# Hybrid edge placement decision matrix (AWS)

Pick **where compute runs** — Region, Local Zone, Wavelength, or Outposts — before
you size instances. This is **placement and connectivity**, not the EC2-vs-Lambda
economics covered in the [hybrid compute post](/blog/hybrid-compute-ec2-serverless-cost-efficiency/).

> Reflects mid-2026 AWS edge portfolio. **Local Zones** are AWS-owned metro
> extensions of a parent Region. **Outposts** are AWS-managed hardware in *your*
> datacenter or colo. **Wavelength** embeds AWS compute in telco 5G networks.
> Confirm Local Zone and Wavelength availability per metro before architecture sign-off.

## 1. "What is the latency or residency constraint?"

| Constraint | First choice | Fallback |
|------------|--------------|----------|
| Metro users need <15 ms RTT to API | **Local Zone** in that metro | CloudFront + regional API if workload is cacheable |
| Data must stay on customer-owned floor | **Outposts** rack or server | Local Zone if residency law allows AWS-operated metro site |
| 5G handset / MEC use case with carrier | **Wavelength Zone** | Outposts in telco POP only if Wavelength unavailable |
| Global users, 50–200 ms acceptable | **Parent Region** + CloudFront | Do not buy edge hardware |

**Opinionated default:** **Local Zones before Outposts** when AWS-operated metro
infrastructure satisfies compliance. Outposts when the auditor requires hardware
on your raised floor or you need physical HSM proximity.

## 2. Service availability reality check

| Need | Local Zone | Outposts | Wavelength |
|------|------------|----------|------------|
| Full RDS / Aurora fleet | Limited — check [Local Zone services](https://aws.amazon.com/about-aws/global-infrastructure/localzones/features/) | Broader on Outposts rack | Subset — latency-sensitive only |
| EKS worker nodes | Often yes | Yes | Yes for edge pods |
| Direct Connect handoff | Yes (metro) | Yes (customer site) | Via carrier |
| Operated by | AWS | AWS manages; you host | AWS + telco partner |

## 3. When NOT to buy edge infrastructure

| Situation | Better path |
|-----------|-------------|
| Read-heavy API with cacheable responses | CloudFront + regional ALB |
| Batch ETL | Region — latency irrelevant |
| "We might need low latency someday" | Measure p99 from Region first |
| No carrier partnership for 5G | **Do not** deploy Wavelength |

## Related artifacts

- [Hybrid connectivity checklist](./hybrid-connectivity-checklist.md)
- [Latency vs cost worksheet](./latency-cost-worksheet.csv)

## Related posts

- [Hybrid & edge on AWS](/blog/aws-hybrid-edge-integration-outposts-local-zones-wavelength-2026/)
- [VPC networking best practices](/blog/aws-vpc-networking-best-practices-for-production/)
- [Data residency guide](/blog/aws-data-residency-sovereignty-guide-2026/)