  Blockchains have become the catalyst for a growing movement to create a more
decentralized Internet. A fundamental operation of applications in a
decentralized Internet is data storage and retrieval. As today's blockchains
are limited in their storage functionalities, in recent years a number of
peer-to-peer data storage networks have emerged based on the Kademlia
distributed hash table protocol. However, existing Kademlia implementations are
not efficient enough to support fast data storage and retrieval operations
necessary for (decentralized) Web applications. In this paper, we present
Kadabra, a decentralized protocol for computing the routing table entries in
Kademlia to accelerate lookups. Kadabra is motivated by the multi-armed bandit
problem, and can automatically adapt to heterogeneity and dynamism in the
network. Experimental results show Kadabra achieving between 15-50% lower
lookup latencies compared to state-of-the-art baselines.
