Generating a data audit trail for cross perimeter data transfer

1. A method implemented by a single computing device having a first perimeter and a second perimeter with access restrictions on resources between the first perimeter and the second perimeter, the first perimeter and the second perimeter each defining a logical separation within a memory of the single computing device, the method comprising:

receiving an input requesting a transfer of data from the first perimeter to the second perimeter;

identifying a first cross-perimeter policy associated with the first perimeter and a second cross-perimeter policy associated with the second perimeter, the first and second cross-perimeter policies defining, for each of the first and second perimeters respectively, one or more criteria for at least one of: permitting the transfer of data or requiring generation of an audit trail;

combining the first cross-perimeter policy and the second cross-perimeter policy to determine at least one of: whether the transfer of data is permitted or whether generation of the audit trail is required; and

in accordance with the determination resulting from the combining:

transferring data from the first perimeter to the second perimeter within the memory of the single computing device in response to the request, if it is determined that the transfer of data is permitted; and

generating a data transfer audit trail including transfer event information about the data transfer, if it is determined that generation of the audit trail is required.

2. The method of claim 1 , wherein the transfer event information comprises at least one of: an identifier identifying the data transfer; at least some content of the transferred data; a time-stamp of the data transfer; or a user ID associated with the data transfer request.

3. The method of claim 2 , wherein the first perimeter is an encrypted perimeter in which the data is encrypted, the method comprising:

decrypting the data prior to transferring data.

4. The method of claim 1 , wherein the data comprises any of a text string, image data, or audio data.

5. The method of claim 3 , further comprising:

storing the data audit trail in the encrypted perimeter; and

sending the data audit trail over a network to a server.

6. The method of claim 5 , wherein the data audit trail is sent to the server when one or more pre-determined criteria are met, the one or more predetermined criteria including one or more of: a pre-determined elapse of time; a pre-determined network connection for sending the data audit trail; or a pre-determined number of data transfers.

7. The method of claim 5 , comprising deleting the data audit trail from the encrypted perimeter after sending the data audit trail.

8. The method of claim 1 wherein:

both the first and second cross-perimeter policies define respective first and second criteria for permitting the transfer of data; and

as a result of the combining, it is determined that the transfer of data is Permitted if both the first and second criteria are met.

9. The method of claim 1 wherein:

both the first and second cross-perimeter policies define respective first and second criteria for requiring generation of the audit trail; and

as a result of the combining, it is determined that generation of the audit trail is required if at least one of the first or the second criteria are met.

10. The method of claim 1 comprising processing the data prior to the data transfer, wherein the transfer event information includes information identifying the processing.

11. A computing device configured with a first perimeter and a second perimeter that have respective resources and access restrictions therebetween, the first perimeter and the second perimeter each defining a logical separation within a memory of the single computing device, comprising:

a processor operable to:

receive an input requesting a transfer of data on the computing device from the first perimeter to the second perimeter;

identify a first cross-perimeter policy associated with the first perimeter and a second cross-perimeter policy associated with the second perimeter, the first and second cross-perimeter policies defining, for each of the first and second perimeters respectively, one or more criteria for at least one of: permitting the transfer of data or requiring generation of an audit trail;

combine the first cross-perimeter policy and the second cross-perimeter policy to determine at least one of: whether the transfer of data is permitted or whether generation of the audit trail is required; and

in accordance with the determination resulting from the combining:

transfer data from the first perimeter to the second perimeter within the memory of the single computing device in response to the request, if it is determined that the transfer of data is permitted; and

generate a data transfer audit trail including transfer event information about the data transfer, if it is determined that generation of the audit trail is required.

12. The device of claim 11 , wherein the transfer event information comprises at least one of: an identifier identifying the data transfer; at least some content of the transferred data; a time-stamp of the data transfer; or a user ID associated with the data transfer request.

13. The device of claim 12 , wherein the first perimeter is an encrypted perimeter in which the data is encrypted, the processor being operable to decrypt the data prior to transferring data.

14. The device of claim 11 , wherein the data comprises any of a text string, image data, or audio data.

15. The device of claim 13 , the processor being operable to:

store the data audit trail in the encrypted perimeter; and

send the data audit trail over a network to a server.

16. The device of claim 15 , wherein the data audit trail is sent to the server when one or more pre-determined criteria are met, the one or more predetermined criteria including one or more of: a pre-determined elapse of time; a pre-determined network connection for sending the data audit trail; or a pre-determined number of data transfers.

17. The device of claim 15 , the processor being operable to delete the data audit trail from the encrypted perimeter after sending the data audit trail.

18. The device of claim 11 wherein:

both the first and second cross-perimeter policies define respective first and second criteria for permitting the transfer of data; and

the processor is operable to: determine, as a result of the combining, that the transfer of data is permitted if both the first and second criteria are met.

19. The device of claim 11 wherein:

both the first and second cross-perimeter policies define respective first and second criteria for requiring generation of the audit trail; and

the processor is operable to: determine, as a result of the combining, that generation of the audit trail is required if at least one of the first or the second criteria are met.

20. The device of claim 11 the processor being operable to selectively process the data prior to the data transfer, wherein the transfer event information includes information identifying the processing.

21. A non-transitory computer readable medium having computer-executable instructions tangibly embodied thereon, the instructions, when executed by a single computing device configured with a first perimeter and a second perimeter that have respective resources and access restrictions therebetween, the first perimeter and the second perimeter each defining a logical separation within a memory of the single computing device, causing the single computing device to:

receive an input requesting a transfer of data on the computing device from the first perimeter to the second perimeter;

identify a first cross-perimeter policy associated with the first perimeter and a second cross-perimeter policy associated with the second perimeter, the first and second cross-perimeter policies defining, for each of the first and second perimeters respectively, one or more criteria for at least one of: permitting the transfer of data or requiring generation of an audit trail;

combine the first cross-perimeter policy and the second cross-perimeter policy to determine at least one of: whether the transfer of data is permitted or whether generation of the audit trail is required; and

in accordance with the determination resulting from the combining:

transfer data from the first perimeter to the second perimeter within the memory of the single computer device in response to the request; and

generate a data transfer audit trail including transfer event information about the data transfer.