Mastering Ethereum, 2nd Edition

Chapter 16. Scaling Ethereum

Ethereum is one of the most powerful and widely used blockchain platforms, but as we’ve seen time and again, success comes with growing pains. Ethereum has become so popular that its base layer is having trouble keeping up, gas fees often get so high that transactions become too expensive, and the system is becoming weighed down by all the data it has to handle. While Ethereum developers have been rolling out upgrades like EIP-1559 (described in Chapter 6), The Merge (the 2022 hard fork that changed the consensus protocol from PoW to PoS), and EIP-4844 (proto-danksharding, described later in this chapter), the fundamental constraints of L1 remain a bottleneck for mass adoption. These improvements help, but they don’t eliminate the need for additional scaling solutions like L2 rollups.

Note

L2 rollups are scaling solutions that process transactions off chain and then post a summary (such as a proof or data batch) to Ethereum’s Layer 1. This reduces congestion and fees while still relying on Ethereum for security. There are two main types: optimistic rollups (assume valid, challenge if wrong) and zero-knowledge rollups (prove correctness with cryptography). Ethereum essentially becomes a settlement layer, meaning its main role shifts toward verifying proofs, ensuring data availability, and providing ultimate security guarantees for L2 transactions. We will explore rollups in detail in the second part of this chapter.

The Problems of Ethereum’s Layer ...