# US 2019/0172064 A1 · Systems and methods for validating transmissions over communication channels > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0172064 A1 - Document ID: US20190172064A1 - Status: Published application - Kind: A1 - Application number: 16/312,871 - Filed: 2016-07-01 - Published: 2019-06-06 - Earliest claimed: 2016-07-01 - Assignees: American Express Travel Related Services Company, Inc. - Applicants: American Express Travel Related Services Company, Inc. - Inventors: Carlos Eduardo Oliveira do Valle Silvestre; Jonathan Ward Lupton - Web page: https://patentgrep.com/patent/US20190172064A1 ## CPC - G06Q 20/401: {Transaction verification} - G06Q 20/3278: {RFID or NFC payments by means of M-devices} - G06Q 20/3823: {combining multiple encryption tools for a transaction} - H04L 9/3242: {involving keyed hash functions, e.g. message authentication codes [MACs], CBC-MAC or HMAC} - G06Q: INFORMATION AND COMMUNICATION TECHNOLOGY [ICT] SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES; SYSTEMS OR METHODS SPECIALLY ADAPTED FOR ADMINISTRATIVE, COMMERCIAL, FINANCIAL, MANAGERIAL OR SUPERVISORY PURPOSES, NOT OTHERWISE PROVIDED FOR - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract An authentication system may receive an authentication MAC, an integrity MAC, and data transmitted from a payment application and a payment terminal. A local integrity MAC may be generated using the data as an input to a first cryptographic operation. The system may compare the local integrity MAC to the received integrity MAC to authenticate the received integrity MAC. A local authentication MAC may be generated using a second cryptographic operation and compare the local authentication MAC to the received authentication MAC. The system may authenticate the payment application in response to a successful authentication of at least one of the received authentication MAC or the received integrity MAC. ## Claims ### Claim at position 1 -20. (canceled) ### Claim 21 A method comprising: receiving, by a processor, an authentication MAC, an integrity MAC, and transaction data transmitted from a payment application and a payment terminal, wherein the integrity MAC is generated from the transaction data using a cryptography key stored in the payment application; generating, by the processor, a local integrity MAC using the transaction data as an input to a first cryptographic operation using a copy of the cryptography key accessible by the processor; comparing, by the processor, the local integrity MAC to the received integrity MAC to authenticate the received integrity MAC in response to the local integrity MAC matching the received integrity MAC; generating, by the processor, a local authentication MAC using a second cryptographic operation; comparing, by the processor, the local authentication MAC to the received authentication MAC to authenticate the received authentication MAC in response to the local authentication MAC matching the received authentication MAC; and authenticating, by the processor, the payment application in response to a successful authentication of at least one of the received authentication MAC or the received integrity MAC. ### Claim 22 (depends on 1) The method of claim 1, further comprising retrieving, by the processor, an input to the second cryptographic operation, wherein the input to the second cryptographic operation is generated independently from the transaction data received by the processor from the payment application and the payment terminal. ### Claim 23 (depends on 2) The method of claim 2, wherein the input to the second cryptographic operation comprises data replicable at the issuer host. ### Claim 24 (depends on 1) The method of claim 1, wherein the first cryptographic operation is the same as the second cryptographic operation. ### Claim 25 (depends on 1) The method of claim 1, wherein the first cryptographic operation comprises an authentication encryption mode. ### Claim 26 (depends on 1) The method of claim 1, further comprising approving a transaction in response to the successful authentication of at least one of the authentication MAC or the integrity MAC. ### Claim 27 (depends on 1) The method of claim 1, wherein the authentication MAC and the integrity MAC are transmitted from the payment application, to the payment terminal, through a payment network, and to the processor. ### Claim 28 A computer-based system comprising: a processor; a tangible, non-transitory memory configured to communicate with the processor, the tangible, non-transitory memory having instructions stored thereon that, in response to execution by the processor, cause the processor to perform operations comprising: receiving, by the processor, an authentication MAC, an integrity MAC, and transaction data transmitted from a payment application and a payment terminal, wherein the integrity MAC is generated from the transaction data using a cryptography key stored in the payment application; generating, by the processor, a local integrity MAC using the transaction data as an input to a first cryptographic operation using a copy of the cryptography key accessible by the processor; comparing, by the processor, the local integrity MAC to the received integrity MAC to authenticate the received integrity MAC in response to the local integrity MAC matching the received integrity MAC; generating, by the processor, a local authentication MAC using a second cryptographic operation; comparing, by the processor, the local authentication MAC to the received authentication MAC to authenticate the received authentication MAC in response to the local authentication MAC matching the received authentication MAC; and authenticating, by the processor, the payment application in response to a successful authentication of at least one of the received authentication MAC or the received integrity MAC. ### Claim 29 (depends on 8) The computer-based system of claim 8, further comprising retrieving, by the processor, an input to the second cryptographic operation, wherein the input to the second cryptographic operation is generated independently from the transaction data received by the processor from the payment application and the payment terminal. ### Claim 30 (depends on 9) The computer-based system of claim 9, wherein the input to the second cryptographic operation comprises data replicable at the issuer host. ### Claim 31 (depends on 8) The computer-based system of claim 8, wherein the first cryptographic operation is the same as the second cryptographic operation. ### Claim 32 (depends on 8) The computer-based system of claim 8, wherein the first cryptographic operation comprises an authentication encryption mode. ### Claim 33 (depends on 8) The computer-based system of claim 8, further comprising approving a transaction in response to the successful authentication of at least one of the authentication MAC or the integrity MAC. ### Claim 34 (depends on 8) The computer-based system of claim 8, wherein the authentication MAC, the integrity MAC, and the transaction data are transmitted from the payment application, to the payment terminal, through a payment network, and to the processor. ### Claim 35 An article of manufacture including a non-transitory, tangible computer readable storage medium having instructions stored thereon that, in response to execution by a processor, cause the processor to perform operations comprising: receiving, by the processor, an authentication MAC, an integrity MAC, and transaction data transmitted from a payment application and a payment terminal, wherein the integrity MAC is generated from the transaction data using a cryptography key stored in the payment application; generating, by the processor, a local integrity MAC using the transaction data as an input to a first cryptographic operation using a copy of the cryptography key accessible by the processor; comparing, by the processor, the local integrity MAC to the received integrity MAC to authenticate the received integrity MAC in response to the local integrity MAC matching the received integrity MAC; generating, by the processor, a local authentication MAC using a second cryptographic operation; comparing, by the processor, the local authentication MAC to the received authentication MAC to authenticate the received authentication MAC in response to the local authentication MAC matching the received authentication MAC; and authenticating, by the processor, the payment application in response to a successful authentication of at least one of the received authentication MAC or the received integrity MAC. ### Claim 36 (depends on 15) The article of claim 15, further comprising retrieving, by the processor, an input to the second cryptographic operation, wherein the input to the second cryptographic operation is generated independently from the transaction data received by the processor from the payment application and the payment terminal. ### Claim 37 (depends on 16) The article of claim 16, wherein the input to the second cryptographic operation may comprise data replicable at the issuer host. ### Claim 38 (depends on 15) The article of claim 15, wherein the first cryptographic operation is the same as the second cryptographic operation. ### Claim 39 (depends on 15) The article of claim 15, wherein the first cryptographic operation comprises an authentication encryption mode. ### Claim 40 (depends on 15) The article of claim 15, further comprising approving a transaction in response to the successful authentication of at least one of the authentication MAC or the integrity MAC.