**2. Background**

Given the growing concern around the trading activities of counterfeit products, anti-counterfeiting solutions have been developed and implemented in the supply chain systems of different industries.

### *Related Work of Anti-Counterfeiting and Traceability Systems*

The starting point, such as in [5], is always digitalizing the multi-node supply chain system under which the supply chain network will at least be operating with a Point-of-Sale (POS) system integrated with the states of a data storage system updated at different nodes along the supply chain. Wireless communication technologies, such as Radiofrequency Identification (RFID) or near-field communication (NFC), which is a subset of RFID, powering the Internet of Things (IoT) are mostly the existing solutions that the centralized architectures are currently based on. The tags with wireless communication capabilities are packaged on the packets of goods or the product itself for identification, anti-counterfeiting, and traceability purposes.

The RFID-based solutions in [6,7] and NFC-based solutions in [8,9] both require dedicated applications or authentication servers to integrate with these tags so as to perform writing, reading, and validating features on the data stored in these tags with the product identifier (PID). Its metadata are also stored in a database system of applications for the purpose of validation at later stage to respond to any potential counterfeiting attack at different supply chain nodes. The work in [10] utilized simple barcode technology, such as QR code, to retrieve the product identifiers by scanning the products and querying corresponding records throughout the dedicated backend database systems to retrieve metadata of specific PIDs so as to prove the authenticity with the PIDs validated and detailed product data retrieved, such as in [11] where this method was implemented for drug anti-counterfeiting.

For instance, with the wider adoption of these wireless communication and barcode technologies, the concept of RFID-enabled track-and-trace anti-counterfeiting was also proposed in [12,13], respectively, to combat counterfeiting activities. RFID-enabled anticounterfeiting approaches are further analyzed and compared with potential implementation issues in [7,14]. The *EPCglobal* traceable system to support anti-counterfeiting is further extended in [15,16]. The authors of [17] suggested the use of a Wireless Sensor Network (WSN) and geospatial technologies, such as Geographic Information System (GIS), Global Positioning System (GPS), and Remote Sensing (RS), for mobile assets-tracking operations; these are among the technologies that have been applied in product traceability systems.

Nevertheless, many of the existing implementations for product anti-counterfeiting in the supply chain industry are indeed built with centralized architecture relying on a trusted server, database, and applications. These implementations are solely controlled and managed by the manufacturers or suppliers of the products, for coordinating and managing product authentication with participation contributed from different nodes along the supply chain of different industries.

### **3. Decentralizing with the Blockchain Technology**

In this section, following the advantages introduced by the blockchain technology, the modern core blockchain concepts including those of blockchain 1.0 and blockchain 2.0 are explained. A variety of current blockchain implementations applied to different types of supply chain industries is also mentioned. The reasons why developing decentralized solutions based on existing systems of centralized architecture is a pragmatic way going

forward to improve the challenging product counterfeiting in the wider supply chain industry are also given.
