Persistent BitTorrent Trackers

Highlights

• On-chain reputation survives tracker failure (portable PKI)
• Hybrid ECDSA + BLS cuts signing cost ~10×
• Under 5% end-to-end transfer overhead

Abstract

Private BitTorrent trackers rely on centralized servers and self-reported statistics. We propose a decentralized alternative that stores reputation in smart contracts and uses cryptographic attestations: peers sign receipts for received pieces, and the tracker aggregates them via BLS signatures to update reputation. When trackers become unavailable, peers fall back to an authenticated distributed hash table, with stored reputation serving as public-key infrastructure. The design enables portable reputation across tracker failures and adds privacy protections — ephemeral session keys, zero-knowledge membership proofs, and homomorphic commitments for confidential reputation. Transfer receipts add less than 5% end-to-end overhead at typical piece sizes; a hybrid ECDSA + BLS scheme cuts client-side signing cost by an order of magnitude versus BLS alone.