Where transactions are stored in canton domain?

Hi team,

Where are the encrypted transaction stored in a Canton domain? Is it in the sequencer or somewhere else?

If the transactions are stored in sequencer, does it mean that when we scale out the mediators, we can just store in Memory as the mediators won’t be storing any important information?

Thanks and regards,
Jean-Paul

It’s in the system underlying the sequencer, yes. So if you are running Canton with its integration with Besu, for example, the encrypted transactions are stored on the Ethereum Blockchain exposed by the Besu clients.

The sequencers will store timestamped & serially ordered “encrypted messages”. Some of these encrypted messages contain transactions. However, the messages are only stored for the guaranteed ordered multi-cast. The domain operator might at some point prune the transactions (to keep the resource usage bounded).

However, reading your question in between the lines, you are asking whether you can run a production mediator without using a database store. The answer is no, you can’t. The mediator requires a database to store some information such as its identity, keys and the receipts it received from the participants (for auditability purposes).

Thanks for the precision !