What is a Layer 2 Network?
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A Layer 2 (L2) is a secondary network built on top of a Layer 1 (L1) blockchain. It processes transactions off the main chain — or batches them — while ultimately settling back to the L1, inheriting its security and finality guarantees.
Why Layer 2s exist
Every L1 has a throughput ceiling. As demand grows, users bid for limited block space, driving up network costs. Layer 2s address this by executing transactions in a higher-capacity environment and posting only compressed proofs or summaries to the L1.
The result: lower fees and faster confirmations for users, without sacrificing the decentralization of the underlying chain.
How they work
The most common L2 architecture is the rollup, which comes in two variants:
- Optimistic rollups assume transactions are valid by default and only run fraud proofs if a challenge is raised during a dispute window.
- ZK (zero-knowledge) rollups generate a cryptographic validity proof for each batch, providing immediate finality once the proof is verified on L1.
Both types aggregate many user transactions into a single L1 transaction — hence the name "rollup."
Using a Layer 2
To interact with an L2, you first bridge funds from the L1 to the L2 network. Once bridged, you can swap, provide liquidity, and transact at the L2's lower fee structure. Withdrawing back to L1 may involve a delay, depending on the rollup type.
Risks
Layer 2 networks may still be in beta. A critical bug in the L2's contracts or sequencer can affect all protocols deployed on it — including the CenturionDEX Protocol — independent of their own security. Before depositing significant value, evaluate:
- The rollup's upgrade mechanism and multisig controls.
- Whether fraud proofs or validity proofs are fully operational.
- The maturity of the bridge contracts.
A total loss of funds is possible if a severe L2 vulnerability is exploited.