This is a breakdown of how Avalanche is structured: its consensus design, Subnet model, and internal chain roles. If you're working on-chain infra or considering Avalanche for deployment, start here.

About the Core Technology and Infrastructure

The way Avalanche is built is key to its performance and what it can do. This part of our discussion looks at its transaction confirmation system, its method for creating custom blockchains called Subnets, the roles of its three main internal chains, and how it keeps the network secure.

How Avalanche Achieves Fast Transactions

Avalanche uses a distinct approach to agree on transactions, which allows it to be fast and handle many users. At its heart are two related methods: the Avalanche consensus protocol and the Snowman consensus protocol. 

The main idea behind Avalanche consensus, primarily used by its X-Chain, is a rapid, iterative polling process. When a transaction appears, validators quickly ask a small, random subset of other validators for their opinion. 

If enough in that sample agree, the validator leans towards that decision. This process repeats many times in quick succession, allowing the network to quickly converge on a decision that becomes irreversible.

The Snowman consensus protocol is an adaptation of this, optimized for situations that require a strict, linear order of transactions, which is essential for smart contracts. You'll find Snowman securing the C-Chain (for smart contracts) and the P-Chain (for platform-level operations). This overall consensus mechanism is designed to provide significant speed and scalability. 

Transactions can often achieve finality in under two seconds, meaning they are confirmed and irreversible. The network is also built to handle a high volume of transactions per second (TPS), potentially thousands, especially as specialized tasks are offloaded to Subnets. 

The system's security comes from this repeated sampling and the statistical difficulty an attacker would face trying to sway the outcome without controlling an improbable amount Eof network power.

Subnets are Custom Blockchains on Avalanche

A core innovation within Avalanche is the concept of Subnets, or Subnetworks. These allow for the creation of many independent, yet interconnected, blockchains. Essentially, a Subnet is a dedicated blockchain built for a specific application or a set of applications. 

This design offers several advantages. It greatly helps with scalability because traffic for one application on its own Subnet doesn’t slow down other applications on different Subnets or the main Avalanche network.

Subnets also offer extensive customization. Developers can define their own rules for their blockchain, such as who can participate (allowing for private or permissioned chains suitable for enterprises), how transaction fees are structured (they can even use a custom token for gas fees), and the underlying virtual machine that executes transactions. 

While Subnets operate with a degree of independence, they are anchored to the main Avalanche network. Validators who secure a Subnet are also required to validate Avalanche's Primary Network by staking AVAX, contributing to overall security. 

Launching a Subnet involves defining its parameters and having a group of validators, along with a nominal AVAX fee for registration. We've seen Subnets used effectively in various areas: gaming projects like DeFi Kingdoms and Beam use them for tailored, high-performance environments; DeFi applications like Dexalot have launched Subnets for specialized exchange functions; and enterprises are exploring them for solutions requiring specific compliance and control.

The Main Avalanche Network

The Avalanche Primary Network itself is composed of three specialized blockchains that work together: the X-Chain, P-Chain, and C-Chain. Each has a distinct role.

The Exchange Chain (X-Chain) is used for creating, managing, and trading digital assets, including Avalanche's native token, AVAX, as well as other custom tokens and NFTs. It utilizes the Avalanche consensus protocol for fast asset transfers.

The Platform Chain (P-Chain) handles metadata and network coordination. Its responsibilities include managing the list of active validators, overseeing staking operations, and enabling the creation and tracking of new Subnets and other blockchains within the ecosystem.

The Contract Chain (C-Chain) is dedicated to smart contracts and is where most decentralized applications (dApps) like those in DeFi and NFT marketplaces are deployed. 

A critical feature of the C-Chain is its EVM compatibility. It means it can run smart contracts written for Ethereum, allowing developers to use familiar tools and programming languages like Solidity. This compatibility has been a significant factor in attracting developers to build on Avalanche.

Mapping What’s Being Built

Avalanche’s infrastructure supports a range of active deployments. Projects are using Subnets for isolated execution environments, optimized performance, and regulatory alignment. The core chains continue to handle asset transfers, validator management, and smart contract execution at scale.

To get a broader view of how it all connects, which projects are live, what Subnets are in play, and where the network is expanding, explore our Avalanche Ecosystem Map