KR100737181B1 - Apparatus and method for lightweight and resynchronous mutual authentication protocol for secure rfid system - Google Patents

Abstract

A device and a method for performing lightweight/resynchronous mutual authentication in a secure RFID system are provided to retry synchronization if the synchronization is mismatched and reduce database the amount of calculation while defending all kinds of attacks applied to the RFID system. An RFID tag(1) transmits the first and second hash value according to a synchronization value in response to a request of an RFID reader(2). The RFID reader generates a random number, transmits the random number and the request to the RFID tag, and transmits the first/second hash value received from the RFID tag and the random number generated from the RFID tag to a backend database(3). The backend database receives the first/second random number and the random number of the RFID tag from the RFID reader. The backend database finds an ID for a present session and a previous ID corresponding to the previous session according to a state of the previous session by comparing the first or second hash value with values stored in a hashed ID value field and a previous ID field.

Description

Apparatus and method for lightweight and resynchronous mutual authentication protocol for secure RFID system for low load and resynchronization

1 is a block diagram of a general RFID system.

2 is a view showing a mutual authentication device having low load and resynchronization characteristics and a method for a secure RFID system according to an embodiment of the present invention.

Figure 3 is a table comparing the stability according to the prior art and the present invention.

Figure 4 is a table comparing the amount of calculation according to the prior art and the present invention.

Explanation of symbols on the main parts of the drawings

10: backend database

20: RFID reader

30: RFID Tag

[1] A. Juels. “RFID Security and Privacy: A Research Survey,” RSA Laboratories, 2005.

[2] S. Lee, T. Asano and K. Kim. “RFID Mutual Authentication Scheme based on Synchronized Secret,” Information. In proceedings of the SCIS'06, 2006.

[3] K. Rhee, J. Kwak, S. Kim and D. Won. “Challenge-Response Based on RFID Authentication Protocol for Distributed Database Environment,” SPC'05, LNCS 3450, Springer-Verlag, 2005.

[4] D. Henrici and P. Muller. “Hash-based Enhancement of Location Privacy for Radio Frequency Identification Devices using Varying Identifiers,” In proceeding of the Second IEEE Annual Conference on Pervasive Computing and Communications Workshops, pp. 149-162, IEEE, 2004

[5] K. Rhee, J. Kwak, S. Kim and D. Won. “Challenge-Response Based on RFID Authentication Protocol for Distributed Database Environment,” SPC'05, LNCS 3450, Springer-Verlag, 2005.

[6] S. Lee, Y. Hwang, D. Lee and J. Lim. “Efficient Authentication for Low-cost RFID Systems,” ICCSA'05, LNCS 3480, pp. 619-627, Springer-Verlag, 2005

[7] T. Dimitriou, “A lightweight RFID protocol to protect against traceability and cloning attacks,” Security and Privacy for Emerging Areas in Communications Networks-2005. SecureComm 2005, pp. 59-66, Sept., 2005

The present invention relates to an RFID (Radio Frequency IDentification) system, and in particular, to prevent all the attacks applied to the RFID system to resynchronize when the synchronization is off, and to provide an effective RFID tag authentication system that reduces the amount of calculation of the DB The present invention relates to a mutual authentication device having low load and resynchronization characteristics and a method for a secure RFID system that is suitable.

In general, a RFID (Radion Frequency Identification) system is a non-contact automatic identification technology through wireless communication between a reader and a tag by using a small device called an RFID tag, and has many advantages such as rapid identification and miniaturization. Because of this, it was recognized as a means to replace the optical bar code and is currently used throughout the industry, such as supply chain management, inventory management.

However, wireless communication between the tag and the reader can easily expose the tag's information, and malicious attackers can use the tag owner's personal information through eavesdropping, spoofing attacks, replay attacks, and asynchronous synchronization attacks. In addition, the location can be tracked.

Therefore, although many alternatives have been proposed and studied as a countermeasure against these attacks, most existing studies do not satisfy all the security requirements for secure RFID systems. In addition, when designing the RFID protocol, the computational capacity of the tag was considered, and the computational amount of the back-end database was not considered. However, for practical RFID systems, not only RFID tags with limited capabilities, but also the amount of computation in the database must be considered.

