Granted Patent B2

US 12,536,122 · App. 18/315,120 · Granted Jan 27, 2026

Inventor: Ravisankar Jakkula (Telangana, IN)

Assignee: KIDDE FIRE PROTECTION, LLC

G06F13/42G06F21/554H04L12/4013G06F2221/034

Abstract

Claims (77)

1 . A communications network comprising:

a bus electronically coupled to a first device and a second device;

wherein each of the first device and the second device is configured to utilize a currently-used baud rate to place messages on the bus and receive messages from the bus;

wherein the currently-used baud rate is valid for the messages placed on the bus and received from the bus by the first device and the second device for a duration of a currently-used communications time window;

wherein the first device and the second device are configured to perform multiple iterations of a baud-rate change (BRC) process; and

wherein each of the multiple iterations of the BRC process comprises:

synchronizing the first device and the second device to identify a new currently-applied communications time window during which a baud-rate switch operation is applied; and

applying the baud-rate switch operation to change the currently-used baud-rate to a new baud-rate that is valid for the messages placed on the bus and received from the bus by the first device and the second device for a duration of the new currently-applied communications time window.

2 . The communications network of claim 1 , wherein the first device is configured to detect error messages on the bus generated by a third device electronically coupled to the bus.

3 . The communications network of claim 2 , wherein the third device is not configured to perform the BRC process.

4 . The communications network of claim 3 , wherein the first device is configured to, responsive to detecting error messages on the bus generated by the third device, initiate counter-cyber-attack actions.

5 . The communications network of claim 4 , wherein the counter-cyber-attached actions are selected from the group consisting of:

pausing the bus;

shutting the bus down;

logging a cyber-attack event;

providing a notification of a potential malicious presence on the bus; and

requesting technical assistance.

6 . The communications network of claim 1 , wherein:

the currently-used communications time window is less than a malicious action time window; and

the malicious action time window defines a minimum time required by a third device electronically coupled to the bus to determine the currently-used baud-rate of communications between the first device and the second device without using the BRC process.

7 . The communications network of claim 6 , wherein:

the new currently-used communications time window is less than the malicious action time window; and

the malicious action time window further defines a minimum time required by the third device electronically coupled to the bus to determine the new currently-used baud-rate of communications between the first device and the second device without using the BRC process.

8 . The communications network of claim 1 , wherein:

synchronizing the first device and the second device comprises the first device broadcasting a baud-rate switch time over the bus;

the baud-rate switch operation comprises computing the new baud-rate from a data block transmitted over the bus; and

the data block is also used to perform bit timing operations.

9 . The communications network of claim 8 , wherein:

the communications network comprises a controller area networking (CAN) network;

the data block comprises:

a SYNC_SEG data segment;

a PROP_SEG data segment;

a PHASE_SEG1 data segment; and

a PHASE_SEG2 data segment; and

the new baud-rate is not one of a set of standard CAN network baud-rates.

10 . The communications network of claim 1 , wherein:

synchronizing the first device and the second device comprises the first device broadcasting a start message over the bus;

the baud-rate switch operation is responsive to the start message; and

the baud-rate switch operation comprises selecting the new baud-rate from stored baud-rate options.

11 . A method of operating a communications network, the method comprising:

using a first device and a second device electronically coupled to one another through a bus to perform multiple iterations of a baud-rate change (BRC) process;

wherein each of the first device and the second device is configured to utilize a currently-used baud rate to place messages on the bus and receive messages from the bus;

wherein the currently-used baud rate is valid for the messages placed on the bus and received from the bus by the first device and the second device for a duration of a currently-used communications time window;

wherein each of the multiple iterations of the BRC process comprises:

synchronizing the first device and the second device to identify a new currently-applied communications time window during which a baud-rate switch operation is applied; and

applying the baud-rate switch operation to change the currently-used baud-rate to a new baud-rate that is valid for the messages placed on the bus and received from the bus by the first device and the second device for a duration of the new currently-applied communications time window.

12 . The method of claim 11 further comprising using the first device to detect error messages on the bus generated by a third device electronically coupled to the bus.

13 . The method of claim 12 , wherein the third device is not configured to perform the BRC process.

14 . The method of claim 13 further comprising using the first device to, responsive to detecting error messages on the bus generated by the third device, initiate counter-cyber-attack actions.

15 . The method of claim 14 , wherein the counter-cyber-attached actions are selected from the group consisting of:

pausing the bus;

shutting the bus down;

logging a cyber-attack event;

providing a notification of a potential malicious presence on the bus; and

requesting technical assistance.

16 . The method of claim 11 , wherein:

the currently-used communications time window is less than a malicious action time window; and

the malicious action time window defines a minimum time required by a third device electronically coupled to the bus to determine the currently-used baud-rate of communications between the first device and the second device without using the BRC process.

17 . The method of claim 16 , wherein:

the new currently-used communications time window is less than the malicious action time window; and

the malicious action time window further defines a minimum time required by the third device electronically coupled to the bus to determine the new currently-used baud-rate of communications between the first device and the second device without using the BRC process.

18 . The method of claim 11 , wherein:

synchronizing the first device and the second device comprises the first device broadcasting a baud-rate switch time over the bus:

the baud-rate switch operation comprises computing the new baud-rate from a data block transmitted over the bus; and

the data block is also used to perform bit timing operations.

19 . The method of claim 18 , wherein:

the communications network comprises a controller area networking (CAN) network;

the data block comprises:

a SYNC_SEG data segment;

a PROP_SEG data segment;

a PHASE_SEG1 data segment; and

a PHASE_SEG2 data segment; and

the new baud-rate is not one of a set of standard CAN network baud-rates.

20 . The method of claim 11 , wherein:

synchronizing the first device and the second device comprises the first device broadcasting a start message over the bus;

the baud-rate switch operation is responsive to the start message; and

the baud-rate switch operation comprises selecting the new baud-rate stored baud-rate options.

Assignments (3)

Continuity (2)

References Cited (21)