Sidechain
A sidechain is an independent blockchain connected to a main chain by a two-way bridge: lock coins on one side, mint equivalents on the other. Unlike a rol
A sidechain is an independent blockchain connected to a main chain by a two-way bridge: lock coins on one side, mint equivalents on the other. Unlike a rollup, a sidechain has its own validators and security — the main chain doesn’t verify its blocks.
Why it matters
“Layer 2” gets slapped on sidechains in marketing, but the security model is completely different: a rollup inherits Ethereum’s security; a sidechain is only as safe as its own (usually much smaller) validator set. Polygon PoS is the famous example — fast and cheap, secured by its own ~100 validators, not by Ethereum.
Related terms
layer 2 · bridge ·
blockchain