METHOD AND APPARATUS FOR REDUCING COMMUNICATION SYSTEM DOWNTIME WHEN CONFIGURING A CRYTOGRAPHIC SYSTEM OF THE COMMUNICATION SYSTEM

• US 20100158251A1
• Filed: 03/08/2010
• Published: 06/24/2010
• Est. Priority Date: 01/13/2005
• Status: Active Grant

• Current Assignee: Allen D. Risley
• Original Assignee: Allen D. Risley
• Inventors: Risley, Allen D.
• Granted Patent: US 8,250,625 B2
• Time in Patent Office: Days
• US Class Current: 380/255
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 63/08 for authentication of entities cryptographic mechanisms or cryptographic arrangements for entity authentication H04L9/32
• CPC Class Codes: Y04S 40/20 Information technology specific aspects, e.g. CAD, simulation, modelling, system security

Abstract

Disclosed is a method and apparatus for reducing communication system downtime when enabling cryptographic operation of a cryptographic system of the communication system where the cryptographic system includes a first cryptographic device operatively coupled to a plurality of second cryptographic devices via a communication network of the communication system. The method includes causing a pass-through mode of the second cryptographic devices to be suspended, sequentially determining a state of each of the second cryptographic devices, causing the second cryptographic devices and the first cryptographic device to substantially simultaneously operate in a secure mode if each of the second cryptographic devices is determined to have a first state, and causing the second cryptographic devices and the first cryptographic device to operate in the pass-through mode if at least one of the plurality of second cryptographic devices is determined to have a second state.

Claims

1. A method for reducing communication system downtime when enabling cryptographic operation of a cryptographic system of the communication system upon receipt of a command to enable cryptographic communication, the cryptographic system including a first cryptographic device coupled to a plurality of second cryptographic devices via a communication network of the communication system, the method comprising the steps of:

causing a first mode of the first cryptographic device and the plurality of second cryptographic devices to be suspended;

the first cryptographic device sequentially determining a readiness state of each of the plurality of second cryptographic devices, wherein a first readiness state indicates said first cryptographic device or one of said plurality of second cryptographic devices is able to participate in synchronized cryptographic communications and a second readiness state indicates said first cryptographic device or one of said plurality of second cryptographic devices is not able to participate in synchronized cryptographic communications; and

causing the first cryptographic device and each of the plurality of second cryptographic devices to synchronously switch to operate in a second cryptographic mode if each of the plurality of second cryptographic devices is determined to have a first readiness state, wherein the first cryptographic mode is a pass-through mode rendering said first cryptographic device and one of said plurality of second cryptographic devices transparent to the communications network, and the second cryptographic mode is a secure mode enabling cryptographic operation on data transmitted via the communication network.

2. The method of claim 1, further comprising the step of causing the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if at least one of the plurality of second cryptographic devices is determined to have a second state, the first mode rendering the first cryptographic device and the plurality of second cryptographic devices transparent to the communication network.

3. The method of claim 1, further comprising the step of causing the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if at least one of the plurality of second cryptographic devices is not responsive to the first cryptographic device.

4. The method of claim 1, wherein the step of causing a first cryptographic mode of the first cryptographic device and the plurality of second cryptographic devices to be suspended comprises:

detecting receipt of a first command to synchronously enable said second cryptographic mode operation of the first cryptographic device and the plurality of second cryptographic devices; and

in response to detecting receipt of the first command, broadcasting a number of second commands to the first cryptographic device and the plurality of second cryptographic devices to cause the first cryptographic device and the plurality of second cryptographic devices to suspend the first cryptographic mode and switch to the second cryptographic mode.

5. The method of claim 4, wherein the step of sequentially determining the state of each of the plurality of second cryptographic devices comprises:

(a) transmitting a third command to one of the plurality of second cryptographic devices that has not transmitted a second message, the third command requesting a status of the one of the plurality of second cryptographic devices, the second message including an indication of the first state;

(b) detecting receipt of a first message from the one of the plurality of second cryptographic devices, the first message including a challenge value;

(c) encrypting the challenge value with an encryption key of the first cryptographic device to form an encrypted challenge value;

(d) transmitting a fourth command to the one of the plurality of second cryptographic devices, the fourth command including the encrypted challenge value;

(e) detecting receipt of the second message from the one of the plurality of second cryptographic devices, receipt of the second message indicating successful decryption and authentication of the encrypted challenge value; and

(f) iteratively repeating steps (a)-(e) until detecting receipt of the second message from each of the plurality of second cryptographic devices.

