Granted Patent B2

US 8,621,223 · App. 12/164,814 · Granted Dec 31, 2013

Abstract

Claims (75)

1. A method of verifying integrity of a digital file comprising:

labeling, in a first network, the digital file prior to exposure to a foreign environment, the first network having a first security classification level, wherein labeling comprises:

creating a header label comprising an identification of the first security classification level;

appending the header label to the digital file;

hashing the digital file, together with the appended header label, to obtain a first hash value;

signing the first hash value to create a digital signature;

creating a signature label comprising one or both of the first hash value and the digital signature; and

appending the signature label to the digital file; and

validating, in a second network, the digital file subsequent to exposure to the foreign environment, the second network having a second security classification level that is different from the first security classification level, wherein validating comprises:

hashing the digital file to obtain a second hash value;

retrieving the first hash value from the signature label;

comparing the first hash value and second hash value; and

removing the signature label from the digital file.

2. The method of verifying integrity of a digital file of claim 1 , the validating the digital file subsequent to exposure to the foreign environment further comprising removing the header label from the digital file.

3. The method of verifying integrity of a digital file of claim 1 , further comprising:

performing a second labeling, in the first network, on the digital file prior to exposure to the foreign environment, wherein labeling comprises:

creating a second header label comprising an identification of a third security classification level;

appending the second header label to the digital file;

hashing the digital file, together with the second header label, to obtain a third hash value;

signing the third hash value to create a second digital signature;

creating a second signature label comprising one or both of the third hash value and the second digital signature; and

appending the second signature label to the digital file.

4. The method of verifying integrity of a digital file of claim 1 , further comprising:

verifying, before release to the foreign environment, that the digital file has been authorized for release to the foreign environment.

5. The method of verifying integrity of a digital file of claim 4 , wherein verifying comprises:

hashing the digital file to obtain a third hash value;

retrieving the first hash value from the signature label; and

comparing the first hash value and third hash value.

6. A method of verifying integrity of a digital file comprising:

labeling the digital file prior to exposure to a foreign environment, wherein labeling comprises:

creating a header label comprising an identification of a security classification level of a network;

appending the header label to the digital file;

hashing the digital file, together with the appended header label, to obtain a first hash value;

signing the first hash value to create a digital signature;

creating a signature label comprising one or both of the first hash value and the digital signature; and

appending the signature label to the digital file.

7. The method of verifying integrity of a digital file of claim 6 , further comprising:

validating the digital file subsequent to exposure to the foreign environment, wherein validating comprises:

hashing the digital file, together with the appended header label, to obtain a second hash value;

retrieving the first hash value from the signature label; and

comparing the first hash value and second hash value.

8. The method of verifying integrity of a digital file of claim 7 , further comprising removing the signature label from the digital file after validating the digital file.

9. The method of verifying integrity of a digital file of claim 7 , wherein validating the digital file subsequent to exposure to the foreign environment further comprises removing the header label from the digital file.

10. The method of verifying integrity of a digital file of claim 6 , wherein appending the signature label to the digital file renders the digital file unreadable until the signature label is removed from the digital file.

11. A method of verifying integrity of a digital file comprising:

receiving, in a first network, the digital file subsequent to exposure to a foreign environment, the first network having a first security classification level, the digital file comprising:

an appended header label comprising an identification of a second security classification level of a second network, the second security classification level being different from the first security classification level; and

an appended signature label comprising one or both of a first hash value and a digital signature; and

validating the digital file, wherein validating comprises:

hashing the digital file, together with the appended header label, to obtain a second hash value;

retrieving the first hash value from the signature label; and

comparing the first hash value and second hash value.

12. The method of verifying integrity of a digital file of claim 11 , further comprising:

labeling the digital file prior to exposure to the foreign environment, wherein labeling comprises:

hashing the digital file, together with the appended header label, to obtain the first hash value;

signing the first hash value to create the digital signature;

creating the signature label comprising one or both of the first hash value and the digital signature; and

appending the signature label to the digital file.

13. The method of verifying integrity of a digital file of claim 11 , further comprising removing the signature label from the digital file after validating the digital file.

14. The method of verifying integrity of a digital file of claim 13 , wherein appending the signature label to the digital file renders the digital file unreadable until the signature label is removed from the digital file.

15. Logic encoded in non-transitory computer-readable media operable, when executed on a processor, to:

label, in a first network, a digital file prior to exposure to a foreign environment, the first network having a first security classification level, wherein label comprises:

creating a header label comprising an identification of the first security classification level;

appending the header label to the digital file;

hashing the digital file, together with the appended header label, to obtain a first hash value;

signing the first hash value to create a digital signature;

creating a signature label comprising one or both of the first hash value and the digital signature; and

appending the signature label to the digital file; and

validate, in a second network, the digital file subsequent to exposure to the foreign environment, the second network having a second security classification level that is different from the first security classification level, wherein validate comprises:

hashing the digital file, together with the appended header label, to obtain a second hash value;

retrieving the first hash value from the signature label; and

comparing the first hash value and second hash value.

16. The logic encoded in computer-readable media of claim 15 , further operable, when executed on a processor, to remove the signature label from the digital file after validating the digital file.

17. The logic encoded in computer-readable media of claim 15 , wherein appending the signature label to the digital file renders the digital file unreadable until the signature label is removed from the digital file.

18. The logic encoded in computer-readable media of claim 15 , wherein validating the digital file subsequent to exposure to the foreign environment further comprises removing the header label from the digital file.

Assignments (12)