Secure and transferable e-tickets

The use of Information Technologies (IT) in the day-by-day operations is growing dramatically. Nowadays, it is possible to perform a lot of actions at home and there are not temporal restrictions. The electronic tickets are an example; people can buy a transport ticket or a movie ticket. In this sense, the smart-phones are a key element because users can buy the e-ticket from any place and can carry tickets while they are moving, and validate them in order to get access to the service . Moreover, the e-ticketing systems must offer the same properties of the paper tickets, i.e. they must be secure, anonymous and transferable. This solution uses cryptographic techniques in order to achieve the main security requirements for the system. Group signatures enable the users of a certain group to sign as a group member without need to reveal the real identity. This feature can give anonymity to the users of a system that could adopt this cryptographic primitive. However, the bad use of this group signature scheme should be penalized. To achieve so, revocable group signatures could be used and then a trusted authority (e.g. police or security forces) could have the right to revoke a determined group signature and adopt the considered actions. This way, if a ticket has been transferred and somebody misbehaved, a trusted authority could identify which is the part of the chain that misbehaved and identify him/her. The scheme has also been thought to be used in mobile devices in order to make it really practical either for users and entities of the system. In this direction, the use of the mobile devices as a smartcard in order to perform secure transactions is a trend that is more used recently. Near Field Communication is a communication technology which this solution could adopt to be used in a real system with mobile devices, and where the tickets could be stored in. However, the system can be deployed without the NFC technology. The e-ticketing system proposed can be used in different services, so that service providers can adapt the system in order to meet their requirements. The system provides to the users the same properties of the paper tickets. The tickets are anonymous and users can transfer them between them without the interaction of the ticket issuer or the provider. The method has been developed by researchers of two Spanish universitites, specialized in cryptographic systems. ICT providers specialized in the field of the electronic ticketing are beeing sought for a license agreement.