group to dynamically adjust the number of EC2 instances based on demand, preventing resource wastage
• Use Reserved Instances / Savings Plans: If committing to EC2 usage for 1 or 3 years, Reserved Instances or Savings Plans can save up to 72% compared to On-Demand pricing
• Turn off unused instances: Shut down EC2 instances when not needed to reduce costs

2.3. Optimizing Amazon DocumentDB Costs

• Reduce the number of replicas: DocumentDB can have multiple replicas for better read performance, but if unnecessary, keep only 1 primary instance to save costs
• Use Auto Scaling Storage:: DocumentDB automatically scales storage, but regularly monitoring and deleting unnecessary data can prevent extra costs
• Manage backups wisely: Amazon DocumentDB provides free backup storage equal to the primary storage size. Additional backups are charged $0.02/GB-month, so keep only necessary backups
• Use Reserved Instances: If using DocumentDB long-term, Reserved Instances can save up to 60% on costs

2.4. Optimizing Amazon CloudFront Costs

• Enable Compression and Caching: Use Gzip/Brotli compression to reduce data transfer size, saving bandwidth costs
• Use Regional Edge Caches: CloudFront caches content closer to users, reducing the load on the origin server and cutting data transfer costs
• Reduce unnecessary requests: Optimize static files (CSS, JS, images) and implement Lazy Load to request resources only when needed
• Leverage CloudFront Free Tier: AWS provides 1TB of free data transfer per month for the first year. If traffic is low, use Free Tier benefits to lower costs

2.5. Optimizing VPC and IAM Costs

• Minimize Elastic IP usage: Elastic IPs are free when attached to a running instance. If not in use, release them to avoid a $0.005/hour charge
• Remove unused resources: Regularly check and delete subnets, security groups, NAT Gateways, and VPN Gateways that are no longer needed to avoid unnecessary costs
• Manage IAM access: Limit the creation of IAM Users and Roles, granting access only when necessary to reduce security risks