Overview
Who verifies cross-chain activity, on consensus and Amplifier chains.
Before Axelar approves a cross-chain message, it checks that the message really happened on its source chain. Who does that checking depends on how the source chain is connected to Axelar.
| Consensus chains | Amplifier chains | |
|---|---|---|
| Verified by | Axelar validators | Amplifier verifiers |
| Must be an Axelar validator | Yes | No |
| Software | vald and tofnd, alongside your validator's axelard | ampd, tofnd and a handler per chain |
| How you join | Register as a chain maintainer for each chain | Bond AXL, register chain support and get authorized |
| Guide | Verify consensus chains | Become an Amplifier verifier |
Consensus chains
Consensus chains are the EVM chains connected to Axelar before Amplifier. Axelar validators verify them as part of their validator duties: each validator chooses which chains to support, runs a node for each of them, and registers as a maintainer of those chains. Its vald process then votes on the chain's events.
To verify consensus chains, first set up your Axelar validator, then follow Verify consensus chains.
Amplifier chains
Chains connected through Amplifier each have their own verifier set. Verifiers run ampd, which votes on source-chain events and signs outgoing messages for the chains they support. Being an Axelar validator is not required; if you run both, use separate Axelar nodes and tofnd instances for each.
To verify Amplifier chains, follow Become an Amplifier verifier.
External chain nodes
Both kinds of verification need your own node for each chain you support. See External Chain Nodes for why that node should be your own, and for setup guides for each chain.