  Distributed Ledger Technologies (DLT) and Decentralized File Storages (DFS)
are becoming increasingly used to create common, decentralized and trustless
infrastructures where participants interact and collaborate in Peer-to-Peer
interactions. A prominent use case is represented by decentralized data
marketplaces, where users are consumers and providers at the same time, and
trustless interactions are required. However, data in DLTs and DFS are usually
unstructured and there are no efficient mechanisms to query a certain type of
data for the search in the market. In this paper, we propose the use of a
Distributed Hash Table (DHT) as a layer on top of DLTs where, once the data are
acquired and stored in the ledger, these can be searched through multiple
keyword based queries, thanks to the lookup functionalities offered by the DHT.
The DHT network is a hypercube overlay structure, organized for an efficient
processing of multiple keyword-based queries. We provide the architecture of
such solution for a decentralized data marketplace and an analysis based on a
simulation that proves the viability of the proposed approach.
