# US 2014/0196109 A1 · Method and device for the authentication of at least two agricultural devices coupled via a data bus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0196109 A1 - Document ID: US20140196109A1 - Status: Published application - Kind: A1 - Application number: 14/147,970 - Filed: 2014-01-06 - Published: 2014-07-10 - Earliest claimed: 2013-01-08 - Assignees: CLAAS Saulgau GmbH - Applicants: Claas Saulgau GmbH - Inventors: Jasper Jeninga; Florian Dirlewanger; Andreas Mock - Web page: https://patentgrep.com/patent/US20140196109A1 ## CPC - G06F 21/445: {by mutual authentication, e.g. between devices or programs} - H04L 9/083: {involving central third party, e.g. key distribution center [KDC] or trusted third party [TTP]} - H04L 9/3273: {for mutual authentication (network architectures or network communication protocols for achieving mutual authentication in a packet data network H04L63/0869)} - H04L 63/08: {for authentication of entities (cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32)} - H04L 67/12: specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method for the authentication of at least two agricultural devices coupled via a data bus includes subjecting the each of the agricultural devices to authentication, automatically and independently of every of the agricultural device by use of an authentication device, which is also coupled to the data bus. The method also includes allowing a direct data exchange or indirect data exchange between the successfully authenticated agricultural devices, automatically. If authentication of the at least two data devices is unsuccessful, data exchange between the unsuccessfully authenticated agricultural devices is disallowed. ## Claims ### Claim 1 A method for authenticating of at least two agricultural devices coupled via a data bus, comprising the steps of: coupling an authentication device and the at least two agricultural devices to the data bus; utilizing the authentication device to authenticate each of the at least two agricultural devices coupled to the data bus automatically and independently; upon successful authentication of the at least two agricultural devices, allowing direct data exchange or indirect data exchange between the successfully authenticated agricultural devices, automatically; and upon unsuccessful authentication, disallowing direct data exchange or indirect data exchange between the unsuccessfully authenticated agricultural devices. ### Claim 2 (depends on 1) The method according to claim 1, wherein the step of utilizing the is authentication device to authenticate each of the at least two agricultural devices coupled to the data bus includes a step of verifying the authentication device via a particular agricultural device and a step of verifying the particular agricultural device via the authentication device. ### Claim 3 (depends on 2) The method according to claim 2, wherein the step of verifying the authentication device via a particular agricultural device includes: transmitting, by the particular agricultural device, an identification number (ID-LGi) stored in a control device thereof and a random number (Z1) determined by the control device thereof to the authentication device; determining, by the authentication device, a first de-vice key (KEY1-A-LGi) on the basis of the identification number (ID-LGi) transmitted by the particular agricultural device; determining, by the authentication device, a second device key (KEY2-A-LGi) on the basis of the first device key (KEY1-A-LGi) and the random number (Z1) transmitted by the particular agricultural device; transmitting, by the authentication device, the second device key (KEY2-A-LGi) and a random number (Z2) determined by the authentication device to the control device of the particular agricultural device; and determining, by the particular agricultural device, a second device key (KEY2-LGI) on the basis of a first device key (KEY1-LGi) stored in the control device thereof and on the basis of a random number (Z1) determined thereby and comparing the second device key (KEY2-LGi) determined thereby with the second device key (KEY2-A-LGi) determined and transmitted by the authentication device. ### Claim 4 (depends on 3) The method according to claim 3, wherein the step of verifying the particular agricultural device via the authentication device comprises the steps of: determining, by the particular agricultural device, a third device key (KEY3-LGi) on the basis of the first device key (KEY1-LGi) stored in the control device thereof and on the basis of the random number (Z2) transmitted by the authentication device and transmitting the third device key (KEY3-LGi) to the authentication device; and determining, by the authentication device, a third device key (KEY3-A-LGi) on the basis of the first device key (KEY1-A) determined thereby and on the basis of the random number (Z2) determined thereby, and comparing the random number (Z2) with the third device key (KEY3-LGI) determined and transmitted by the particular agricultural device. ### Claim 5 (depends on 4) The method according to claim 4, wherein upon successful verification of the authentication device and the particular agricultural device, the particular agricultural device is successfully authenticated. ### Claim 6 (depends on 1) The method according to claim 1, further comprising carrying out an indirect data exchange between successfully authenticated agricultural devices via the authentication device. ### Claim 7 (depends on 1) The method according to claim 1, further comprising a direct data exchange between successfully authenticated agricultural devices while bypassing the authentication device. ### Claim 8 (depends on 7) The method according to claim 7, wherein the bypassing of the authentication device includes: determining, by the authentication device, a fourth device key (KEY4-A-LG10) for the first agricultural device on the basis of a further random number (Z3) determined thereby and on the basis of a first device key (KEY1-A-LG10) determined thereby for a first agricultural device; determining, by the authentication device, a combination key (KEYC-A); determining, by the authentication device, a system key (KEYC-A-LG10) for the first agricultural device on the basis of the first device key (KEY1-A-LG10), on the basis of the fourth device key (KEY4-A-LG10), and the combination key (KEYC-A); transmitting, by the authentication device, the system key (KEYC-A-LG10) for the first agricultural device (10) and the further random number (Z3) to the first agricultural device (10); determining, by the first agricultural device, a combination key (KEYC) on the basis of the system key (KEYC-A-LG10) and the further random number (Z3); determining, by the authentication device, a fourth device key (KEY4-A-LG11) for the second agricultural device on the basis of a further random number (Z4) determined thereby and on the basis of a first device key (KEY1-A-LG11) determined for a second agricultural device; determining, by the authentication device, a system key (KEYC-A-LG11) for the second agricultural device on the basis of the first device key (KEY1-A-LG11), on the basis of the fourth device key (KEY4-A-LG11) and on the basis of the combination key (KEYC-A); transmitting, by the authentication device, the system key (KEYC-A-LG11) together with the further random number (Z4) to the second agricultural device (11); determining, by the second agricultural device, the combination key (KEYC) on the basis of the system key (KEYC-A-LG11) and the further random number (Z4); and using, by the first agricultural device and the second agricultural device, the same determined combination key (KEYC) for the encoded, direct data exchange. ### Claim 9 (depends on 1) An authentication device configured for authenticating at least two agricultural devices coupled via a data bus utilizing the method of claim 1. ### Claim 10 (depends on 1) A computer program product comprising program code means embodied in a non-transitory computer readable medium for carrying out all steps of the method according to claim 1, when the program code means is run on a computer or control device.