ELECTRONIC LOCK BOX WITH TIME-RELATED DATA ENCRYPTION BASED ON USER-SELECTED PIN

• US 20080309458A1
• Filed: 08/27/2008
• Published: 12/18/2008
• Est. Priority Date: 03/19/2004
• Status: Active Grant

• Current Assignee: SentriLock, LLC
• Original Assignee: Sentrilock Incorporated
• Inventors: Fisher, Scott R.
• Granted Patent: US 8,164,419 B2
• Time in Patent Office: Days
• US Class Current: 340/5.73
• CPC Class Codes: E05B 19/0005 Key safes E05B35/086 takes precedence
• CPC Class Codes: E05B 2047/0016 with linearly reciprocating motion
• CPC Class Codes: E05B 2047/002 Geared transmissions
• CPC Class Codes: E05B 47/0012 with rotary electromotors actuators with rotary electromotors per se H02K7/06, H02K23/68
• CPC Class Codes: E05B 47/0603 the detent moving rectilinearly
• CPC Class Codes: E05B 67/063 Padlocks with removable shackles
• CPC Class Codes: G07C 2009/00936 for key cabinets
• CPC Class Codes: G07C 9/0069 actuated in a predetermined sequence
• CPC Class Codes: G07C 9/00896 specially adapted for particular uses

Abstract

An electronic lock box contains a secure compartment for storing keys to a structure. A linear actuator moves in one direction opening the door to the secure compartment, and moves in the opposite direction releasing a shackle that holds the lock box to the structure. A lock box system uses an encryption algorithm to diversify user PIN data at a central computer, and stores that diversified information on a memory card for later use when the user attempts to access a lock box. The central computer and electronic lock box both keep track of system “epoch time,” and the memory card must be presented to the electronic lock box within a correct epoch time window for the diversified PIN data to be successfully decrypted and compared to the user'"'"'s PIN data that is entered on a keypad of the electronic lock box.

Claims

1. An electronic lock box apparatus, comprising:

an electrical power source, a controller circuit, a secure compartment having an access member actuated by a prime mover apparatus, a manual data entry apparatus, and a device reader port; and

a portable memory device that communicates with said device reader port, said portable memory device containing a plurality of memory elements that store a first data value, in which said first data value comprises a diversified numeric value that is;

(A) partially based on a previously-selected first user-determined code, (B) partially based on a predetermined encryption key, and (C) partially based on an epoch time value that was determined at an earlier real time, but (D) is not based upon an identification number of any electronic lock box apparatus;

wherein, said controller circuit is configured;

(a) to determine a present epoch time value, to determine a predetermined epoch time expiration period, to determine a cryptographic seed value for use with a data encryption algorithm;

(b) to read said first data value that is stored on said portable memory device;

(c) to decrypt said first data value using;

(i) said data encryption algorithm, based upon said cryptographic seed value, and (ii) said present epoch time value, but (iii) not using an identification number of any electronic lock box apparatus, to thereby determine a second data value;

(d) to receive a second user-determined code that is entered at said manual entry apparatus;

(e) to compare said second user-determined code to said second data value; and

(f) to allow access to said secure compartment, if said second user-determined code is exactly equal, digit by digit, to said second data value, by actuating said prime mover apparatus to open said access member.

2. The electronic lock box apparatus of claim 1, wherein said predetermined encryption key comprises a message digest function and a pseudo-random cryptographic key generator.

3. The electronic lock box apparatus of claim 1, wherein said cryptographic seed value is calculated by dividing said present epoch time value by said predetermined epoch time expiration period.

4. The electronic lock box apparatus of claim 1, wherein said previously-selected first user-determined code and said second user-determined code have the same numeric value.

5. The electronic lock box apparatus of claim 1, wherein said first user-determined code is mathematically diversified with said predetermined encryption key and said epoch time value, such that the first user-determined code becomes unrecognizable and cannot be reverse calculated after sufficient real time has run such that said predetermined epoch time expiration period has passed.

6. The electronic lock box apparatus of claim 1, further comprising a central clearinghouse computer that is placed into communication with said portable memory device, wherein said central clearinghouse computer generates said first data value, which is downloaded to said portable memory device and stored onto said plurality of memory elements.

7. The electronic lock box apparatus of claim 6, wherein said central clearinghouse computer generates said first data value at said earlier real time, using at least:

(a) an epoch time value corresponding to said earlier real time, (b) said predetermined epoch time expiration period, and (c) said previously-selected first user-determined code, which was earlier entered by said user to said central clearinghouse computer.

8. The electronic lock box apparatus of claim 1, wherein said second user-determined code is exactly equal to said second data value without discarding any digits from said second data value calculation.

9. The electronic lock box apparatus of claim 1, wherein said predetermined epoch time expiration period comprises a time interval for which said portable memory device will be valid.

