Tobacco products are an addictive commodity. According to the World Health Organization’s (WHO) latest statistics data, tobacco kills more than eight million people each year. In 2003, the WHO proposed the Framework Convention on Tobacco Control (FCTC) to provide an effective framework for the control of tobacco products to governments around the world. In the field of tobacco products, the hardest problem is how to prevent counterfeit tobacco products and smuggling. To solve the problems, we proposed a blockchain-based traceable and verifiable logistics system for tobacco products with global positioning system (GPS) and radio-frequency identification (RFID) Technologies. In this research, we provide an overview of system architecture, and also define the protocol and the smart contract in every phase that stores data into the blockchain center. We realized a decentralized database and authentication system that uses blockchain and smart contract technology; every protocol in every phase was designed to achieve the integrity of data and non-repudiation of message. Every tobacco product’s shipping record will be completed by scanning the RFID tag and retrieving the GPS with a mobile reader, where the record will be updated and validated in the blockchain center. In the end, the security and costs of the system were analyzed, and a comparison was made with the EU’s (European Commission) method. Our system is more flexible for transportation, more secure in the communication protocol, and more difficult to tamper and forge data. In general, the proposed scheme solved the problem of tobacco products counterfeiting and tracking issues.

Humans frequently need to construct a huge number of buildings for occupants in large cities to work or live in a highly developed civilization; people who live in the same building or same area are defined as a community. A thief stealing items, a burglary, fire hazards, flood hazards, earthquakes, emergency aid, abnormal gas leakage, strange behavior, falling in a building, fainting in a building, and other incidents all threaten the community’s safety. Therefore, we proposed a blockchain-based community safety security system that is combined with IoT devices. In the proposed scheme, we designed multiple phases to process the alarm triggered by IoT devices. IoT devices can be set up in two types areas: private and public areas. Both types of IoT devices’ alarms have different process flow for the response and records checking phase. All records are saved in the Blockchain Center to assure the data can be verified and cannot be forged. During the communication between sender and receiver, we implemented some security methods to prevent message repudiation, prevent transmission intercept, prevent replay attacks, and ensure data integrity. We also implemented a clarifying mechanism to ensure that all system participants can have confidence in the system’s processing methods. The proposed scheme can be used in communities to improve community safety and prevent unnecessary conflicts.

The wide spread of WLAN and the popularity of mobile devices increases the frequency of data transmission among mobile users. How to provide a secure and convenient protocol for data transmission is important. In this paper we propose a location-dependent approach is proposed for mobile information system. The mobile client transmits a target latitude/longitude coordinate for data encryption to information server. Then, the server encrypts the message and sends the ciphertext back to the mobile client. The client can only decrypt the ciphertext when the coordinate acquired form GPS receiver matches with the target coordinate. According to our discussion, the approach can meet the confidentiality, authentication, simplicity, and practicability of security issues. As a result, the proposed approach can meet the demands of mobile information system in the future.

Recently, private security services have become increasingly needed by the public. The proposed scheme involves blockchain technology with a smart contract. When a private security company signs a contract with a client, they install an Internet of Things (IoTs) device in the client’s house and connect it with the IoT main controller; then, the IoT main controller connects to the security control center (SCC). Once there is an event triggered (e.g., a break-in or fire incident) by the IoTs device, the controller sends a message to the SCC. The SCC allocates a security guard (SG) to the incident scene immediately. After the task is accomplished, the SG sends a message to the SCC. All of these record the messages and events chained in the blockchain center. The proposed scheme makes security event records have the following characteristics: authenticated, traceable, and integral. The proposed scheme is proved by a security analysis with mutual authentication, traceability, integrity, and non-repudiation. The known attacks (e.g., man-in-the-middle attack, replay attack, forgery attack) are avoided by message encryption and a signing mechanism. Threat models in the communication phase can also be avoided. Finally, computation cost, communication performance, and comparison with related works are also discussed to prove its applicability. We also provide an arbitration mechanism, so that the proposed scheme can reduce disputes between private security companies and the client.