Definition
A sidechain is an independent blockchain that operates in parallel to a main blockchain while remaining linked to it through a technical connection. This connection is designed so that digital assets can be locked on the main chain and represented or used on the sidechain. The sidechain typically has its own rules, features, and security model, separate from the main chain. It functions as a distinct network but is conceptually part of a broader blockchain ecosystem.
Sidechains are often created to experiment with new features or to handle specific types of transactions without changing the main blockchain. They can use different consensus mechanisms, block sizes, or transaction formats than the main chain. The link between the main chain and the sidechain is usually managed by special protocols or entities that track and verify asset movements. This structure allows value to be transferred while keeping the two chains technically and operationally separate.
Context and Usage
In the context of cryptocurrency and blockchain, sidechains are viewed as a way to extend the capabilities of an existing network. A coin or token native to a main blockchain can be made usable on a sidechain by locking it on the main chain and issuing a corresponding representation on the sidechain. This lets the asset benefit from the sidechain’s specific design, such as faster blocks or different transaction rules. The original asset remains tied to the main chain, preserving its identity and total supply.
Sidechains are conceptually different from creating a completely unrelated blockchain because they are explicitly designed to interoperate with a particular main chain. They form part of a broader scaling and experimentation approach, where the main chain focuses on core security and settlement, and sidechains handle specialized tasks. The relationship between a main chain and its sidechains is defined by the rules that govern how assets are locked, released, and recognized across both chains. This makes sidechains a foundational concept for modular and multi-chain blockchain ecosystems.