L2 (Layer 2) is an extended solution with a separate execution layer (where the code runs, i.e. EVM) that inherits the security and decentralization of the network it runs on, i.e. L1, which in our case is Ether. This means that if L2 goes dark due to an error, infrastructure exploit or outage, the funds are safely protected by the L1's smart contract bridge. Funds can be retrieved based on the latest status snapshot submitted to the main network. A true L2 bridge is fully de-privileged and decentralized, so once a user deposits funds, there is always a guarantee. Some extension methods use different cryptographic proof mechanisms with different security and scalability tradeoffs.