1 is a block diagram of a general RFID system.

Where reference numeral 1 is an RFID tag, 2 is an RFID reader, and 3 is a backend database.

The prior art for such an RFID system is a "wireless recognition tag and its memory access method" (Korean Patent Office Publication No. 10-2006-0013097, filed August 06, 2004). However, this is a simple access control device that is vulnerable to security that allows data access only when the authentication code is received from the reader and the correct authentication code is sent.

There is also an "authentication method of a RFID tag with security function" (Korean Patent Office Publication No. 10-2004-0092670, filed April 25, 2003). However, since it propagates the unique code of the tag and the authentication password through the wireless section, it is vulnerable to security and has a much higher calculation amount by using 3DES (Data Encryption Standards). In contrast, the present invention classifies the attack into various kinds (replay attack, camouflage attack, location tracking attack, etc.) and uses a cryptographic technique for defending the attack. In addition, the present invention provides a resynchronozation function so that a normal tag operation can be performed in the next session even if one communication failure occurs intentionally or in error, and performs authentication function cryptographically and securely while searching for a tag in a database on the reader side. We developed a system that makes this easy and easy-to-authenticate calculation for tags and servers.

In addition, the present invention uses a cryptographic technique to classify the various attacks to date and prevent the attacks compared to the two patent applications of the prior art, and uses a hash function that is easy to calculate in consideration of the calculation capability of the tag And retrieval of tags in the database, and there is a resynchronization function that can be recovered and used again even if the session is disconnected by an attacker, and it is different in that it is designed to minimize the calculation amount in consideration of server or tag calculation ability. .

Also in the prior art [7] T. Dimitriou, “A lightweight RFID protocol to protect against traceability and cloning attacks,” Security and Privacy for Emerging Areas in Communications Networks-2005. SecureComm 2005, pp. 59-66, Sept., 2005 (hereinafter, only document numbers are described in the literature information of the prior art). However, this suggests an effective RFID authentication system, but it is weak in location tracking attack and cannot use tags if the session is not completed even once. On the contrary, the present invention can be authenticated by resynchronizing in the next session even if the session is unstable in the previous communication phase or there is an intentional attack, it can defend the location tracking attack, and can prevent most existing attacks In addition, the calculation amount of the tag or the server is improved, and thus the feature is improved.

As described above, the prior arts in the RFID system have a weakness such as a spoofing attack, a location tracking attack, or a resynchronization vulnerability. Another problem is that it takes a long time to find an ID in a database system.

Accordingly, the present invention has been proposed to solve the above-mentioned conventional problems, and an object of the present invention is to effectively resynchronize when the synchronization is off while preventing all attacks applied to the RFID system, and to reduce the amount of calculation of the DB. The present invention provides a mutual authentication device having low load and resynchronization characteristics and a method for a secure RFID system capable of presenting a tag authentication system of RFID.

In order to achieve the above object, a mutual authentication device having a low load and resynchronization characteristics for a secure RFID system according to an embodiment of the present invention,

In response to a request from an RFID reader According to the value or RFID tag for transmitting; A random number generated by generating a random number and a request are transmitted to the RFID tag, and two hash values received from the RFID tag and a random number generated by the RFID tag RFID reader for transmitting to the backend database; Two hash values and the random number generated by the RFID tag from the RFID reader Is received, and the unique identification information of the RFID tag for the management of the RFID tag , The hashed value of And the tag used in the previous session sign Has a field and receives from the RFID tag or Value , Compares the values in the field to the current session according to the state of the previous session. For the last session The back-end database to find; is made, including the features of the technical configuration.

