Consistent Hashing medium
Why is Consistent Hashing considered 'Coordination Free' for routing?
- A Because it relies on a centralized hardware load balancer to manage all incoming traffic and internal routing decisions.
- B Because it ignores the underlying TCP protocol and communicates via a custom, lightweight point-to-point UDP stream.
- C Because it allows for permanent split brains where divergent nodes can independently process conflicting client data.
- D Because any client with the Ring Map can independently calculate the correct destination for any key without asking a master node.
Answer: D. Because any client with the Ring Map can independently calculate the correct destination for any key without asking a master node.
In Consistent Hashing, 'Math is the Coordinator'. Because the hash function is deterministic and public, any client (or node) can calculate `Hash(Key)` and map it to the ring to find the owner. This eliminates the need for a 'Metadata Server' or 'Master' lookup for every request, removing a critical bottleneck and allowing the system to scale to massive request volumes.
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Get the appRelated questions
- In a 'Smart Client' architecture (e.g., modern Cassandra drivers), how does the client find the right node?
- When a new node (Node X) joins the ring, where does it acquire its initial data from?
- Google's Maglev hashing algorithm (used in their Network Load Balancers) differs from standard Consistent Hashing rings. How does it generate the lookup table?
- Virtual Nodes improve balance but increase metadata size (Memory). How does 'Multi-Probe Consistent Hashing' achieve good balance without VNodes?
- In the Chord DHT protocol (a P2P consistent hashing implementation), naive lookups are O(N). How does Chord optimize this to O(log N)?
- Which of these systems is a famous user of Consistent Hashing?