Sidechain
Share post
In Brief
A sidechain is an independent blockchain that runs alongside a main chain and connects to it through a two-way bridge, letting assets move between the two while the sidechain keeps its own rules, consensus, and security.
What Is a Sidechain?
A sidechain is an independent blockchain that runs in parallel with a main chain — such as Bitcoin or Ethereum — and connects to it through a two-way bridge. Assets can move from the main chain to the sidechain and back, while the sidechain sets its own rules: its own consensus mechanism, block times, fees, and features.
The appeal is freedom. A sidechain can be faster and cheaper than its parent, or experiment with features the main chain doesn't offer, without asking the main chain to change.
How a Sidechain Works
You send assets to a bridge contract or federation on the main chain, where they're locked.
Equivalent assets are minted or released on the sidechain for you to use.
Transactions on the sidechain follow its own consensus and fee rules, independent of the main chain.
To exit, you return the sidechain assets and the bridge unlocks the originals on the main chain.
Sidechain vs. Layer 2
The crucial difference is security. A Layer 2 rollup posts its data to the main chain and inherits its security — the main chain can catch a cheating rollup. A sidechain is responsible for itself: if its validators are compromised or its bridge fails, the main chain offers no protection. "Cheaper and faster" is real, but it's paid for with a separate, usually smaller, security budget.
Sidechains and Trust Wallet
Trust Wallet supports major sidechains and Layer 2 networks among its 100+ blockchains, with in-app swaps and a dApp browser for using apps wherever they live. Whichever chain you transact on, your keys stay yours — and the Security Scanner reviews what you sign.