So you want a Decentralized Database?
A Blockchain is often referred to as a decentralized database. What do people mean when they say "decentralized database"? What are the core features of a decentralized computer system? Are all blockchains decentralized databases? Do other, non-blockchain, decentralized databases exist? This blog attempts to answer these questions.
From a user perspective, the choices the decentralized system makes in these categories defines your experience with the decentralized system. How is the accepted, "true" copy determined? Which node should you copy? How easy is it for you to maintain your own independent copy? How expensive is it for you to get your writes on the generally accepted, "true" copy? Who or what decides the accepted, "true" copy? What do you do if you get a bad copy? How often are there bad copies? Can an ill intentioned person mess up your experience?
Distributed software systems are not the same as decentralized software systems. However, a decentralized system is a class of distributed system. Distributed systems describe software where load is distributed among many computers. The key differentiating feature between distributed and decentralized systems is that in distributed systems, it is assumed that each node or instance in a distributed system is trusted. In a decentralized system, nodes can be owned by untrusted parties.
