disclosed is a multi - purpose secure and anonymous payment system based on a variety of cryptographic confidentiality , authentication , and privacy methods . users pay anonymously over the internet using their mobile phones supported by the secure sim card . the sim cards do not reveal any personal payment information that is not directly necessary for the transaction to either the merchant or the bank . the system allows configuration of different cryptographic methods or hardware components to allow proper balancing of any specific implementation while maintaining strong security and privacy . it is resilient to connection breakdowns and allows users and merchants to recover from such disruptions without maintaining complex transaction states on the sim card and without financial losses to any of the parties . the system and protocols can also be configured for electronic cash payments with smart cards or software agents on the internet or at conventional merchant sale terminals .