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Replica

PreviousHomeNextXAppConnectionManager

Last updated 2 years ago

The Replica is the core contract deployed on all chains that wish to receive inbound messages. It serves as the "inbox" for all messages sent from a specific . For example, the from Ethereum to Moonbeam is generated by deploying a Home on Ethereum, and an Ethereum Replica on Moonbeam.

Updates on the Replica

Before accepting an update, a Replica places it into a queue of pending updates. Each update must wait for some time parameter () before being accepted. While a Replica cannot know that an update is certainly valid, the dispute window guarantees that fraud is publicly visible on the Home before being accepted by the Replica.

In other words, the security guarantee of the system is that all fraud may be detected by any participant and published via a proof on-chain during the window to react. Therefore updates that are not flagged by are sufficiently trustworthy for the Replica to accept.

(contract code)
Home contract
uni-directional channel
the optimistic dispute window
Watchers