Switching between secured media devices

• US 20070260870A1
• Filed: 05/08/2006
• Published: 11/08/2007
• Est. Priority Date: 05/08/2006
• Status: Active Grant

• Current Assignee: Audiocodes Limited
• Original Assignee: Audiocodes Limited
• Inventors: Idan, Ofer, Nissan, Yuval
• Granted Patent: US 7,944,814 B2
• Time in Patent Office: Days
• US Class Current: 713/150
• CPC Class Codes: H04L 2463/121 Timestamp cryptographic mechanisms or cryptographic arrangements involving time stamps H04L9/3297
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload
• CPC Class Codes: H04L 65/1083 In-session procedures
• CPC Class Codes: H04L 65/1101 Session protocols
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/80 Responding to QoS
• CPC Class Codes: H04L 67/1001 for accessing one among a plurality of replicated servers
• CPC Class Codes: 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

Abstract

A system, method and apparatus for communication is provided which includes maintaining a primary and a secondary network media devices at substantially similar encryption state, wherein the secondary network media device is a redundant network media device. Similar encryption state may be maintained by copying reception and transmission switchover parameters from the primary network media device to the redundant network media device, at least once per 2^X packets, and preferably every 2¹³ packets that are either transmitted by, or received at, the primary network media device. The redundant network media device may receive packets by utilizing copied reception switchover parameters and transmit packets by estimating transmission switchover parameters based on copied transmission switchover parameters. The reception and transmission switchover parameters may be associated with Secure Real-time Transport Protocol or with PacketCable protocol. A communication system is also provided, which utilizes the communication method. The communication system may include several primary network media devices and a central network device to which switchover parameters may be copied from each primary network media device, and from which switchover parameters associated with a failing primary network media device may be copied to the redundant network media device.

Claims

1. A method of communication, comprising:

maintaining primary and secondary network media devices at a substantially similar encryption state, wherein the secondary network media device is a redundant network media device.

2. The method according to claim 1, wherein maintaining comprises:

copying reception and transmission switchover parameters from the primary network media device to the redundant network media device.

3. The method according to claim 2, wherein copying occurs at least once per 2^X packets that are either transmitted by, or received at, the primary network media device.

4. The method according to claim 3, wherein X=13.

5. The method according to claim 2, wherein the redundant network media device receives packets by utilizing copied reception switchover parameters.

6. The method according to claim 2, wherein the redundant network media device transmits packets by estimating current transmission switchover parameters.

7. The method according to claim 6, wherein the current transmission switchover parameters are estimated based on copied transmission switchover parameters.

8. The method according to claim 2, wherein the switchover parameters are associated with Secure Real-time Transport Protocol.

9. The method according to claim 2, wherein the reception and transmission switchover parameters are associated with PacketCable protocol.

10. The method according to claim 2, wherein switchover parameters comprises:

one or more of packet time stamp, packet sequence number, rollover counter and RTCP index.

11. The method according to claim 2, wherein switchover parameters comprises:

one or more of packet time stamp, Nwrap and RTCP sequence number.

12. The method according to claim 1, wherein the redundant network media device backs-up several primary network media devices.

13. The method according to claim 12, wherein switchover parameters are copied from a network media device to a central network device, and switchover parameters associated with a failing primary network media device are copied from said central network device to the redundant network media device.

14. A communication system, comprising:

a primary network media device; and

a secondary network media device wherein the secondary network media device is a redundant network media device;

wherein said primary and secondary network media devices are maintained at substantially similar encryption state.

15. The communication system according to claim 14, wherein maintaining comprises:

copying reception and transmission switchover parameters from the primary network media device to the redundant network media device.

16. The communication system according to claim 15, wherein copying occurs once per 2^X packets that are either transmitted by, or received at, the primary network media device.

17. The communication system according to claim 16, wherein X=13.

18. The communication system according to claim 15, wherein the redundant network media device receives packets by utilizing copied reception switchover parameters and transmits packets by estimating current transmission switchover parameters.

