# Secure and Privacy-Protected Bioinformation Implementation in Air Passenger Transport Based on DLT
## 1 Introduction  
The International Air Transport Association (IATA) has proposed the One ID concept, which aims to offer passengers a consistent, seamless experience across airlines, airports, and governments [1]. According to this concept, the use of bioinformatic identification technology can streamline the user's airport processes, increase operational efficiency, and reduce the need for human intervention. As a product of the fusion of biometrics and information technology, bioinformatic identification technology has demonstrated excellent application potential in a wide range of fields. Its basic principle is to identify and verify the identity of an individual by capturing and analyzing biologically unique physiological or behavioral characteristics. This field encompasses a wide range of biometric traits including, but not limited to, fingerprints, irises, faces, voices, and genetic sequences. Biometrics has important applications in the fields of security, healthcare, finance, and social management, providing highly accurate and unforgeable solutions for individual identification [2]. One of the most popular and technologically mature methods is facial recognition. Since facial recognition is a non-invasive method of bioinformatic identification technology, the personbeing captured does not need to be in direct contact with the sensor, making it simple and convenient to capture information [3]. For technology collectors, the camera can do the job without special equipment or a collection process. Therefore, facial recognition is applied in this research as a bioinformation recognition method. Multiple parties participate in air passenger transport, including airlines, airports, and border control authorities. Each of these parties operates at different stages and locations to serve passengers' trips. To ensure the safe and efficient delivery of aviation services and regulations, effective coordination and collaboration among these parties are required. Facial information and other personally identifiable information that needs to be shared by various parties is highly private. The sharing of such information is essential for coordination and cooperation by these relevant participants. While sharing information among a small number of parties in a system may not be complicated, the complexity of managing data privacy and trust among different parties increases as the number of participants grows. Therefore, there is a need for a solution that can facilitate effective information sharing among multiple parties while maintaining data privacy and trust. Distributed Ledger Technology (DLT) has the potential to address these challenges by providing a secure and transparent platform for data sharing. A DLT system is a type of distributed system that enables independent entities to establish consensus around a shared ledger without relying on a central coordinator [4]. DLT can assist in sharing and synchronizing data across a distributed computer network [5]. Since air passenger transportation involves multiple parties, each group is responsible for different parts of the transportation process. Therefore, DLT with decentralized characteristics is suitable for application in the air passenger information transmission process. Its central control could eliminate single points of failure. In addition, DLT can grant participants different authorizations to distinguish the information obtained and perform different operations by participants, which is called permissioned DLT. Permissioned DLT allows transparent access to data for related parties while ensuring that data are stored securely and accurately using cryptography to prevent access by unauthorized parties [6]. The transparency and security provided by DLT can help manage the accountability of different stakeholders and improve the protection of sensitive passenger data. Based on this, this study adopts DLT as the framework for enabling information sharing and transmission.