Architecture and Functionality
Axelar’s architecture is centered around gateway smart contracts, validators, and relayer services. Gateway smart contracts enable Axelar to communicate messages across all connected chains. Each EVM chain connected to the Axelar network has a Gateway contract deployed to it, which is used to pass messages from the Axelar network to the connected chain. The Gateway contract is controlled by a key, which is held jointly by all the Axelar validators through a multi-party cryptography scheme.
Validators in the Axelar network play two main roles. First, they participate in consensus on the Axelar network, producing blocks and validating transactions as with other proof-of-stake chains. Beyond this, Axelar validators also have additional duties as they are responsible for verifying all cross-chain activity being processed by the network. This requires validators to run nodes for Axelar-supported chains, and observe those external chains for activity.
Relayer services are a type of optional convenience services provided by Axelar. These are tasks that can be performed by anyone, and no form of trust is required to authorize or complete the task. These tasks are still important however, as they must be done by someone to enable successful cross-chain communication.
Developer Tools and Resources