19. The communication system according to claim 18, wherein the redundant network media device estimates the current transmission switchover parameters based on copied transmission switchover parameters.

20. The communication system according to claim 15, wherein the reception and transmission switchover parameters are associated with Secure Real-time Transport Protocol.

21. The communication system according to claim 15, wherein the reception and transmission switchover parameters are associated with PacketCable protocol.

22. The communication system according to claim 15, wherein switchover parameters comprises:

one or more of packet time stamp, packet sequence number, rollover counter and RTCP index.

23. The communication system according to claim 15, wherein switchover parameters comprises:

one or more of packet time stamp, Nwrap and RTCP sequence number.

24. The communication system according to claim 14, wherein the redundant network media device backs-up several primary network media devices.

25. The communication system according to claim 24, further comprising a central network device to which switchover parameters are copied from each primary network media device, wherein said central network device is adapted to copy switchover parameters associated with a failing primary network media device to the redundant network media device.

26. The communication system according to claim 25, wherein the central network device comprises a storage array for storing switchover parameters associated with the respective primary network media devices.

27. A primary network media device adapted to maintain a secondary network media device used as a redundant network media device substantially at similar encryption state.

28. The primary network device according to claim 27, wherein the primary network media device maintains the redundant network media device substantially at similar encryption state by copying reception and transmission switchover parameters to said redundant network media device.

29. The primary network device according to claim 28, wherein copying occurs once per 2^X packets that are either transmitted by, or received at, the primary network media device.

30. The primary network media device according to claim 29, wherein X=13.

31. The primary network media device according to claim 28, wherein the reception and transmission switchover parameters are associated with Secure Real-time Transport Protocol.

32. The primary network media device according to claim 28, wherein the reception and transmission switchover parameters are associated with PacketCable protocol

33. The primary network media device according to claim 28, wherein switchover parameters comprises:

one or more of packet time stamp, packet sequence number, rollover counter and RTCP index.

34. The primary network media device according to claim 28, wherein switchover parameters comprises:

one or more of packet time stamp, Nwrap and RTCP sequence number.

35. The primary network media device according to claim 27, further comprising a central network device to which the primary network media device copies switchover parameters, wherein said central network device is adapted to copy said switchover parameters to the redundant network media device if said primary network media device fails to provide service.

36. A redundant network media device adapted to be maintained substantially at similar encryption state as a primary network media device.

37. The redundant network media device according to claim 36, wherein maintained comprises:

copying reception and transmission switchover parameters from the primary network media device to the redundant network media device.

38. The redundant network media device according to claim 36, wherein copying occurs once per 2^X packets that are either transmitted by, or received at, the primary network media device.

39. The redundant network media device according to claim 37, wherein X=13.

40. The redundant network media device according to claim 37, wherein said redundant network media device receives packets by utilizing copied reception switchover parameters.

41. The redundant network media device according to claim 37, wherein said redundant network media device transmits packets by estimating current transmission switchover parameters

42. The redundant network media device according to claim 37, wherein the redundant network media device estimates the current transmission switchover parameters based on copied transmission switchover parameters.

43. The redundant network media device according to claim 37, wherein the reception and transmission switchover parameters are associated with Secure Real-time Transport Protocol.

44. The redundant network media device according to claim 37, wherein the reception and transmission switchover parameters are associated with PacketCable protocol.

45. The redundant network media device according to claim 37, wherein switchover parameters comprises:

one or more of packet time stamp, packet sequence number, rollover counter and RTCP index.

46. The redundant network media device according to claim 37, wherein switchover parameters comprises:

one or more of packet time stamp, Nwrap and RTCP sequence number.

47. The redundant network media device according to claim 37, wherein the redundant network media device is adapted to back up several primary network media devices.

48. The redundant network media device according to claim 47, further comprising a central network device to which switchover parameters are copied from a primary network media device, wherein said central network device is adapted to copy switchover parameters associated with a failing primary network media device to the redundant network media device.