Unlinkability
Each time a credential is requested by an ingress Gateway to prove that a client has purchased data to send through the Mixnet, the Requester's device produces a ticket. This is a rerandomised value that can be verified as legitimate (in that it was created by a valid root ticketbook) but is not linked to any other tickets, either previously generated or to be generated in the future. This also allows a single ticketbook to be split across multiple ingress Gateways or connections and incrementally spent over time.
The functionality included in the following code block examples were added to the nym-cli tool for illustrative purposes only: this is not necessarily how credentials will be accessed in the future.
The numbers used in this high level overview are for illustration only. The figures used in production may vary. Individual zkNym sizes are uniform across the Network.
❯ ./nym-cli ecash generate-ticket --credential-storage storage.db --provider 6qidVK21zpHD298jdDa1RRpbRozP29ENVyqcSbm6hQrG --ticket-index=3
TICKETBOOK DATA:
4Ys9pzUf9MPxX4s5RASyrRoY9fPk1a1kFuPBP2jm2L5PyUy535yPEfjHAfpUTC1Lf2d155TmjukvcDycQYfBSDfhEUJM4J3qPNfG3B5aQEEkefESZp3CM5AEnAu1AEyhpepbYw6BuXokiNcmaYtq3yJQbA4KicKP8FowoRzKHmXpJoUqY8wYQughGfdtXgr3rVaZmK21X51P1NL2UW1aCE512WWfy6P1LJHByWywT3qVw28Z83
attempting to generate payment for ticket 3...
PAYMENT FOR TICKET 3:
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 another ticket, to spend either when topping up after the previous one's data allowance has been used or with another Gateway. The ticket-index is the same: this is generated from the same aggregated credential as the one above.
❯ ./nym-cli ecash generate-ticket --credential-storage storage.db --provider 6qidVK21zpHD298jdDa1RRpbRozP29ENVyqcSbm6hQrG --ticket-index=3
TICKETBOOK DATA:
4Ys9pzUf9MPxX4s5RASyrRoY9fPk1a1kFuPBP2jm2L5PyUy535yPEfjHAfpUTC1Lf2d155TmjukvcDycQYfBSDfhEUJM4J3qPNfG3B5aQEEkefESZp3CM5AEnAu1AEyhpepbYw6BuXokiNcmaYtq3yJQbA4KicKP8FowoRzKHmXpJoUqY8wYQughGfdtXgr3rVaZmK21X51P1NL2UW1aCE512WWfy6P1LJHByWywT3qVw28Z83
attempting to generate payment for ticket 3...
PAYMENT FOR TICKET 3:
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 are both generated by the same underlying ticketbook and used in a way that they cannot be tied to each other. An ingress Gateway might (for instance) get 100 connection requests from 100 Nym clients, each validated with a ticket. It has no way of knowing whether these are all from the same single subscription, or 100 different ones.