Cassandra is a relative latecomer in the distributed data-store war. It takes advantage of two proven and closely similar data-store mechanisms, namely Bigtable: A Distributed Storage System for Structured Data, 2006 (http://static.googleusercontent.com/external_content/untrusted_dlcp/research.google.com/en//archive/bigtable-osdi06.pdf) and Amazon Dynamo: Amazon's Highly Available Key-value Store, 2007 (http://www.read.seas.harvard.edu/~kohler/class/cs239-w08/decandia07dynamo.pdf). The following diagram displays the read throughputs that show linear scaling of Cassandra:

Like BigTable, it has a tabular data presentation. It is not tabular in the strictest sense. It is rather a dictionary-like structure where each entry holds another sorted dictionary/map. This model is more powerful than the usual key-value store and it is named a table, formerly known as a column family. The properties such as eventual consistency and decentralization are...