What is Service Mesh (e.g., Istio)?

Updated Apr 28, 2026

Short answer

A dedicated infrastructure layer for handling service-to-service communication, providing security and observability.

Deep explanation

As systems scale, maintaining consistency and resilience becomes harder. Patterns like Sagas manage distributed transactions without traditional locks. Circuit breakers prevent cascading failures by 'tripping' when a service is unhealthy, allowing it time to recover.

Real-world example

Netflix uses Hystrix/Resilience4j to ensure that if the 'Recommendations' service is slow, the user still sees their 'Watchlist'.

Common mistakes

  • Implementing Sagas for every simple cross-service operation.

Follow-up questions

  • What is a 'fallback' method?
  • How do you handle data consistency in Sagas?

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