Sidechain
A sidechain is an independent blockchain designed to connect or interact with another blockchain while maintaining its own consensus and security system.
✦ Key Insight
Sidechains can provide faster transactions, lower fees, or specialised functionality. However, they should not automatically be treated as equivalent to Layer 2 rollups. A rollup may derive important security properties from Ethereum, while a sidechain typically relies on its own validators or consensus mechanism. This distinction matters when assessing security.
✕ Common Misconceptions
Calling every sidechain a Layer 2
Assuming Ethereum directly secures every connected chain
Ignoring bridge risk
Ignoring validator concentration
Assuming identical token symbols mean identical assets
Treating lower fees as proof of better security
Detailed Explanation
How It Works
A sidechain operates its own blockchain.
Users can move assets between the main blockchain and sidechain through bridges or related infrastructure.
The sidechain's validators process transactions according to its own consensus rules.
If the sidechain's security fails, the main blockchain does not necessarily reverse or protect transactions made there.
FAQs
Is a sidechain the same as a rollup?
No.
Does a sidechain have its own validators?
Typically yes.
Can sidechains interact with Ethereum?
Yes, usually through bridges or other interoperability systems.
In Practice
Dig Deeper
Layer 2
A Layer 2 is a scaling network built on top of a Layer 1 blockchain.
Rollup
A rollup is a Layer 2 scaling method that bundles many transactions together before posting them to a Layer 1.
Validator
A validator is a network participant in a Proof-of-Stake (PoS) blockchain that stakes cryptocurrency to propose, verify, and finalize new blocks of transactions, earning rewards for honest behavior and risking penalties (slashing) for misconduct.