An Overview of Layer 3s

Layer 2 (L2) scaling solutions such as rollups offload computations and batch transactions to be posted as raw data on Layer 1s (L1s). It mitigates the scalability issues faced by Ethereum, such as high transaction costs and limited throughput, be it with fraud proofs through optimistic rollups (ORUs) or validity proofs through zk-rollups (ZKRs). 

Beyond L2s, there have been developments on Layer 3s (L3s), layers that could compound the scaling benefits of L2s and provide higher levels of customizability and optimization while inheriting security from L1s with the use of recursive proofs.