6. The method of claim 1, wherein the first cryptographic device comprises a first microcontroller, the first microcontroller having a first microprocessor and a first memory operatively coupled to the first microprocessor, and wherein each of the plurality of second cryptographic devices comprise a second microcontroller having a second microprocessor and a second memory operatively coupled to the second microprocessor.

8. The method of claim 1, wherein the first cryptographic device is configured to encrypt data transmitted by a master device of the communication system and to decrypt and authenticate data received by the master device when the first cryptographic device is operating in the second mode.

9. The method of claim 8, wherein each of the plurality of second cryptographic devices is configured to encrypt data transmitted by a corresponding intelligent electronic device operatively coupled to the second cryptographic device, and to decrypt and authenticate data subsequently received by the corresponding second intelligent electronic device when each of the plurality of second cryptographic devices is operating in the second mode.

10. The method of claim 9, wherein the communication system is configured to monitor an electric power system, and wherein the data is selected from the group consisting of an electric power system line current, an electric power system bus voltage, an electric power system switch status, a command from the first cryptographic device and a message from the plurality of second cryptographic devices.

11. The method of claim 1, wherein each of the first cryptographic device and the plurality of second cryptographic devices is placed in the first mode upon installation in the cryptographic system.

12. The method of claim 1, where in the communication system comprises a supervisory control and data acquisition (SCADA) system, and wherein the communication network comprises a SCADA communication network.

56. The method of claim 1, wherein the certain cryptographic setting comprises use of a particular cryptographic key.

7. (canceled)

13. A method for reducing communication system downtime when changing at least one parameter value of a cryptographic system of the communication system, the cryptographic system including a first cryptographic device operatively coupled to a plurality of second cryptographic devices via a communication network, each of the first cryptographic device and the plurality of second cryptographic devices operating in a second mode using a first set of parameter values, the method comprising:

detecting receipt of a first command to synchronously switch from a first cryptographic mode to a second cryptographic mode using a second set of parameter values for the plurality of second cryptographic devices and the first cryptographic device wherein the first cryptographic mode is a pass-through mode rendering said first device or one of said plurality of second devices transparent to the communications system and the second cryptographic mode is a secure mode enabling cryptographic operation o data transmitted via the communication system;

sequentially determining a state of each of the plurality of second cryptographic devices, wherein a first readiness state indicates said first device or one of said plurality of second devices is able to participate in synchronized cryptographic communications and a second readiness state indicates said first device or one of said plurality of second devices is not able to participate in synchronized cryptographic communications; and

causing the plurality of second cryptographic devices and the first cryptographic device to substantially simultaneously operate in the second mode using the second set of parameter values if each of the plurality of second cryptographic devices is determined to have the first state, wherein at least one of the second set of parameter values is different from the first set of parameter values.

14. The method of claim 13, further comprising the step of causing the plurality of second cryptographic devices and the first cryptographic device to operate in the second mode using the first set of parameter values if at least one of the plurality of second cryptographic devices is determined to have a second state.

15. The method of claim 13, further comprising the step of causing the plurality of second cryptographic devices and the first cryptographic device to operate in the second mode using the first set of parameter values if at least one of the plurality of second cryptographic devices is not responsive to the first cryptographic device.

16. The method of claim 13, wherein the step of sequentially determining the readiness state of each of the plurality of second cryptographic devices comprises:

(a) transmitting a second command to one of the plurality of second cryptographic devices that has not transmitted a second message, the second command requesting a status of the one of the plurality of second cryptographic devices, the second message including an indication of the first state;

(b) detecting receipt of a first message from the one of the plurality of second cryptographic devices, the first message including a challenge value;

(c) encrypting the challenge value with an encryption key of the first cryptographic device to form an encrypted challenge value;

(d) transmitting a third command to the one of the plurality of second cryptographic devices, the third command including the encrypted challenge value;

(e) detecting receipt of the second message from the one of the plurality of second cryptographic devices, receipt of the second message indicating successful decryption and authentication of the encrypted challenge value; and

(f) iteratively repeating steps (a)-(e) until detecting receipt of the second message from each of the plurality of second cryptographic devices.

17. The method of claim 13, wherein the first cryptographic device comprises a first microcontroller, the first microcontroller having a first microprocessor and a first memory operatively coupled to the first microprocessor, and wherein each of the plurality of second cryptographic devices comprise a second microcontroller having a second microprocessor and a second memory operatively coupled to the second microprocessor.

