cassandra-non-centralized structure storage system

Cassandra is a http://www.aliyun.com/zixun/aggregation/14305.html "> Distributed Storage System that can manage very large amounts of structured data distributed across many commercial server nodes, Provides high availability services with no single point of failure. The Cassandra goal is to run on hundreds of base nodes, which may be distributed across different data centers. On this scale, large and small components often fail. Cassandra's management of these failed persistent states encourages the reliability and scalability of the software system to rely on this service. While Cassandra resembles a database in many ways and shares many design and related implementation strategies, Cassandra does not support a complete relational data model; Instead, it provides customers with a simple data model that supports dynamic control of data layouts. The Cassandra System is designed to run on inexpensive commercial hardware with high write throughput processing without sacrificing read efficiency.