Security key input system and method using one-time keypad

1. A security key input system using a one-time keypad, comprising:

an input terminal and an output terminal communicating with each other via near field communication (NFC),

wherein the input terminal comprises:

a first controller generating the one-time keypad when a second NFC interface of the output terminal is recognized;

a first display outputting the one-time keypad in a first form of a blank keypad with no key symbols or numbers, security key entry performed on the blank keypad; and

a first NFC interface providing the one-time keypad to the output terminal through NFC,

wherein the output terminal comprises:

a second display;

the second NFC interface receiving the one-time keypad from the input terminal through the first NFC interface; and

a second controller outputting the one-time keypad received from the second NFC interface on the second display in a second form of a keypad with key symbols or numbers,

wherein when the one-time keypad is generated, the generated one-time keypad is stored in a storage unit of the input terminal through NFC, and a storage state is maintained until the storage state is canceled by a security key input, and

wherein the one-time keypad is generated based on a shared key shared between the input terminal and the output terminal and a synchronization key corresponding to a generation time.

2. The security key input system of claim 1 , wherein the second controller outputs the one-time keypad for a preset time, and then ends the output of the one-time keypad.

3. The security key input system of claim 1 , wherein the second NFC interface is implemented as an external interface, and installed in the output terminal.

4. The security key input system of claim 1 , wherein the input terminal comprises an ATM (Automated Teller Machine), door lock, safe or computer.

5. The security key input system of claim 4 , wherein the one-time keypad comprises a key arrangement that is randomly set, and the key arrangement is changed whenever the one-time keypad is generated.

6. The security key input system of claim 4 , wherein a number of one-time keypads to be generated is equal to a number of security keys to be inputted, and a one-time keypad is provided in response to each security key input.

7. The security key input system of claim 4 , wherein the first controller determines whether the security key inputted from the user coincides with a preset code, through the one-time keypad, and outputs a determination result through a color change of the first display or a sound output.

8. The security key input system of claim 1 , wherein the first controller is configured to:

generate a first one-time keypad corresponding to a first generation time; and

generate a second one-time keypad corresponding to a second generation time,

wherein the first one-time keypad matches the second one-time keypad when the first generation time and the second generation time belong to a same predetermined unit time.

9. A security key input method using a one-time keypad, comprising the steps of:

(A) recognizing, by an input terminal, a contact of an output terminal through an NFC module;

(B) generating, by the input terminal, the one-time keypad when the NFC module of the output terminal is recognized;

(C) transmitting, by the input terminal, the generated one-time keypad to the output terminal;

(D) outputting, by the output terminal, the received one-time keypad in a first form of a keypad with key symbols or numbers;

(E) outputting, by the input terminal, the one-time keypad in a second form of a blank keypad with no key symbols or numbers, security key entry performed on the blank keypad, and receiving a security key, entered on the blank keypad, from a user; and

(F) determining, by the input terminal, whether the security key inputted from the user coincides with a preset code, through the one-time keypad, and determining whether the security key is correct or wrong,

wherein when the one-time keypad is generated, the generated one-time keypad is stored in a storage unit of the input terminal through NFC, and a storage state is maintained until the storage state is canceled by a security key input, and

wherein the one-time keypad is generated based on a shared key shared between the input terminal and the output terminal and a synchronization key corresponding to a generation time.

10. The security key input method of claim 9 , wherein the step (D) of generating the one-time keypad is continued for a preset time, and then ended.

11. The security key input method of claim 9 , further comprising the step (G) of outputting a determination result to the user.

12. The security key input method of claim 11 , wherein the determining whether the security key coincides with the preset code and the outputting the determination result are performed whenever the user inputs the security key.

13. The security key input method of claim 12 , wherein the one-time keypad is generated according to a generation command inputted by the user.

14. The security key input method of claim 11 , wherein keys of the one-time keypad are distinguished by identification symbols or colors.

15. The security key input method of claim 11 , wherein a number of one-time keypads to be generated is equal to a number of security keys to be inputted, and a one-time keypad is provided in response to each security key input.

16. The security key input method of claim 9 , wherein the one-time keypad comprises a key arrangement that is set according to an arrangement change command from the user.

17. The security key input method of claim 16 , wherein keys of the one-time keypad are distinguished by identification symbols or colors.

18. The security key input method of claim 9 , wherein the generating of the one-time keypad comprises:

generating a first one-time keypad corresponding to a first generation time; and

generating a second one-time keypad corresponding to a second generation time,

wherein the first one-time keypad matches the second one-time keypad when the first generation time and the second generation time belong to a same predetermined unit time.