Methods for secure data storage
Embodiments include a method for secure data storage including constructing an encryption key from a plurality of key elements, the constructing including distributing the plurality of key elements to a plurality of key maintenance entities, each of the plurality of key maintenance entities employing a plurality of independent safe guards for their respective key elements of the plurality of key elements; and requiring access to the plurality of key elements to construct the encryption key. The method includes receiving a subset of the plurality of key elements via a twice-encrypted communications channel; and regenerating the encryption key at the client node; and after encrypting data, deleting the subset of the plurality of key elements received over the twice-encrypted communications channel, retaining any of the plurality of key elements previously stored at the client node.
1. A method comprising:
transmitting, by a first node, N data packets between the first node and a second node;
measuring, by the first node, N first travel times for the N data packets within a first loop from the first node to the second node and back to the first node;
determining, by the first node, N first-node bits based on the N first travel times;
receiving, from the second node, M second-node error-detection bits and K second-node parity bits, wherein the M second-node error-detection bits and the K second-node parity bits are derived from N second-node bits based on a second loop from the second node to the first node and back to the second node, wherein the M second-node error-detection bits are generated from a one-way function applied to the N second-node bits;
combining the N first-node bits and the K second-node parity bits into a candidate code word;
decoding the candidate code word into N corrected first-node bits;
applying the one-way function to the N corrected first-node bits to generate M first-node error-detection bits;
responsive to detecting that the M first-node error-detection bits match the M second-node error-detection bits, utilizing at least some of the N corrected first-node bits to generate an encryption key;
exchanging secure communications with the second node utilizing the encryption key;
where N, M, and K are integer values.
2. The method of claim 1 , wherein determining the N first-node bits comprises:
determining an average travel time for the N first travel times;
assigning a bit value of 1 for each of the N data packets having a first travel time larger than the average travel time and assigning a bit value of 0 for each of the N data packets having a first travel time less than the average travel time, resulting in the N first-node bits.
3. The method of claim 1 , wherein the M second-node error-detection bits and the K second-node parity bits are derived from N second-node bits based on N second travel times for the N data packets within the second loop from the second node to the first node and back to the second node.
4. The method of claim 1 , further comprising deriving initial M first-node error-detection bits and K first-node parity bits from the N first-node bits based on the N first travel times for the N data packets within the first loop and transmitting the initial M first-node error-detection bits and the K first-node parity bits to the second node.
5. The method of claim 1 , further comprising:
receiving, from the second node, additional M second-node error-detection bits and additional K second-node parity bits, wherein the additional M second-node error-detection bits and the additional K second-node parity bits are derived from the N second-node bits based on the second loop, wherein the additional M second-node error-detection bits are generated from the one-way function applied to the N second-node bits;
combining the N first-node bits and the additional K second-node parity bits into a second candidate code word;
decoding the second candidate code word into additional N corrected first-node bits;
applying the one-way function to the additional N corrected first-node bits to generate additional M first-node error-detection bits;
responsive to detecting that the additional M first-node error-detection bits match the additional M second-node error-detection bits, utilizing at least some of the N corrected first-node bits to generate the encryption key.
6. The method of claim 1 , wherein a first part of the K second-node parity bits is received in a first message and a second part of the K second-node parity bits is received in a second message.
7. The method of claim 1 , further comprising:
generating reliability values for the N first-node bits;
selecting a subset of the N first-node bits that are more reliable based on the reliability values;
sending indices of the selected subset to the second node; and
generating the encryption key based on the selected subset.
8. The method of claim 1 , further comprising utilizing a predetermined hash function to select a subset of the N first-node bits to generate the encryption key.
9. The method of claim 1 , further comprising:
routing the first loop and the second loop through one or more relay nodes; and
measuring travel times through a plurality of routed first loops and a plurality of second loops, each measured travel time corresponding to a different route between the first node and the second node.
