Skip to Main content Skip to Navigation
Conference papers

Secure Outsourcing of Multi-Armed Bandits

Abstract : We consider the problem of cumulative reward maximization in multi-armed bandits. We address the security concerns that occur when data and computations are outsourced to an honest-but-curious cloud i.e., that executes tasks dutifully, but tries to gain as much information as possible. We consider situations where data used in bandit algorithms is sensitive and has to be protected e.g., commercial or personal data. We rely on cryptographic schemes and propose UCB-DS, a distributed and secure protocol based on the UCB algorithm. We prove that UCB-DS computes the same cumulative reward as UCB while satisfying desirable security properties. In particular, cloud nodes cannot learn the cumulative reward or the sum of rewards for more than one arm. Moreover, by analyzing messages exchanged among cloud nodes, an external observer cannot learn the cumulative reward or the sum of rewards produced by some arm. We show that the overhead due to cryptographic primitives is linear in the size of the input. Our implementation confirms the linear-time behavior and the practical feasibility of our protocol, on both synthetic and real-world data.
Complete list of metadatas
Contributor : Radu Ciucanu <>
Submitted on : Wednesday, September 30, 2020 - 8:52:57 AM
Last modification on : Wednesday, October 14, 2020 - 3:58:49 AM


  • HAL Id : hal-02953292, version 1


Radu Ciucanu, Pascal Lafourcade, Marius Lombard-Platet, Marta Soare. Secure Outsourcing of Multi-Armed Bandits. 19th IEEE International Conference on Trust, Security and Privacy in Computing and Communications (TrustCom 2020). Accepté, à paraître., Dec 2020, Guangzhou, China. ⟨hal-02953292⟩



Record views