Subnet (Avalanche L1)

Avalanche lets projects launch their own chains with their own rules, virtual machine, fee token and validator set, while still connecting to the wider network for messaging and discovery. These were long called subnets, short for subnetworks, and were rebranded as Avalanche L1s after the Avalanche9000 upgrade in late 2024, which also made them cheaper to run by dropping the requirement to stake on the primary network.

Games, financial institutions and companies use the model when they want dedicated blockspace, predictable fees or permissioned access, for example requiring validators or users to pass identity checks. Interchain messaging lets these chains exchange tokens and data with each other.

Each subnet is secured only by its own validators, so a small set provides far less security than the main network; it is closer to an app-chain than to a rollup. Liquidity and users are fragmented across chains. The word also has other meanings: Bittensor calls its specialised AI markets subnets, which work quite differently.