Welcome to the course

In this course, you will learn the fundamentals of Avalanche Interchain Messaging (ICM) and set up cross-chain communication infrastructure using Console tools.

Why Take This Course?

A significant innovation in blockchain is the development of multi-chain systems, like Avalanche, which provide a significant improvement in scalability, interoperability, and flexibility. At the core of these multi-chain systems is the ability to run multiple blockchains that communicate. Each chain's VM is optimized for specialized use cases, thereby boosting the network's overall performance.

Cross-chain communication is a crucial building block of multi-chain systems. Avalanche Interchain Messaging (ICM) and Avalanche Warp Messaging (AWM) provide a native, trustless way to send messages between any Avalanche L1s.

Course Content

Below you can find a 30 minute recording of a presentation about Avalanche Warp Messaging and Teleporter. This summarizes the content of the first chapters:

Interoperability

In the first section, we cover basic concepts of interoperability in multi-chain systems. You will learn about examples of interoperability between blockchains and the terms "source," "destination," and "message."

Avalanche Warp Messaging

In this section, we look at the low-level messaging primitive that powers cross-chain communication on Avalanche. You will learn about the warp message format, BLS signatures, validator signing, and how messages flow between chains.

ICM Protocol

Here we dive into the Interchain Messaging protocol layer built on top of AWM. You'll learn about TeleporterMessenger, message encoding/decoding, sending and receiving messages, and the TeleporterRegistry for version management.

ICM Infrastructure Setup

In this hands-on section, you'll use Console tools to deploy the full ICM infrastructure on your L1: TeleporterMessenger, TeleporterRegistry, and a relayer.

Your First Cross-Chain Message

Put it all together by deploying demo contracts and sending your first cross-chain message between Fuji C-Chain and your L1.

Relayer Deep Dive

Finally, we take a deeper look at relayer configuration, restricting relayers, and the economics of incentivizing message delivery.

What You'll Need

• An L1 deployed on Fuji testnet — If you haven't deployed one yet, see the L1 Architecture course
• Core Wallet connected to both Fuji C-Chain and your L1
• Test AVAX for gas fees (get some from the Fuji faucet)

Prerequisites

Avalanche

This course is meant for people with a solid understanding of the basic concepts of Avalanche. You should be familiar with these concepts:

• Virtual Machines: What they are and what VM customization means
• Avalanche L1s & Blockchains: What the difference between a VM, Blockchain, and an Avalanche L1 is

If any of this is unclear, we strongly recommend taking the Avalanche Fundamentals and Multi-Chain Architecture courses first.

Software Development

• Solidity: Familiarity with Solidity concepts. You won't write any contracts in this course, but you'll read contract interfaces and understand how cross-chain contracts work.

Learning Outcomes

By the end of this course, students will:

• Understand the challenges of cross-chain communication
• Know what separates Avalanche Warp Messaging from other cross-chain communication protocols
• Understand the ICM protocol layer and how it builds on AWM
• Set up ICM infrastructure (TeleporterMessenger, TeleporterRegistry, Relayer) on an L1
• Send and verify cross-chain messages using Console tools
• Understand relayer configuration, restrictions, and fee economics

For practical token bridging applications built on ICM, check out the ERC-20 Bridge and Native Token Bridge courses.