Whats the difference between Paxos and W+R>=N in Cassandra?

Posted by user1128016 on Stack Overflow See other posts from Stack Overflow or by user1128016
Published on 2012-08-28T09:37:04Z Indexed on 2012/08/28 9:38 UTC
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algorithm

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cassandra

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distributed-computing

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zookeeper

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paxos

Dynamo-like databases (e.g. Cassandra) provide ability to enforce consistency by means of quorum, i.e. a number of synchronously written replicas (W) and a number of replicas to read (R) should be chosen in such a way that W+R>N where N is a replication factor. On the other hand, PAXOS-based systems like Zookeeper are also used as a consistent fault-tolerant storage.

What is the difference between these two approaches? Does PAXOS provide guarantees that are not provided by W+R>N schema?

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