In order to achieve the above object, a mutual authentication method having low load and resynchronization characteristics for a secure RFID system according to an embodiment of the present invention,

Selecting a random number from the RFID reader and transmitting the random number to the RFID tag with the request; After the first step, the RFID tag is a random number Select Depending on the value of Calculate differently, By calculating Value is 1, in response to the request , And Transmitting a second message to the RFID reader; After the second step, the RFID reader is a message received from the RFID tag. , And Random number And forwarding it to a backend database; After the third step, the backend database receives Depending on the value of For authentication of the RFID tag Wow And calculate Calculate and send to the RFID reader Updating the fourth step; After the fourth step, the RFID reader receives from the backend database. Transmitting a RFID tag to the RFID tag; After the fifth step, the RFID tag is calculated in the second step. Using the value Including the sixth step of verifying the accuracy of the performance of the technical configuration.

Hereinafter, an embodiment of the present invention as described above, a mutual authentication device having a low load and a resynchronization characteristic for a secure RFID system, and a method thereof will be described with reference to the accompanying drawings.

First, a mutual authentication device having a low load and a resynchronization characteristic for a secure RFID system according to an embodiment of the present invention, in response to a request of the RFID reader 20 According to the value or RFID tag 10 for transmitting the; A random number generated by generating a random number and a request are transmitted to the RFID tag 10, two hash values received from the RFID tag 10, and a random number generated by the RFID tag 10. RFID reader 20 for transmitting the to back-end database 30; Two hash values and the random number generated by the RFID tag 10 from the RFID reader 20 Is received, and the unique identification information of the RFID tag 10 for the management of the RFID tag 10 , The hashed value of And the tag used in the previous session sign Has a field and receives from the RFID tag 10 or Value , Compares the values in the field to the current session according to the state of the previous session. For the last session It characterized in that it comprises a; back-end database (30) to find.

When the tag does not receive the last message of the protocol due to a system communication failure or malicious attack, the RFID tag 10 Becomes 1 and the response value of the next session , Or if the normal authentication protocol is complete The value is 0 and is the response value of the request from the RFID reader 20 of the next session. It characterized in that for transmitting.

The RFID reader 20 transmits an authentication result message received from the backend database 30 to the RFID tag 10 when the backend database 30 has completed authentication with respect to the RFID tag 10. It is characterized by performing further including.

The back-end database 30, after authenticating the RFID tag 10 of the RFID tag 10 And further comprising transmitting a response message for authenticating itself.

Meanwhile, a mutual authentication method having low load and resynchronization characteristics for a secure RFID system according to an embodiment of the present invention includes selecting a random number from the RFID reader 20 and transmitting the random number to the RFID tag 10 with a request. Step 1; After the first step, the RFID tag 10 is a random number. Select Depending on the value of Calculate differently, By calculating Value is 1, in response to the request , And Transmitting a second message to the RFID reader 20; After the second step, the RFID reader 20 is a message received from the RFID tag 10. , And Random number And a third step of delivering to the backend database 30; After the third step, the backend database 30 receives Depending on the value of For authentication of the RFID tag 10 Wow And calculate Calculate and transmit to the RFID reader 20 Updating the fourth step; After the fourth step, the RFID reader 20 receives the data from the backend database 30. Transmitting the RFID tag to the RFID tag; After the fifth step, the RFID tag 10 is calculated in the second step. Using the value The sixth step of verifying the accuracy of the; characterized in that to perform.

The second step, If the value of is 1 , Otherwise It is characterized by that.

The fourth step, received from the back-end database 30 Value Compares to the values in the field, if a match is found Of tags for which An eleventh step to be to; characterized in that to perform.

The eleventh step is that if it is unable to find a matching value, And the values in the backend database 30 field. Computed and received the value Matches the value of, matches The value corresponding to the value of the tag 12th step to be to; characterized in that to perform.

The twelfth step, If not found, tag in previous session For With received Using Calculate the resulting value Sent from Requesting authentication by checking the value of of The thirteenth step of finding; characterized in that it comprises.

The sixth step, Calculated in the second step to verify the accuracy of the Use the value to verify that you pass the following equation,

When the equation passes, the RFID tag 10 transmits its own identification information. Renew with Is set to 0.