19. The method of claim 13, wherein the second mode enables cryptographic operation on data transmitted via the communication network.

20. The method of claim 13, wherein the first cryptographic device is configured to encrypt data transmitted by a master device of the communication system and to decrypt and authenticate data subsequently received by the master device when the first cryptographic device is operating in the second mode.

21. The method of claim 20, wherein each of the plurality of second cryptographic devices is configured to encrypt data transmitted by a corresponding intelligent electronic device operatively coupled to the second cryptographic device, and to decrypt and authenticate data subsequently received by the corresponding second intelligent electronic device when each of the plurality of second cryptographic devices is operating in the second mode.

22. The method of claim 21, wherein the communication system is configured to monitor and protect an electric power system, and wherein the data is selected from the group consisting of an electric power system line current, an electric power system bus voltage, an electric power system switch status, a command from the first cryptographic device and a message from the plurality of second cryptographic devices.

23. The method of claim 13, wherein the at least one of the second set of parameter values is selected from the group consisting of an encryption key, a cryptographic device configuration, a data rate, a maximum data frame length, a maximum dead time, a number of data bits, a number of stop bits and a parity bit configuration.

24. The method of claim 13, wherein the second set of parameters is installed in each of the first cryptographic device and the plurality of second cryptographic devices prior to detecting receipt of the first command to synchronously enable second mode operation using a second set of parameter values.

25. The method of claim 13, where in the communication system comprises a supervisory control and data acquisition (SCADA) system, wherein the communication network comprises a SCADA communication network, and wherein the cryptographic system includes a first mode that renders the first cryptographic device and the plurality of second cryptographic devices transparent to the SCADA communications network.

18. (canceled)

26. A method for reducing communication system downtime when enabling cryptographic operation of a cryptographic system of the communication system upon receipt of a command to enable cryptographic operation, the cryptographic system including a first cryptographic device operatively coupled to a plurality of second cryptographic devices via a communication network of the communication system, the method comprising the steps of:

The first cryptographic device sequentially determining a readiness state of each of the plurality of second cryptographic devices, wherein a first readiness state indicates said first device or one of said plurality of second devices is able to participate in synchronized cryptographic communications and a second readiness state indicates said first device or one of said plurality of second devices is not able to participate in synchronized cryptographic communications; and

causing a first cryptographic device and each of the plurality of second cryptographic devices to synchronously switch to operate in a second mode if the readiness state of each of the plurality of second cryptographic devices is determined to have the first state, wherein the first cryptographic mode is a pass-through mode rendering said first device or one of said plurality of second devices transparent to the communications system and the second mode is a secure mode that enables cryptographic operation on data transmitted via the communication system.

27. The method of claim 26, further comprising the step of causing a first mode of the first cryptographic device and the plurality of second cryptographic devices, the first mode comprising a cryptographic mode, rendering the first cryptographic device and the plurality of second cryptographic devices transparent to the communication network.

28. The method of claim 27, further comprising the step of causing the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if at least one of the plurality of second cryptographic devices is determined to have a second state.

29. The method of claim 27, further comprising the step of causing the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if at least one of the plurality of second cryptographic devices is not responsive to the first cryptographic device.

30. The method of claim 27, wherein the step of causing a first mode of the cryptographic device and the plurality of second cryptographic devices to be suspended comprises:

detecting receipt of a first command to synchronously enable second mode operation of the first cryptographic device and the plurality of second cryptographic devices; and

in response to detecting receipt of the first command, broadcasting a number of second commands to the first cryptographic device and the plurality of second cryptographic devices to cause the first cryptographic device and the plurality of second cryptographic devices to suspend the first mode.

31. The method of claim 30, wherein the step of sequentially determining the state of each of the plurality of second cryptographic devices comprises

(a) transmitting a third command to one of the plurality of second cryptographic devices that has not transmitted a second message, the third command requesting a status of the one of the plurality of second cryptographic devices, the second message including an indication of the first state;

(b) detecting receipt of a first message from the one of the plurality of second cryptographic devices, the first message including a challenge value;

(c) encrypting the challenge value with an encryption key of the first cryptographic device to form an encrypted challenge value;

(d) transmitting a fourth command to the one of the plurality of second cryptographic devices, the fourth command including the encrypted challenge value;

(e) detecting receipt of the second message from the one of the plurality of second cryptographic devices, receipt of the second message indicating successful decryption and authentication of the encrypted challenge value; and

(f) iteratively repeating steps (a)-(e) until detecting receipt of the second message from each of the plurality of second cryptographic devices.

