Patent attributes
Systems and methods are provided for computing a secret shared with a portable electronic device and service entity. The service entity has a public key G and a private key g. A message comprising the public key G is broadcast to the portable electronic device. A public key B of the portable electronic device is obtained from a manufacturing server and used together with the private key g to compute the shared secret. The portable electronic device receives the broadcast message and computes the shared secret as a function of the public key G and the portable electronic device's private key b. The shared secret can be used to establish a trusted relationship between the portable electronic device and the service entity, to activate a service on the portable electronic device, and to generate certificates.