Abstract: A mass storage drive removably supports a mass storage element and includes a data head having an output for reading tracks of main data elements. The data head, which can be an optical head, is movable in a predetermined auxiliary path relative to the substrate for scanning a unique machine-readable serial identifier in auxiliary data containing at least 200 bits of information in one or more tracks being exclusive of main data tracks. The mass storage drive includes a head circuit connected to the data head output and having a main amplifier with an output for signaling main data elements in response to the data head, the circuit having a separate auxiliary put for signaling the auxiliary data elements in response to the data head output. The head circuit can include an auxiliary amplifier for driving the auxiliary output.

Abstract: A method is provided for inhibiting the generation of digital tokens in an open metering system that includes a host processor and a vault. The method includes the steps of generating in the host processor a first digital token request that corresponds to a first destination identifier and a first postage amount; determining in the host processor if one of the first destination identifier and the first postage amount is different than a prior destination identifier and a prior postage mount, respectively, that correspond to an immediately preceding digital token request; sending the first digital token request to the vault when the first destination identifier and the first postage amount are different than the prior destination identifier and the prior postage amount, respectively; and rejecting the first digital token request when the first destination identifier and the first postage amount are the same as the prior destination identifier and the prior postage amount, respectively.