With the completion of the Pectra upgrade yesterday, let’s revisit Ethereum’s scaling roadmap: The Surge.Amid this wave of scaling, a key technology is quietly changing the game—PeerDAS (Data Availability Sampling).Why is PeerDAS needed?Ethereum is moving toward a rollup-centric multi-chain architecture. The main chain’s role is to store and verify data submitted by these rollups. However, as data volume explodes, the traditional method of downloading and verifying the entire dataset is becoming too slow and heavy.PeerDAS solves this by letting each node randomly verify only a small portion of the data. As long as everyone’s sampled chunks look valid, we can highly likely trust the entire dataset is available.What are the benefits?1. Light nodes can participate, lowering the barrier and increasing decentralization.2. Rollups can submit more data, relieving the main chain from becoming a bottleneck.3. Security relies on collective sampling, not a few super nodes.Instead of asking everyone to read the entire book, PeerDAS lets everyone sample a few pages.If all the sampled pages check out, we can trust the book is complete. That’s the idea behind PeerDAS.