A preferred embodiment of a mutual authentication device having a low load and a resynchronization characteristic and a method for a secure RFID system according to the present invention configured as described above will be described in detail with reference to the accompanying drawings. In the following description of the present invention, when it is determined that a detailed description of related known functions or configurations may unnecessarily make the gist of the present invention unnecessary, the detailed description thereof will be omitted. In addition, terms to be described below are terms defined in consideration of functions in the present invention, which may vary according to intention or precedent of a user or an operator, and thus, the meaning of each term should be interpreted based on the contents throughout the present specification. will be.

First, the present invention is to provide an effective RFID tag authentication system that can be resynchronized when the synchronization is off while preventing all attacks applied to the RFID system, and also reduces the amount of DB calculation.

Thus, the present invention proposes an efficient protocol for reducing the computational load on tags and databases. The proposed protocol ensures location tracking, mutual authentication between the database and tags, and is secure against replay attacks, spoofing attacks, and asynchronous attacks. In particular, synchronization can be easily recovered even when asynchronous state between the database and the tag occurs due to communication failure or malicious attack.

Hereinafter, first, the security requirements for the components of the RFID system and the secure RFID system are defined, and the problems with the technology of the conventional authentication protocol research are analyzed. In addition, we will propose an efficient mutual authentication for RFID system and analyze the stability and efficiency.

1. RFID system

1-1) Components

1-1-1) RFID Tag

RFID tags generally consist of microchips for computation and data storage and antennas for wireless communication. It is divided into active and passive tags according to the power operation method. In other words, the active tag has a battery attached to the board, while the passive tag has no built-in battery, so it receives power from radio waves transmitted from the reader.

1-1-2) RFID Reader

The RFID reader serves as an intermediary that sends a query signal to the tag through the air interface, transmits information received from the tag to the database, and transmits the authentication result transmitted from the database back to the tag. The channel from the reader to the tag is defined as the forward channel, while the channel from the tag to the reader is defined as the backward channel, all of which are based on wireless communication, which is not secure to attackers. Is not a channel.

1-1-3) Backend Database

The backend database is responsible for the authentication of the tag based on the information received from the reader. After authentication, the backend database sends service information about the tag such as product description and price to the reader. The channel between the database and the reader is usually defined as a secure channel.

1-2) Security Requirements

For a secure RFID system, the following attacks must be robust ([1] to [3]).

1-2-1) Eavesdropping

Wireless communication between the reader and the tag could allow an attacker to eavesdrop on messages. Based on the eavesdropping, an attacker can attempt a replay attack, a spoofing attack, or find a useful or secret value in a tag. Therefore, RFID system should be designed to be robust against message leakage by wireless communication.

1-2-2) Spoofing Attack

The attacker collects the response mesh from the tag by sending a malicious query to the target tag. It sends a query to the tag by impersonating the correct reader and participates in the authentication protocol based on the information collected by the tag to make an illegal authentication attempt. Therefore, RFID system should be designed in consideration of this spoofing attack.

1-2-3) Location Tracking

Location tracking allows an attacker to know the tag owner's movement path by locating the tag, which can invade the owner's privacy. To prevent this location tracking, two security elements are defined. The first is indistinguishability, which indicates that it is difficult for an attacker to distinguish between a message sent by one tag and a message from another. Second, forward security defines that even if the secret data stored in the tag is exposed, the attacker cannot use it to track the location of the previous tag.

4) Desynchronization Attack

Asynchronous between the database and the tag is the result of a system communication failure or malicious attack This can happen when the update is not successful. If stuck in an asynchronous state, normal authentication cannot be possible and the position of the tag can be tracked, so the RFID system must be able to resynchronize quickly when asynchronous occurs.

2. Analysis of existing research on RFID certification

2-1) ID Variant Protocol

The ID modification protocol is proposed by Henriki and Muller, and is characterized by the change of the tag in every session ([4]). This allows a spoofing attack that is safe against replay attacks but allows a malicious attacker to approach the tag while pretending to be the correct leader. In other words. Collected from tags And Use to participate in the next certification process. In response to a query from a normal reader, you can pass the authentication process by sending these collected messages. Also, if an attacker intentionally blocks the last message in the protocol, the tag will not receive that message and will be considered as an authentication failure. Do not update. Therefore, in the next authentication session, the tag transmits the same message value as the previous session. This could allow an attacker to track the location of the tag.

