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AWS Compute

Local Zones

Place compute, storage, and database resources closer to large population centers

AWS Local Zones are infrastructure deployments that place a subset of AWS services in metropolitan areas outside of AWS Regions. They allow you to run latency-sensitive applications closer to large population centers - delivering single-digit millisecond latency to end users - while still using the same AWS APIs, tools, and console.

How Local Zones Work

A Local Zone is an extension of an AWS Region. It appears as an additional Availability Zone in the VPC console. You opt-in to enable a Local Zone, create a subnet in it, and launch instances there.

  • Local Zones are connected to the parent region via AWS's private network with high-bandwidth, low-latency links
  • Instances in a Local Zone have low-latency access to users in the same metro area via the public internet
  • The parent region handles the control plane, IAM, and services not available in the Local Zone
  • Available in 30+ cities worldwide: Los Angeles, Dallas, Chicago, Miami, Atlanta, Denver, Seattle, and international cities

Available Services

Local Zones support a subset of AWS services. Core services available include:

  • Compute: EC2 (select instance types), Auto Scaling
  • Storage: EBS (gp2, io1), EFS
  • Networking: VPC, subnets, security groups, Direct Connect, ALB
  • Database: RDS (MySQL, PostgreSQL, MariaDB), ElastiCache
  • Containers: ECS, EKS
  • Not available: Lambda, S3, most managed services. These continue to run in the parent region.
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For services not available in the Local Zone, your application makes a call back to the parent region. Design your architecture so latency-critical operations use Local Zone resources and less time-sensitive operations use the parent region.

Use Cases and Architecture Patterns

  • Media and entertainment: real-time video production, live streaming ingest, content creation tools for studio/broadcast teams in major cities
  • Gaming: low-latency game servers for players in a specific metro area
  • Financial trading: regional trading applications with sub-10ms order execution for local exchanges
  • Healthcare: imaging applications where DICOM workloads need to stay within a city for data residency or latency reasons
  • Hybrid deployments: extend existing VPCs into a city without setting up an Outposts rack
Local ZonesOutpostsWavelength
LocationAWS-operated, major citiesYour own facilityInside telecom carrier
Target userMetro end users (internet)On-premises systems5G mobile devices
Infrastructure ownerAWSYou (managed by AWS)Carrier (managed by AWS)
SetupOpt-in, create subnetAWS ships rack to youOpt-in, create subnet
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Interview Focus Points

  • 1What is a Local Zone and how does it differ from an Availability Zone?
  • 2Local Zones vs Outposts vs Wavelength - when would you choose each?
  • 3What services are NOT available in Local Zones and how do you architect around this?
  • 4How do you enable and use a Local Zone in your VPC?