Nomad is an interoperability protocol for generalized message passing. We leverage an optimistic mechanism. There are no validators, and there is no blockchain. We're deployed as smart contracts between two chains, and has a lightweight off-chain component. This allows us to have less overhead and be more cost-efficient than other interoperability protocols.

Nomad Features

  • Users can bridge tokens between chains
  • Asset issuers can deploy tokens across chains
  • DAOs can facilitate cross-chain governance proposals
  • Developers can build native cross-chain applications

How does Nomad work?

Nomad enables applications to send data between chains and rollups. Applications interact with Nomad core contracts to enqueue messages to be sent, after which off-chain agents verify and ferry these messages between chains.

In order to ensure that message-passing is secure, Nomad uses an optimistic verification mechanism, inspired by fraud-proof based designs like optimistic rollups. This makes Nomad more secure, cheaper, and easier to deploy compared to validator / proof-of-stake based interoperability protocols.

On-chain and Off-chain Components

The Nomad protocol consists of two core components, on-chain smart contracts and off-chain agents:

  • On-chain smart contracts implement Nomad's messaging API on-chain, enabling developers to enqueue messages and access replicated state on different chains.
  • Off-chain agents secure and relay state across chains, forming the backbone of the messaging layer.

Developers need not interface with off-chain agents directly, as the core contracts enforce logic around optimistic verification and ensure messages are securely transmitted.

Optimistic Verification

Nomad uses an optimistic verification mechanism, which is patterned after optimistic systems. It sees an attestation of some data, and accepts it as valid after a timer elapses. While the timer is running, honest participants (ie. Watchers) have a chance to respond to the attestation and submit fraud proofs.

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