trafficBCDB: A Traffic-Aware Blockchain Database for Verifiable Transportation Data Sharing

Abstract

Transportation records cross organizations with different urgency, privacy, and audit requirements. Encrypted databases support local storage and queries, while ledgers can preserve commitments that other organizations verify. This paper presents trafficBCDB, which binds an ordered record batch to its policy and ledger-selection context and returns authenticated range proofs with ledger receipts. The implementation uses threshold proxy re-encryption, three SQLite replicas, and separate four-node Geth Clique and Tendermint networks. The routing study compares nine policies using controlled workloads and actual New York City taxi pickup records, with shared observations and 20 paired random seeds. On the generated workload, trafficBCDB reaches 98.184% joint constraint satisfaction at 303.4 ms modeled latency, compared with 96.803% for a calibrated fixed policy. A constrained optimizer reaches 98.191% at 300.9 ms. On the citywide taxi replay, trafficBCDB reaches 26.64% under the stated synthetic ledger and policy assumptions. Separate native experiments measure inclusion, ledger-specific acceptance, encrypted storage, proof verification, and decryption. The results establish a concrete accountable data path and expose its routing, confidentiality, and availability limits.