32. The method of claim 26, wherein the first cryptographic device comprises a first microcontroller, the first microcontroller having a first microprocessor and a first memory operatively coupled to the first microprocessor, and wherein each of the plurality of second cryptographic devices comprise a second microcontroller having a second microprocessor and a second memory operatively coupled to the second microprocessor.

33. (canceled)

34. An apparatus for reducing communication system downtime when enabling cryptographic operation of a cryptographic system of the communication system, the communication system including a communication network, the apparatus comprising:

a first cryptographic device comprising a first microcontroller; and

a plurality of second cryptographic devices operatively coupled to the first cryptographic device via the communication network, each of the plurality of second cryptographic devices comprising a second microcontroller, wherein the first microcontroller is adapted to;

cause a first mode of the first cryptographic device and the plurality of second cryptographic devices to be suspended on reception of a first command, wherein the first cryptographic mode is a pass-through mode rendering said first cryptographic device or one of the plurality of second cryptographic devices transparent to the communication network, and a second cryptographic mode is a secure mode enabling cryptographic operations on data transmitted via the communication network,

sequentially determine a readiness state of each of the plurality of second cryptographic devices wherein the first readiness state indicates said first device or one of the plurality of second devices is able to participate in synchronized cryptographic communications, and a second readiness state indicates said first device or one of said plurality of second devices is not able to participate in synchronized cryptographic communications; and

cause the first cryptographic device and each of the plurality of second cryptographic devices to synchronously switch to operate in a second mode if each of the plurality of second cryptographic devices is determined to have the first state.

35. The apparatus of claim 34, wherein the first microcontroller is further adapted to cause the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if the readiness state of at least one of the plurality of second cryptographic devices is determined to have a second state.

36. The apparatus of claim 34, wherein the first microcontroller is further adapted to cause the first cryptographic device and the plurality of second cryptographic devices to operate in the first mode if at least one of the plurality of second cryptographic devices is not responsive to the first cryptographic device.

37. The apparatus of claim 34, wherein the first microcontroller is further adapted to:

detect receipt of a first command to synchronously enable second mode operation of the first cryptographic device and the plurality of second cryptographic devices; and

in response to detecting receipt of the first command, broadcast a number of second commands to the plurality of second cryptographic devices to cause the plurality of second cryptographic devices to suspend the first mode.

38. The apparatus of claim 37, wherein the first microcontroller is further adapted to:

(a) transmit a third command to one of the plurality of second cryptographic devices that has not transmitted a second message, the third command requesting a status of the one of the plurality of second cryptographic devices, the second message including an indication of the first state;

(b) detect receipt of a first message from the one of the plurality of second cryptographic devices, the first message including a challenge value;

(c) encrypt the challenge value with an encryption key of the first cryptographic device to form an encrypted challenge value;

(d) transmit a fourth command to the one of the plurality of second cryptographic devices, the fourth command including the encrypted challenge value;

(e) detect receipt of the second message from the one of the plurality of second cryptographic devices, receipt of the second message indicating successful decryption and authentication of the encrypted challenge value; and

(f) iteratively repeat steps (a)-(e) until detecting receipt of the second message from each of the plurality of second cryptographic devices.

39. The apparatus of claim 34, wherein the first microcontroller includes a first microprocessor and a first memory operatively coupled to the first microprocessor, and wherein each of the plurality of second microcontrollers include a second microprocessor and a second memory operatively coupled to the second microprocessor.

40. The apparatus of claim 34, wherein the first cryptographic device is configured to encrypt data transmitted by a master device of the communication system and to decrypt and authenticate data subsequently received by the master device when the first cryptographic device is operating in the second mode.

41. The apparatus of claim 40, wherein each of the plurality of second cryptographic devices is configured to encrypt data transmitted by a corresponding intelligent electronic device operatively coupled to the second cryptographic device, and to decrypt and authenticate data subsequently received by the corresponding second intelligent electronic device when each of the plurality of second cryptographic devices is operating in the second mode.

42. The apparatus of claim 41, wherein the communication system is configured to monitor an electric power system, and wherein the data is selected from the group consisting of an electric power system line current, an electric power system bus voltage, an electric power system switch status, a command from the first cryptographic device and a message from the plurality of second cryptographic devices.

43. The apparatus of claim 34, wherein each of the first cryptographic device and the plurality of second cryptographic devices is placed in the first mode upon installation in the cryptographic system.

