Introduction Efficient management of authenticated data has emerged as a critical research challenge in the blockchain space, particularly given the recent rise of parallel EVM. This post reviews Merkle Patricia Trie-based authenticated storage (currently used in Ethereum)[^12] and analyzes some of its potential alternatives. A typical blockchain manages its state via a two-layered architecture in which an authenticated data structure (ADS) is built on top of a backend database. 00_two_layered_blockchain Figure. Typical two-layered blockchain design. The ADS guarantees data integrity and is typically built using a Merkle tree-like structure. It also provides a mechanism to verify the presence of specific data within the state. Nodes in the ADS are usually connected via hashes, and each node is stored in the underlying database: leaf nodes hold actual key-value pairs, while internal nodes contain metadata (e.g., hashes) about their children.