Walking to Hide: Privacy Amplification via Random Message Exchanges in Network

Understand

The *shuffle model* is a powerful tool to amplify the privacy guarantees of the *local model* of differential privacy.

• In contrast to the fully decentralized manner of guaranteeing privacy in the local model, the shuffle model requires a central, trusted shuffler.
• To avoid this central shuffler, recent work of Liew et al.
• (2022) proposes shuffling locally randomized data in a decentralized manner, via random walks on the communication network constituted by the clients.