# US 2017/0286242 A1 · Redundancy device, redundancy system, and redundancy method > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0286242 A1 - Document ID: US20170286242A1 - Status: Published application - Kind: A1 - Application number: 15/470,976 - Filed: 2017-03-28 - Published: 2017-10-05 - Earliest claimed: 2016-04-01 - Assignees: Yokogawa Electric Corporation - Applicants: Yokogawa Electric Corporation - Inventors: Takeshi OHNO; Nobuaki EMA - Web page: https://patentgrep.com/patent/US20170286242A1 ## CPC - G06F 11/2028: {eliminating a faulty processor or activating a spare} - G06F 11/1616: {where the redundant component is an I/O device or an adapter therefor} - G06F 11/2023: {Failover techniques} - G06F 11/2033: {switching over of hardware resources} - G06F 11/2038: {with a single idle spare processing component} - G06F 11/2041: {with more than one idle spare processing component} - G06F 11/2048: {where the redundant components share neither address space nor persistent storage} - G06F 11/3006: {where the computing system is distributed, e.g. networked systems, clusters, multiprocessor systems (multiprogramming arrangements G06F9/46; allocation of resources G06F9/50)} - G06F 11/3055: {Monitoring arrangements for monitoring the status of the computing system or of the computing system component, e.g. monitoring if the computing system is on, off, available, not available (error or fault processing without redundancy G06F11/0703; error detection or correction by redundancy in data representation G06F11/08; error detection or correction of the data by redundancy in operations G06F11/14; error detection or correction by redundancy in hardware G06F11/16)} - G06F 11/3419: {by assessing time} - H04L 12/40182: {by using a plurality of communication lines} - H04L 12/40195: {by using a plurality of nodes} - H04L 45/245: {Link aggregation, e.g. trunking} - H04L 69/40: for recovering from a failure of a protocol instance or entity, e.g. service redundancy protocols, protocol state redundancy or protocol service redirection (management of faults, events, alarms or notifications in data switching networks H04L41/06) - G06F 2201/81: Threshold - 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 redundancy device which is configured to communicate with a redundancy opposite device and perform a redundancy execution, the redundancy device includes receivers configured to receive individually HB signals transmitted from the redundancy opposite device, a calculator configured to calculate a number of normal communication paths among communication paths of the HB signals based on a reception result of the receivers, a comparator configured to compare a calculation result of the calculator with a predetermined threshold value, and a changer configured to change the redundancy device from a standby state to an operating state, or change the redundancy device from the standby state to a not-standby state in which the redundancy execution is released, based on the calculation result of the calculator and a comparison result of the comparator. ## Claims ### Claim 1 A redundancy device which is configured to communicate with a redundancy opposite device and perform a redundancy execution, the redundancy device comprising: receivers configured to receive individually HB signals transmitted from the redundancy opposite device; a calculator configured to calculate a number of normal communication paths among communication paths of the HB signals based on a reception result of the receivers; a comparator configured to compare a calculation result of the calculator with a predetermined threshold value; and a changer configured to change the redundancy device from a standby state to an operating state, or change the redundancy device from the standby state to a not-standby state in which the redundancy execution is released, based on the calculation result of the calculator and a comparison result of the comparator. ### Claim 2 (depends on 1) The redundancy device according to claim 1, wherein the threshold value is larger than or equal to one, and smaller than a number of communication paths of the HB signals. ### Claim 3 (depends on 1) The redundancy device according to claim 1, wherein the changer is configured to: change the redundancy device from the standby state to the operating state if the calculation result of the calculator is zero, and change the redundancy device from the standby state to the not-standby state if the calculation result of the calculator is larger than or equal to one, and smaller than or equal to the threshold value. ### Claim 4 (depends on 3) The redundancy device according to claim 3, wherein the standby state is continued if the calculation result of the calculator is larger than the threshold value. ### Claim 5 (depends on 3) The redundancy device according to claim 3, wherein the changer is configured to change the redundancy device from the not-standby state to the standby state if the calculation result of the calculator becomes larger than the threshold value after changing the redundancy device from the standby state to the not-standby state. ### Claim 6 (depends on 1) The redundancy device according to claim 1, further comprising: a storage which stores list information representing