An apparatus, a method, and a computer program product of a wireless device are provided in which a first device identifier of a wireless device is provided. An allocation record is received that includes an expression used for discovery, a second device identifier, and at least one of a digital signature of a first server that delegates the expression or a digital signature of a second server that manages the expression. The allocation record is verified. An apparatus, a method, and a computer program product of a first server are provided in which a device identifier is received from a wireless device. An allocation record is generated that includes an expression used for discovery, the device identifier, and at least one of a digital signature of the first server or a digital signature of a second server that manages the expression. The allocation record is sent.