AWS Pro

Defining Serverless

A service is considered serverless when it meets these key criteria:

1. No Server Management

   • Provider handles patches and OS updates

   • Example: AWS Lambda

2. Flexible Scaling

   • Automatic scaling based on traffic

   • Scaling within defined boundaries

3. Built-in High Availability

   • Default fault tolerance

   • Inherent availability features

4. Scale to Zero Capability

   • No idle capacity

   • No costs when inactive

Note on "Serverless" Services

Some AWS services labeled as "serverless" (e.g., Aurora Serverless, Neptune Serverless) may not fully meet all criteria, particularly zero-scaling. These services represent the best-fit options for serverless applications despite limitations.

How AWS resources operate across multiple regions

Global Services (No Region Concept)

• Route 53 - DNS service operates globally

• CloudFront - CDN with global edge locations

• AWS Global Accelerator - Global network optimization

• IAM - Identity and Access Management (users, roles, policies)

• AWS Organizations - Account management across all regions

• AWS WAF - Web Application Firewall (when used with CloudFront)

Cross-Region Capable Resources

Storage & Data:

• S3 Cross-Region Replication - Replicate objects between regions

• DynamoDB Global Tables - Multi-region, multi-master replication

• RDS Cross-Region Read Replicas - Read replicas in different regions

• EBS Snapshots - Can be copied to other regions

• AMIs - Can be copied to other regions

Networking:

• VPC Peering - Connect VPCs across regions

• Transit Gateway Inter-Region Peering - Connect Transit Gateways

• Direct Connect - Can connect to multiple regions

• Route 53 Resolver - DNS forwarding across regions

Security & Compliance:

• AWS Certificate Manager - SSL/TLS certificates (global for CloudFront)

• AWS Secrets Manager - Cross-region secret replication

• AWS Config - Compliance monitoring across regions

• CloudTrail - Can log to S3 buckets in different regions

Management & Monitoring:

• CloudWatch - Cross-region dashboards and alarms

• AWS Systems Manager - Parameter Store cross-region replication

• AWS Backup - Cross-region backup copying

Development & Deployment:

• CodePipeline - Can deploy across regions

• CloudFormation StackSets - Deploy stacks to multiple regions

• AWS Lambda@Edge - Functions run at CloudFront edge locations