a relation of failure about communication paths of the HB signals. ### Claim 7 (depends on 6) The redundancy device according to claim 6, wherein the calculator is configured to calculate a number of substantially normal communication paths among the communication paths of the HB signals with reference to the list information stored in the storage. ### Claim 8 A redundancy system comprising: a first device; and a second device which is configured to communicate with the first device and perform a redundancy execution, wherein the second device comprising: receivers configured to receive individually HB signals transmitted from the first device; a calculator configured to calculate a number of normal communication paths among communication paths of the HB signals based on a reception result of the receivers; a comparator configured to compare a calculation result of the calculator with a predetermined threshold value; and a changer configured to change the second device from a standby state to an operating state, or change the second from the standby state to a not-standby state in which the redundancy execution is released, based on the calculation result of the calculator and a comparison result of the comparator. ### Claim 9 (depends on 8) The redundancy system according to claim 8, wherein the threshold value is larger than or equal to one, and smaller than a number of communication paths of the HB signals. ### Claim 10 (depends on 8) The redundancy system according to claim 8, wherein the changer is configured to: change the second device from the standby state to the operating state if the calculation result of the calculator is zero, and change the second device from the standby state to the not-standby state if the calculation result of the calculator is larger than or equal to one, and smaller than or equal to the threshold value. ### Claim 11 (depends on 10) The redundancy system according to claim 10, wherein the standby state is continued if the calculation result of the calculator is larger than the threshold value. ### Claim 12 (depends on 10) The redundancy system according to claim 10, wherein the changer is configured to change the second device from the not-standby state to the standby state if the calculation result of the calculator becomes larger than the threshold value after changing the second device from the standby state to the not-standby state. ### Claim 13 (depends on 8) The redundancy system according to claim 8, further comprising: a storage which stores list information representing a relation of failure about communication paths of the HB signals. ### Claim 14 (depends on 13) The redundancy system according to claim 13, wherein the calculator is configured to calculate a number of substantially normal communication paths among the communication paths of the HB signals with reference to the list information stored in the storage. ### Claim 15 (depends on 8) The redundancy system according to claim 8, further comprising: a third device which is configured to communicate with the first device and the second device, and perform a redundancy execution, wherein the second device is configured to continue the not-standby state or the standby state, or change from the not-standby state to the standby state, based on a reception result of HB signals transmitted from the third device. ### Claim 16 A redundancy method for a redundancy system which comprises a first device and a second device which is configured to communicate with the first device and perform a redundancy execution, the redundancy method comprising: receiving, by the second device, individually HB signals transmitted from the first device; calculating a number of normal communication paths among communication paths of the HB signals based on a reception result of the HB signals; comparing a calculation result of the number of normal communication paths with a predetermined threshold value; and changing the second device from a standby state to an operating state, or changing the second device from the standby state to a not-standby state in which the redundancy execution is released, based on the calculation result and a comparison result. ### Claim 17 (depends on 16) The redundancy method according to claim 16, wherein the threshold value is larger than or equal to one, and smaller than a number of communication paths of the HB signals. ### Claim 18 (depends on 16) The redundancy method according to claim 16, further comprising: changing the second device from the standby state to the operating state if the calculation result is zero; and changing the second device from the standby state to the not-standby state if the calculation result is larger than or equal to one, and smaller than or equal to the threshold value. ### Claim 19 (depends on 18) The redundancy method according to claim 18, further comprising: continuing the standby state if the calculation result is larger than the threshold value. ### Claim 20 (depends on 16) The redundancy method according to claim 16, further comprising: changing the second device from the not-standby state to the standby state if the calculation result becomes larger than the threshold value after changing the second device from the standby state to the not-standby state.