1. A method comprising: given a unique identifier of a user, a password of the user, and a high-entropy random number, computing, by a computing device for each of a plurality of authentication devices, a high-entropy password based on the unique identifier, the password, the high-entropy random number, and an identifier that uniquely identifies the each of the plurality of authentication devices; and sending, by the computing device to each of the plurality of authentication devices, the computed high-entropy password corresponding to the each of the plurality of authentication devices; receiving, by the computing device from each of the plurality of authentication devices, an indication that the sent high-entropy password has been stored and that the user has been registered.