> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hyperlane.xyz/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

The Hyperlane protocol decouples the transport layer from the security layer of cross-chain message passing. To run a deployment, it relies on offchain agents that observe onchain activity and carry out either the transport or security aspects of the protocol.

These agents are implemented in Rust and distributed as Docker images and binaries.

1. [Relayers](/docs/protocol/agents/relayer) fulfill the message transport requirement of the protocol. They aggregate off-chain security metadata for the [`IInterchainSecurityModule` interface](/docs/protocol/ISM/modular-security#core-concepts) and deliver messages to their recipients.
2. [Validators](/docs/protocol/agents/validators) fulfill the security requirement of the protocol, as part of the [Multisig ISM](/docs/protocol/ISM/standard-ISMs/multisig-ISM) or the [Hyperlane AVS](/docs/protocol/ISM/economic-security/hyperlane-avs), by attesting to the validity of [Mailbox](/docs/protocol/core/mailbox) messages and making their signatures available to a relayer.