All terms
An independent chain connected to another by a bridge, with its own security.
A sidechain runs its own consensus and validator set. It connects to a main chain through a bridge but does not inherit its security.
This is the crucial difference from a rollup. If a sidechain's validators collude, the main chain cannot help you.
Polygon PoS began as a sidechain. That is why L2BEAT categorizes it differently from true rollups.
That a sidechain is a layer 2. A rollup settles to the base chain; a sidechain has its own validators and its own security, connected by a bridge. If the sidechain fails, the base chain cannot help you, and the bridge is usually the weakest part.
Common questions
Is a sidechain a layer 2?
Why use a sidechain at all?
Where this comes up on the site
The guides that actually use this word, rather than a list of everything we have written.
Where to go next
More technology terms
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