Vault: Decentralized Storage Made Durable
This addresses data availability challenges in decentralized storage networks for users and developers, representing a novel method rather than incremental improvement.
The paper tackles the problem of Byzantine nodes targeting specific data blocks in decentralized storage networks by clustering within placement groups, which reduces rational nodes and weakens failure tolerance. The proposed Vault system uses a node-centric approach with sampling-based data placement and verifiable randomness to achieve scalable storage overhead and fault tolerance while maintaining availability.
Decentralized storage networks (DSNs) are storage systems powered by permissionless nodes. Data placement in DSNs must tolerate not only storage-device failures but also adversarial behavior that targets data availability. Byzantine nodes introduce unique challenges due to collusion and adaptive attacks. They can target specific data blocks by clustering within a block's placement group, reducing the number of rational nodes and weakening failure tolerance. In this work, we propose a global defense against Byzantine nodes across all placement groups. We introduce a node-centric approach that guarantees stable incentives for rational nodes regardless of the number of Byzantine nodes in their placement groups. Building on this approach, we design Vault, a DSN that uses sampling-based data placement with verifiable randomness. Compared with prior DSNs, this placement strategy allows Vault to scale simultaneously in storage volume, on-chain footprint, and Byzantine tolerance. Our preliminary results show that Vault achieves the desired availability with scalable storage overhead while maintaining scalable fault tolerance.