Mastodon is not decentralized.

Hagen Hübel
2 min readDec 28, 2022

I always shudder when people talk about a “decentralized social network” when they want to explain Mastodon.

Please stop to call Mastodon a Decentralized Social Network. It is not.

Mastodon is not decentralized at all from my point of view. Every node/server is completely centralized! If the node provider or node admin shuts down or wants to lock people out, it’s easy to do. And if the Node operator wants to rephrase the tweet from someone, feel free. This can be done directly with SQL in the underlying database, without the need to take any further action and without users being informed, and most importantly, without any other entity preventing this fraud!

Mastodon is simply “only” sharding, with each shard managing its own user accounts and rules. But decentralization is something completely different.

A database shard, or simply a shard, is a horizontal partition of data in a database or search engine. Each shard is held on a separate database server instance, to spread load.

Mastodon would be decentralized if:

a) the accounts would be really decentralized: one account distributed over the whole system

b) the contents of each Mastodon server would be distributed decentralized over all other servers and the servers themselves would rather take a validator role over the persistence, consistency and validity of the data, so that a fraudulent node operator (or bad admin) could not falsify or lock out the contents.

Instead, every user has to register multiple accounts per every node server where they want to participate. Although it is possible to link multiple accounts to one specific account later, this is cumbersome, error-prone, misleading, and not following good practices.

If one Node operator would decide to give up (or if they just die, to draw an extreme example), all community contributions will be lost unless further backup strategies have been prepared and kept up to date.

In a fully decentralized network, multiple nodes would keep a copy of the data while multiple validators would care for data integrity. If we would put on a token economy, the community (= normal users) would delegate their trust in the form of tokens to specific validators, while fraudulent validators would face punishment and get locked out of the system without leaving any damage to the system. This would be real decentralization:

  • it protects users from fraud
  • it protects content from manipulation
  • it protects contributors from data loss

The model of Mastodon is probably exactly the most simplified version of a distributed network as described at the beginning so that just per server a chief can act and control the content on this server. But that is then absolutely no decentralization! Here a completely wrong picture is drawn.

Please stop to call Mastodon a Decentralized Social Network. It is not.