10. The method of claim 1 , further comprising:
transmitting a plurality of data packets from the first node to the second node, each of the plurality of data packets holding pseudo-random data; and
receiving, by the first node, a plurality of indices identifying successfully received data packets of the plurality of data packets.
11. An apparatus comprising:
a processor; and
a non-transitory computer-readable medium having stored instructions that are operative, when executed by the processor, to:
transmit, by a first node, N data packets between the first node and a second node;
measure, by the first node, N first travel times for the N data packets within a first loop from the first node to the second node and back to the first node;
determine, by the first node, N first node bits based on the N first travel times;
receive, from the second node, M second node error-detection bits and K second-node parity bits, wherein the M second-node error-detection bits and the K second-node parity bits are derived from N second-node bits based on a second loop from the second node to the first node and back to the second node, wherein the M second-node error-detection bits are generated from a one-way function applied to the N second-node bits;
combine the N first-node bits and the K second-node parity bits into a candidate code word;
decode the candidate code word into N corrected first-node bits;
apply the one-way function to the N corrected first-node bits to generate M first-node error-detection bits;
responsive to detecting that the M first-node error-detection bits match the M second-node error-detection bits, utilize at least some of the N corrected first-node bits to generate an encryption key;
exchange secure communications with the second node utilizing the encryption key;
where N, M, and K are integer values.
12. The apparatus of claim 11 , wherein determining the N first-node bits comprises:
determining an average travel time for the N first travel times;
assigning a bit value of 1 for each of the N data packets having a first travel time larger than the average travel time and assigning a bit value of 0 for each of the N data packets having a first travel time less than the average travel time, resulting in the N first-node bits.
13. The apparatus of claim 11 , wherein the M second-node error-detection bits and the K second-node parity bits are derived from N second-node bits based on N second travel times for the N data packets within the second loop from the second node to the first node and back to the second node.
14. The apparatus of claim 11 , wherein the instructions are further operative to derive initial M first-node error-detection bits and K first-node parity bits from the N first-node bits based on the N first travel times for the N data packets within the first loop and transmitting the initial M first-node error-detection bits and the K first-node parity bits to the second node.
15. The apparatus of claim 11 , wherein the instructions are further operative to:
receive, from the second node, additional M second-node error-detection bits and additional K second-node parity bits, wherein the additional M second-node error-detection bits and the additional K second-node parity bits are derived from the N second-node bits based on the second loop, wherein the additional M second-node error-detection bits are generated from the one-way function applied to the N second-node bits;
combine the N first-node bits and the additional K second-node parity bits into a second candidate code word;
decode the second candidate code word into additional N corrected first-node bits;
apply the one-way function to the additional N corrected first-node bits to generate additional M first-node error-detection bits;
responsive to detecting that the additional M first-node error-detection bits match the additional M second-node error-detection bits, utilize at least some of the N corrected first-node bits to generate the encryption key.
16. The apparatus of claim 11 , wherein a first part of the K second-node parity bits is received in a first message and a second part of the K second-node parity bits is received in a second message.
17. The apparatus of claim 11 , wherein the instructions are further operative to:
generate reliability values for the N first-node bits;
select a subset of the N first-node bits that are more reliable based on the reliability values;
send indices of the selected subset to the second node; and
generate the encryption key based on the selected subset.
18. The apparatus of claim 11 , wherein the instructions are further operative to utilize a predetermined hash function to select a subset of the N first-node bits to generate the encryption key.
19. The apparatus of claim 11 , wherein the instructions are further operative to:
route the first loop and the second loop through one or more relay nodes; and
measure travel times through a plurality of routed first loops and a plurality of second loops, each measured travel time corresponding to a different route between the first node and the second node.
20. The apparatus of claim 11 , wherein the instructions are further operative to:
transmit a plurality of data packets from the first node to the second node, each of the plurality of data packets holding pseudo-random data; and
receive, by the first node, a plurality of indices identifying successfully received data packets of the plurality of data packets.