44. The apparatus of claim 34, wherein the communication system comprises a supervisory control and data acquisition (SCADA) system, and wherein the communication network comprises a SCADA communication network

45. An apparatus for reducing communication system downtime when changing at least one parameter value of a cryptographic system of the communication system, the communication system including a communication network, the apparatus comprising:

a first cryptographic device operating in a second mode using a first set of parameter values, the first cryptographic device comprising a first microcontroller; and

a plurality of second cryptographic devices operatively coupled to the first cryptographic device via the communication network, each of the plurality of second cryptographic devices operating in a second cryptographic mode using a first set of parameter values, each of the plurality of second cryptographic devices comprising a second microcontroller, wherein a first cryptographic mode is a pass-through mode rendering said first device or one of said plurality of second devices transparent to the communication system, and the second cryptographic mode is a secure mode enabling cryptographic operation on data transmitted via the communication system, and wherein the first microcontroller is adapted to;

detect receipt of a first command to synchronously enable second mode operation using a second set of parameter values for the plurality of second cryptographic devices and the first cryptographic device,

sequentially determine a readiness state of each of the plurality of second cryptographic devices wherein a first readiness state indicates said first device or one of said plurality of second devices is able to participate in synchronized cryptographic communications and a second readiness state indicates said first device or one of said plurality of second devices is not able to participate in synchronized cryptographic communications, and

cause each of the plurality of second cryptographic devices and the first cryptographic device to synchronously switch to operate in the second mode using the second set of parameter values if each of the readiness state of the plurality of second cryptographic devices is determined to have the first state, and wherein at least one of the second set of parameter values is different from the first set of parameter values.

46. The apparatus of claim 45, wherein the first microcontroller is further adapted to cause the first cryptographic device and the plurality of second cryptographic devices to operate in the second mode using the first set of parameter values if at least one of the plurality of second cryptographic devices is determined to have a second state.

47. The apparatus of claim 45, wherein the first microcontroller is further adapted to cause the first cryptographic device and the plurality of second cryptographic devices to operate in the second mode using the first set of parameter values if at least one of the plurality of second cryptographic devices is not responsive to the first cryptographic device.

48. The apparatus of claim 45, wherein the first microcontroller is further adapted to:

(a) transmit a second command to one of the plurality of second cryptographic devices that has not transmitted a second message, the second command requesting a status of the one of the plurality of second cryptographic devices, the second message including an indication of the first state;

(b) detect receipt of a first message from the one of the plurality of second cryptographic devices, the first message including a challenge value;

(c) encrypt the challenge value with an encryption key of the first cryptographic device to form an encrypted challenge value;

(d) transmit a third command to the one of the plurality of second cryptographic devices, the third command including the encrypted challenge value;

(e) detect receipt of the second message from one of the plurality of second cryptographic devices, receipt of the second message indicating successful decryption and authentication of the encrypted challenge value; and

(f) iteratively repeat steps (a)-(e) until detecting receipt of the second message from each of the plurality of second cryptographic devices.

50. The apparatus of claim 45, wherein the second mode enables cryptographic operation on data transmitted via a communication network of the communication system.

51. The apparatus of claim 45, wherein the first cryptographic device is configured to encrypt data transmitted by a master device of the communication system and to decrypt and authenticate data subsequently received by the master device when the first cryptographic device is operating in the second mode.

52. The apparatus of claim 51, wherein each of the plurality of second cryptographic devices is configured to encrypt data transmitted by a corresponding intelligent electronic device operatively coupled to the second cryptographic device, and to decrypt and authenticate data subsequently received by the corresponding second intelligent electronic device when each of the plurality of second cryptographic devices is operating in the second mode.

53. The apparatus of claim 52, wherein the communication system is configured to monitor an electric power system, and wherein the data is selected from the group consisting of an electric power system line current, an electric power system bus voltage, an electric power system switch status, a command from the first cryptographic device and a message from the plurality of second cryptographic devices.

54. The apparatus of claim 45, wherein the second set of parameters is installed in each of the first cryptographic device and the plurality of second cryptographic devices prior to detecting receipt of the first command to synchronously enable second mode operation using a second set of parameter values.

55. The apparatus of claim 45, where in the communication system comprises a supervisory control and data acquisition (SCADA) system, wherein the communication network comprises a SCADA communication network, and wherein the cryptographic system includes a first mode comprising a cryptographic mode that renders the first cryptographic device and the plurality of second cryptographic devices transparent to the SCADA communication network.

49. (canceled)