Microservices architectures dramatically increase attack surface compared to monolithic applications. Each service represents a potential entry point, and inter-service communication creates numerous channels that attackers could exploit. Comprehensive security requires multiple defensive layers working together—API gateways, service mesh security, authentication and authorization, and zero trust principles.
API Gateway Security
API gateways provide centralized security enforcement at the architecture perimeter. Rate limiting prevents abuse and DDoS attacks. Request validation blocks malformed or malicious inputs. Authentication ensures only authorized clients access services. Web application firewall (WAF) rules filter common attack patterns. This centralized approach simplifies security policy management while protecting backend services.
- Implement rate limiting per client to prevent individual users from overwhelming systems
- Validate request schemas rigorously before forwarding to backend services
- Use OAuth 2.0 and JWT tokens for stateless authentication across services
- Enable CORS policies carefully to prevent unauthorized cross-origin requests
- Log all gateway requests for security monitoring and incident investigation
Service-to-Service Security
Internal service communication requires security even within supposedly trusted networks. Mutual TLS (mTLS) encrypts traffic and authenticates both parties in each connection. Service mesh implementations like Istio automate mTLS configuration. Zero trust principles assume no network is trustworthy, requiring authentication and authorization for every request regardless of source.
Secrets Management
Microservices need credentials for databases, external APIs, and other services. Hardcoding secrets or storing them in code repositories creates severe vulnerabilities. Centralized secrets management systems like HashiCorp Vault or cloud provider solutions provide secure storage, automatic rotation, and audit trails. Dynamic secrets that expire automatically limit damage from compromised credentials.