HyBridge: A Hybrid Blockchain for PrivacyPreserving and Trustful Energy Transactions in InternetofThings Platforms In the current centralized IoT ecosystems, all financial transactions are routed through IoT platform providers. The security and privacy issues are inevitable with an untrusted or compromised IoT platform provider. To address these issues, we propose HyBridge, a hybrid blockchainbased billing and charging framework. In HyBridge, the IoT platform provider plays no proxy role, and IoT users can securely and efficiently share a credit with other users. The trustful endtoend functionality of blockchain helps us to provide accountability and reliability features in IoT transactions. Furthermore, with the blockchaindistributed consensus, we provide a creditsharing feature for IoT users in the energy and utility market. To provide this feature, we introduce a local block framework for service management in the creditsharing group. To preserve the IoT usersxe2x80x99 privacy and avoid any information leakage to the main blockchain, an interconnection position, called bridge, is introduced to isolate IoT usersxe2x80x99 peertopeer transactions and link the main blockchain to its subnetwork blockchain(s) in a hybrid model. To this end, a kanonymity protection is performed on the bridge. To evaluate the performance of the introduced hybrid blockchainbased billing and charging, we simulated the energy use case scenario using HyBridge. Our simulation results show that HyBridge could protect user privacy with an acceptable level of information loss and CPU and memory usage.

EVChain: A Blockchainbased Credit Sharing in Electric Vehicles Charging The Digital economy is based on confidence in its trustworthiness. Blockchain distributed consensus provides a reliable and trustful network for financial and nonfinancial transactions. Blockchainbased electric vehicles (EVs) charging applications benefit blockchain features to provide automated and verifiable services for EV charging market. Requirements for feasible charging operation and privacy concerns are challenging issues with blockchainbased EV charging approaches. To provide a feasible charging ability and preserve EV owneru0027s privacy, we introduce EVChain. The EVChain is a trustful and decentralized platform based on blockchain technology to share charging credits in the EV charging market. To share credits, the main blockchain in EVChain is connected to one or more subnetwork blockchains. We introduce an interconnection position to preserve EV ownersu0027 privacy with kanonymity protection. We simulate and evaluate the privacy protection it provides, based on an example EV charging scenario.