Research on the Application of E-CNY Boarding Code in Urban Rail Transit

［Objective］As in China E-CNY (hereinafter referred to as "digital currency") flourishes in all walks of life, the application scenarios of digital currency in urban rail transit are gradually enriched. Traditionally, digital currency is only used as a third-party payment application in rail transit, with functions similar to those of Alipay and WeChat. In order to further expand the application scenarios, it is proposed to use the digital currency APP (application software) to directly generate the digital currency boarding code, so that passengers can directly use the digital currency QR code to enter and exit the stations, making the digital currency travel scenarios more convenient. ［Method］The overall architecture and each module functions of the digital currency payment system in urban rail transit application scenarios are introduced; the digital currency QR code design schemes and key business processes are introduced. ［Result & Conclusion］Using digital currency soft wallet, and based on two asymmetric keys, the digital currency key and the subway key, the digital currency QR code is generated with reference to the Ministry of Transport QR code encoding format at the same time. With the digital currency key and the subway key as security guarantees, key business processes such as APP code request, gate code verification, and payment settlement are clarified.