CAP Theorem
The definitive proof that distributed networks under partition states must trade consistency for availability.
What you'll learn
- Consistency
- Availability
- Partition Tolerance
TL;DR
The definitive proof that distributed networks under partition states must trade consistency for availability.
Visual System Topology
CAP Theorem Constraints
Concept Overview
The CAP Theorem states that a distributed system can only guarantee two out of three properties: Consistency, Availability, and Partition Tolerance.
Since network partitions (P) are inevitable in distributed systems, you must choose between Consistency (C) and Availability (A). This fundamental trade-off shapes how distributed databases are designed.
Key Architectural Pillars
Consistency
All nodes see the same data at the same time. A read returns the most recent write.
Availability
Every request receives a response, even if some nodes are down. System remains operational.
Partition Tolerance
System continues to operate despite network partitions (nodes can't communicate). Required in distributed systems.