Rack Aware
Cassandra is Rack aware, meaning that it will try to position data in different racks, so that during a rack failure, there will be no data loss.
Highly Available
No Single Point Of Failure
Petabyte Database
Geographic Distribution
Data is replicated between different Datacenters and they can be geographically in different places. Each Datacenter has 100% of the data, however data is NOT immediately replicated between datacenters.