Tech Matchups: Azure Key Vault vs Azure App Configuration
Overview
Picture your application as a fortified vault, where sensitive data and settings are secured. Azure Key Vault, launched in 2015, is the cryptographic stronghold—a managed service for storing secrets, keys, and certificates, used by 30% of Azure security customers (2024).
Azure App Configuration, introduced in 2019, is the dynamic ledger—a managed service for storing and managing application settings and feature flags, powering 15% of Azure’s configuration workloads.
Both are configuration titans, but their roles differ: Key Vault secures sensitive data, while App Configuration manages app settings. They’re vital for apps from finance to SaaS, balancing security with flexibility.
Section 1 - Data Types and Access
Key Vault stores secrets—example: add a secret:
App Configuration stores key-value pairs—example: add a setting:
Key Vault handles secrets (e.g., API keys), keys (RSA, EC), and certificates—think securing 1,000 DB credentials. App Configuration manages settings (e.g., timeouts) and feature flags—think enabling a beta feature for 10% of users. Key Vault uses RBAC and policies; App Configuration uses AAD and labels.
Scenario: Key Vault secures payment keys; App Configuration toggles UI features. Choose by data type.
Section 2 - Security and Compliance
Key Vault offers HSM-backed encryption—example: store a 2048-bit RSA key with FIPS 140-2 compliance. Supports access logging and key rotation—think auditing 10,000 secret accesses/month.
App Configuration encrypts data at rest—example: secure a connection string with AAD authentication. Supports versioning and snapshots but lacks HSM. Ideal for non-sensitive settings.
Scenario: Key Vault protects PCI-compliant keys; App Configuration manages public settings. Key Vault is security-first, App Configuration flexibility-first—pick by sensitivity.
Section 3 - Management and Cost
Key Vault is fully managed—example: 10,000 secret operations cost ~$0.03. Standard tier (~$0.50/vault/month) suits most; Premium adds HSM for ~$1/vault/month.
App Configuration is fully managed—example: 10,000 requests cost ~$0.10. Free tier includes 1,000 requests/day; Standard tier (~$4.80/month) supports 30,000 requests/day.
Practical case: Key Vault secures sensitive configs; App Configuration manages app settings. Key Vault is premium, App Configuration cost-effective—optimize by use case.
Section 4 - Use Cases and Ecosystem
Key Vault excels in security—example: secure 1,000 API keys for a fintech app. App Configuration shines in dynamic configs—think toggling 10 features for 1M users.
Ecosystem-wise, Key Vault integrates with AKS and App Service; App Configuration with Functions and Spring Cloud. Key Vault is security-focused, App Configuration developer-focused.
Practical case: Key Vault protects DB credentials; App Configuration enables A/B testing. Choose by purpose.
Section 5 - Comparison Table
| Aspect | Key Vault | App Configuration |
|---|---|---|
| Data | Secrets, keys | Settings, flags |
| Security | HSM, FIPS 140-2 | Encryption, AAD |
| Cost | ~$0.03/10K ops | ~$0.10/10K req |
| Management | Policy-driven | Label-driven |
| Best For | Sensitive data | Dynamic settings |
Key Vault suits sensitive data; App Configuration excels in dynamic configs. Choose by security needs.
Conclusion
Azure Key Vault and App Configuration are configuration powerhouses with distinct roles. Key Vault provides top-tier security for sensitive data like secrets and keys, ideal for compliance-driven apps. App Configuration offers flexible management of settings and feature flags, perfect for dynamic, developer-focused apps. Consider data type (sensitive vs. non-sensitive), security requirements (HSM vs. encryption), and management needs.
For secure credentials, Key Vault shines; for feature toggles, App Configuration delivers. Pair Key Vault with AKS or App Configuration with Functions for optimal results. Test both—Key Vault’s free tier or App Configuration’s free requests make prototyping easy.