System and method of verifying cryptographic postage evidencing using a fixed key set
June 28, 2019. Estimated Expiration Date is calculated based on simple USPTO term provisions. It does not account for terminal disclaimers, term adjustments, failure to pay maintenance fees, or other factors which might affect the term of a patent.Patent ReferencesCryptographic communication security for multiple domain networks Cryptographic communication security for single domain networks End-to-end encryption system and method of operation Method and apparatus for verifying postage Postage and mailing information applying system Postage and mailing information applying system System for detecting unaccounted for printing in a value printing system System for detecting unaccounted for printing in a value printing system Controlled use of cryptographic keys via generating station established control values Reliable document authentication system Inventors
AssigneeApplicationNo. 340592 filed on 06/28/1999US Classes:380/284, Using master key (e.g., key-encrypting-key)380/277, KEY MANAGEMENT380/278, Key distribution380/279, Key distribution center380/280, Control vector or tag380/281, Using master key (e.g., key-encrypting-key)380/282, By public key method380/283, User-to-user key distributed over data link (i.e., no center)380/285, By public key method705/401, Postage meter system705/405, Data protection705/410Specialized function performedExaminersPrimary: Swann, Tod R.Assistant: Callahan, Paul E. Attorney, Agent or FirmForeign Patent References
International ClassH04L 009/00AbstractA method for controlling keys used in the verification of encoded information generated by a transaction evidencing device and printed on a document comprises the steps of generating a plurality of random verifier master keys to obtain a set of verifier master keys consisting of a fixed number of keys; generating at least one pointer by applying a psuedorandom algorithm to data unique to the transaction evidencing device; calculating a plurality of verifier token keys to obtain a verifier token key set corresponding to the set of verifier master keys; encrypting the verifier token key set with a privacy key; and distributing the set verifier token keys and the privacy key to verifiers. The token keys are a function of the verifier master keys and a code valid for a limited time. The pointer algorithm is an appropriate symmetric key cryptographic algorithm and the code is function of a date dependent parameter. The master keys are distributed to postal and vendor data centers.Field of SearchKEY MANAGEMENTKey distribution Key distribution center Control vector or tag Using master key (e.g., key-encrypting-key) By public key method User-to-user key distributed over data link (i.e., no center) Using master key (e.g., key-encrypting-key) By public key method Postage meter system Data protection Specialized function performed With data comparing CODED RECORD SENSORS With scanning of record Identifying HAVING REVEALABLE CONCEALED INFORMATION, FRAUD PREVENTER OR DETECTOR, USE PREVENTER OR DETECTOR, OR IDENTIFIER Cryptogram (e.g., verification, tabular index) Identifier Personal Having dot pattern Having watermark CRYPTOGRAPHIC RECORD TEMPLATE CODE TRANSMITTERS Code recorders | |
