interservice

Interservice refers to the communication and coordination between distinct services in a distributed software system, typically within microservices or service-oriented architectures. It describes how services call each other, share data, and coordinate actions to fulfill business processes while maintaining loose coupling and independent deployment.

Communication patterns: Interservice calls can be synchronous, where a caller waits for a response (common protocols include REST over HTTP and gRPC), or asynchronous, where messages are transmitted without an immediate reply (for example via message queues like RabbitMQ or event streams like Apache Kafka). Synchronous patterns tend to be simpler to model, while asynchronous patterns improve resilience and scalability but complicate ordering and consistency.

Data and transactions: Each service usually owns its own data store, enabling autonomy but creating cross-service consistency challenges. Distributed transactions are generally avoided in favor of eventual consistency. When cross-service consistency is required, patterns such as sagas with compensating actions or choreography are used to coordinate long-running processes.

Architecture and deployment: Interservice communication supports independent deployment and fault isolation. Key infrastructure elements include service discovery, API gateways, and service meshes that manage traffic routing, resilience, and security. Sidecar proxies (for example Envoy) are commonly used in service meshes to handle mTLS, retries, and tracing without code changes.

Security and governance: Security involves authentication and authorization across services, often using token-based schemes and mutual TLS. Governance concerns include versioning, contract stability, and clear interface definitions (APIs or events) to minimize breaking changes.

Testing and observability: Practices include contract testing (consumer-driven contracts), integration tests, and end-to-end tests. Observability relies on distributed tracing, centralized logging, metrics, and tracing systems to diagnose failures across service boundaries.