10. The electronic lock box apparatus of claim 1, wherein said manual data entry apparatus comprises a keypad mounted on said electronic lock box apparatus.

11. The electronic lock box apparatus of claim 1, wherein said portable memory device comprises one of:

(a) a smart card;

(b) a data key, and (c) a USB-compatible memory device.

12. The electronic lock box apparatus of claim 1, wherein said controller circuit is further configured to allow an owner of said electronic lock box apparatus to set up an optional operating mode for the electronic lock box apparatus, such that the electronic lock box apparatus:

(a) allows access to the secure compartment only at predetermined time intervals, and

(b) otherwise prevents access to the secure compartment even;

(i) if a user has entered a correct password for said first user-determined code, and

(ii) if said portable memory device has not expired due to passage of real time.

13. The electronic lock box apparatus of claim 1, wherein said controller circuit is further configured to allow an owner of said electronic lock box apparatus to set up an optional operating mode for the electronic lock box apparatus, such that the electronic lock box apparatus:

(a) is placed into a lower security state, and

(b) the electronic lock box apparatus then allows access to the secure compartment without using a portable memory device if a user enters a predetermined contractor code on said manual data entry apparatus.

14. The electronic lock box apparatus of claim 13, wherein, the predetermined contractor code is a single-use code.

15. A method of operating an electronic lock box system, said method comprising:

(a) providing at least one electronic lock box having a secure compartment therein, a first computer circuit, a first memory circuit, a first device reader port, and a first data entry apparatus;

(b) providing a processing apparatus having a second computer circuit, a second memory circuit, a communications port for exchanging data with a second device reader port, and a second data entry apparatus;

(c) providing a portable memory device having a third memory circuit, and at least one data circuit pathway for communicating with a device reader port;

(d) at said second computer circuit;

(i) determining;

(A) a first present epoch time value, (B) a predetermined epoch time expiration period, (C) a first cryptographic seed value for use with a data encryption function, and (D) a user'"'"'s first identification code;

(ii) using said data encryption function, calculating a diversified value based upon both said first cryptographic seed value and said user'"'"'s first identification code;

(iii) coupling said portable memory device to said second device reader port, and communicating said diversified value to said portable memory device;

(e) at said at least one electronic lock box;

(i) coupling said portable memory device to said first device reader port, and communicating said diversified value from said portable memory device to at least one of said first computer circuit and said first memory circuit;

(ii) determining;

(A) a second present epoch time value, (B) a second cryptographic seed value; and

(C) determining a user'"'"'s second identification code from a manual entry at said first data entry apparatus;

(iii) using said data encryption function, decrypting said first diversified value based upon said second cryptographic seed value, resulting in a third identification code; and

(iv) comparing said user'"'"'s second identification code and said third identification code, and if they exactly match, permitting access to said secure compartment.

wherein;

(f) said user'"'"'s first identification code is a value that has been determined solely by a human user, and which was provided to said second computer circuit by said human user; and

(g) said diversified value is not based upon an identification number of any of said at least one electronic lock box.

16. The method of claim 15, wherein:

(a) said first cryptographic seed value is determined by dividing said first present epoch time value by said predetermined epoch time expiration period, and (b) said second cryptographic seed value is determined by dividing said second present epoch time value by said predetermined epoch time expiration period.

17. The method of claim 15, wherein said step of decrypting said first diversified value comprises a reverse calculation of said diversified value, which results in a numeric value that is equal to said user'"'"'s first identification code, if said predetermined epoch time expiration period has not expired.

18. The method of claim 15, wherein said predetermined epoch time expiration period comprises a time interval for which said portable memory device will be valid.

19. The method of claim 15, wherein said user'"'"'s second identification code is exactly equal to said third identification code, without discarding any digits from said third identification code'"'"'s calculation.

20. The method of claim 15, wherein said user'"'"'s first identification code is mathematically diversified with said predetermined encryption key and said epoch time value, such that the first user-determined code becomes unrecognizable and cannot be reverse calculated after sufficient real time has run such that said predetermined epoch time expiration period has passed.

21. The method of claim 15, further comprising the steps of:

setting up an optional operating mode for said at least one electronic lock box, thereby;

(a) allowing access to the secure compartment only at predetermined time intervals, and

(b) otherwise preventing access to the secure compartment even;

(i) if a user has entered a correct password for said first user-determined code, and

(ii) if said portable memory device has not expired due to passage of real time.

22. The method of claim 15, further comprising the steps of:

setting up an optional operating mode for said at least one electronic lock box, thereby;

(a) placing said at least one electronic lock box into a lower security state, and

(b) then allowing access to the secure compartment without using a portable memory device if a user enters a predetermined contractor code on said manual data entry apparatus.

23. The method of claim 22, wherein, the predetermined contractor code is a single-use code.