Popular Distributed Systems Articles

An idempotency key is a unique value attached to a request so a server can recognize repeated attempts to perform the same logical operation and avoid executing it more than once.

Splitting an application into services creates an important architectural problem: each service owns its data, but other services frequently need that data to complete their work .

Data management becomes one of the hardest parts of microservices architecture. Inside a monolith, multiple modules can share a database, execute joins, and update related records inside a single transaction. Once business capabilities become independent services, those assumptions no longer hold.

Idempotency allows the same logical operation to be executed multiple times without producing additional side effects. Deduplication identifies repeated requests, commands, or events and prevents them from being processed as new work.

CAP theorem defines three guarantees in distributed systems: consistency , availability , and partition tolerance, with the constraint that only two can be fully satisfied during a network partition. In real-world architectures, partition tolerance is unavoidable, which forces systems to choose betw

Consistency patterns describe how systems behave when multiple users, services, or processes read and write shared data at the same time.

The CAP theorem explains one of the most important trade-offs in distributed system design: when a network partition happens, a system must choose between consistency and availability . This article explains what CAP really means, why partition tolerance is unavoidable in distributed systems, and ho

Consistency in system design describes how fresh and correct data should be when users, services, or replicas read it after a write. Some systems require every read to reflect the latest committed value, while others can tolerate stale data for better latency, availability, or scalability.

Service Discovery is the mechanism that allows applications to find the network locations of other services dynamically. Instead of hardcoding IP addresses and ports, a service asks a discovery system where another service is currently available.

A Lamport clock is a logical clock used in distributed systems to establish an ordering between events without relying on synchronized physical clocks. Each process maintains a counter that increases as events occur and is exchanged when processes communicate.

A vector clock is a logical clock used in distributed systems to track causal relationships between events. Instead of relying on physical timestamps, each participant maintains a set of counters describing the events it has observed.

A quorum is the minimum number of participants in a distributed system that must agree or respond before an operation can be considered valid.

Leader election is a coordination mechanism used in distributed systems to select one node as the leader responsible for performing specific tasks or making certain decisions on behalf of a group.

A distributed lock is a coordination mechanism used to ensure that only one process, server, container, or worker can perform a particular operation on a shared resource at a time.

Eventual consistency is a consistency model in which different replicas or services may temporarily contain different versions of the same data, but if updates stop, all replicas eventually converge to the same state .

Distributed systems often run multiple instances of the same component for availability and horizontal scalability. Some responsibilities, however, must have exactly one active owner : assigning partitions, scheduling recurring jobs, promoting database replicas, updating cluster metadata, or coordin

The CAP theorem describes a fundamental constraint in distributed data systems : during a network partition, a system cannot guarantee both strong consistency and full availability for every request.

Distributed systems often store the same data on multiple nodes to improve availability, fault tolerance, read scalability, and geographic performance . Replication introduces a difficult question: when one copy changes, how quickly must every other copy reflect that update?

A distributed system is a group of independent computers that communicate over a network and cooperate to provide one service. Applications use distributed architectures to handle more traffic, improve availability, process data closer to users, and continue operating when individual components fail

Distributed transactions coordinate one business operation across multiple services, databases, queues, or external systems. Unlike a local database transaction, no single transaction manager automatically guarantees that every participating component commits or rolls back together.