An Offline Authenticate Technology Research In Public Transport Payment System Using QR Code

Public transportation becomes more and more popular.With the application of information technology,many city vehicles support public transportation card.Public transportation card is one kind of radio frequency identification device.It uses offline transaction method.Public transportation card trades speed and safety,effectively solves change-making problem.However,there is a popular supposition that being able to pay with mobiles is easier than using card.Recently,with the rapid development of mobile communication technology,people want more choices.They want to use QR Code payment while using public transport services.However,QR Code lack of secure mechanism to satisfied secure requirement in payment.Online transaction has been generally accepted in mobile payment.In this mode,the QR Code data is validated real time through an asynchronous server.It is not a good idea to use this mode on public transport because network communication is frequency blocked during bus driving.In this paper,an offline payment system design and implementation will be proposed.The author uses cryptological technique to solve trusted transaction problem while using QR Code.First of all,the paper introduced the relevant technical knowledge,such as QR Code,digital signatures,digital digest,etc.Secondly,researching the risk of offline QR Code transaction.Thirdly,the paper provides a solution that using the user credential and message authentication to generate QR Code.It is a transaction authentication mechanism which ensures the validity,integrity and non-repudiation of transaction.In order to provide this functionality,the paper design architectures and data structure and application flows,including QR Code encoding,QR Code decoding,key derivation function,MAC.And then,the detail design and implement to the modules was given.After coding and testing,the system successfully achieves the desired goals.The whole point of this system is to let you using QR Code as single ticket,which you can create in APP and pay with your mobile device in offline environment.