L2 Scalability Solution for Ethereum

This post surveys Layer 2 scalability solutions for Ethereum, which it presents as a response to network congestion and rising transaction costs, and it stresses that these solutions involve trade-offs and are not a single fix. It explains the Blockchain Trilemma, under which improving scalability tends to compromise security or decentralization. It describes Vitalik Buterin's view that layer 2 solutions process transactions off-chain, with a smart contract on the mainnet handling deposits, withdrawals and verification. The post covers state channels, which it says can perform thousands of transactions per second but require users to freeze funds in advance, and Plasma, which it says was created by Buterin and Joseph Poon and may require up to a week for withdrawals.