Cloud storage is classified as decentralized if the storage system is distributed around the world, and centralized if the storage system is singularly controlled.
In the centralized version, the storage system is maintained by the cloud controller, and it is operated by the central server in the cloud controller. All the hosts are allocated with only one storage system for storing the images, files, and data.
In the decentralized version, a group of clusters with different storage systems for different clusters are used. Therefore, the group of hosts in the cluster will use the storage system related to that cluster, but not the other storage system of the other cluster.
This provides higher levels of scalability, redundancy, and durability in decentralized architectures.
If a decentralized component is compromised or encounters a runtime error which is unrecoverable, the worst-case scenario is that the component goes offline, while the rest of the cloud continues to function normally. This design presents a fail-safe which increases cloud stability.