What are the two types of replication strategies in Cassandra?

Cassandra provides two primary replication strategies to determine how data is stored across the nodes in a cluster: SimpleStrategy and NetworkTopologyStrategy.

SimpleStrategy is used for single datacenter deployments. It assumes a straightforward configuration where data is replicated across nodes without considering the topology of the network. It typically suffices for simpler use cases where the application runs in a single datacenter.

On the other hand, NetworkTopologyStrategy is designed for more complex environments involving multiple datacenters. This strategy allows for configuring different replication factors for different datacenters, enabling more efficient data replication and facilitating better fault tolerance. This is especially crucial for applications requiring high availability across geographical locations, as it enables the system to maintain data consistency and availability even if one datacenter goes down.

The correct answer highlights the need for understanding how data is distributed in Cassandra, which is key for efficient performance and scalability. The other options do not accurately represent the types of replication strategies available in Cassandra, as they either mention incorrect terms or combine unrelated concepts.