Decentralized vs. Distributed Systems
Decentralized systems are much more secure and unhackable as compared to centralized distributed systems, they are also relatively slower for the same reasons and characteristics.
Distributed systems use multiple nodes to distribute the load and data so that they can be scaled easily to serve more users. On the other hand, decentralized systems use multiple nodes to make sure there is no central point of control or failure. Both these approaches are fundamentally different from each other.
Recall from episode 1, that blockchains (or decentralized systems) are used to reach an agreement, on the state of data, among several parties, without the use of a centralized system or middlemen. To achieve this, decentralized systems have to replicate data across all the nodes. Even if some of the nodes are compromised, the network works normally.
For decentralized systems to work, a lot of communication is done among the nodes for broadcasting transactions and for getting consensus on the blocks. Also, each node then executes and commits each and every block to update the state of the blockchain.
However, in distributed systems, the load and data are partitioned among nodes. Not all the nodes have to process and store all the data, and this makes distributed systems relatively faster than decentralized systems.
In essence, while decentralized systems are much more secure and unhackable as compared to centralized distributed systems, they are also relatively slower for the same reasons and characteristics.