2-2) Application-Response Based Authentication Protocol

Rhee et al. Proposed a Challenge-Response protocol based on a hash function ([5]). Their protocols are robust against spoofing and replay attacks and ensure location tracking. However, their scheme is inefficient in terms of computation. In other words, the back-end database stores all the data stored in the database to find the specific tag that requested authentication. It uses a pre-exploration method to compare values and perform hash operations. Although hash operations require a relatively small amount of computation compared to other cryptographic operations, it can be a significant burden for RFID systems that require fast authentication. How many tags the database manages and stores Of the particular tag that requested authentication Database to find Hash operation must be performed.

2-3) Low Cost Authentication Protocol: LCAP

The low cost authentication protocol (LCAP), proposed by Lee et al., Is relatively efficient because it requires only two hash operations in the tag ([6]). But in terms of stability, their schemes are vulnerable to location tracking. In other words, if the last message in the protocol is blocked by a communication failure or malicious attack, the tag Send the same message value as the previous session to the next authentication session without updating it. Thus, an attacker can identify the owner of a tag with persistent message blocking. Especially, Update method is It does not satisfy forward security because it consists of XOR (exclusive logic sum) with and the random number that is disclosed.

2-4) Lightweight Application-Response Protocols

Recently, Dimitriou has proposed a lightweight RFID authentication protocol ([7]). Their scheme is robust to location tracking prevention and tag duplication by sharing the secret with the database that is updated every session. However, if a malicious attacker blocks the last message in the protocol and the tag cannot receive the message, the tag and the database are asynchronous. In other words, the database On the other hand, the tag is Even in the next session without updating Will be used as is. The attacker could continue blocking, leaving both objects in an asynchronous deadlock and tracking the location of the tag.

3. Authentication protocol proposed by the present invention

This article describes an RFID system that is efficient, ensures mutual authentication, and can quickly resynchronize when an asynchronous condition occurs. First, terms used in the present invention are defined.

3-1) Definition of terms

RFID Tags

RFID Reader

: Backend Database

: The unique identification of the tag, bits

: The hashed value of, bits

: The tag used in the previous session , bits

: Random number generated by leader

: Random number generated by tag

: Request generated by reader

: Wow To check whether the update was successful at the same time

: One-way hash function,

: Input message Left half of

: Input message Right half of

: Concatenation of Two Input Messages

: Comparison of Two Input Information

3-2) System Models and Assumptions

2 is a view showing a mutual authentication device having low load and resynchronization characteristics and a method for a secure RFID system according to an embodiment of the present invention.

3-2-1) RFID Tag

Is of In response to According to the value or Send it. That is, if the tag does not receive the last message of the protocol due to system communication failure or malicious attack, Becomes 1 and the response value of the next session Send it. On the other hand, if the normal authentication protocol is completed The value is 0, and the value of the next session From As the response value of Send it.

3-2-2) RFID Reader

Is a random number generated by itself with To Broadcast to and in response The two hash values received from To It serves to deliver. end If you are certified for The authentication result message received from To pass.

3-2-3) Back-End Database

To manage each tag , And It has a field. Depending on the state of the previous session For the current session For the last session Can be found. this is Received from or Values in the database , This can be done by comparing the values in the field. After verifying Of the tag Send a response message to update and authenticate itself.

3-3) Protocol Description

2 shows a schematic process of the proposed mutual authentication protocol.

The detailed procedure of the proposed mutual authentication protocol is as follows.

i) Is a random number Select with Send to.

ii) Is a random number Select Depending on the value of Calculate differently. In other words, If the value of is 1, , Otherwise to be. Is Calculate Leave the value at 1. Is In response to , And To Send to.

iii) silver Messages received from, , And Generated in step i) with To pass.

iv) Received Depending on the value of Find it. first, Received Value Compare with the values in the field. If a matching value is found, that Of tags for which Becomes

On the other hand, if no match is found, the second search Received Wow Using the values in the field Computed and received the value Compare with the value of. At this time The value corresponding to the value of the tag Becomes In this case, of For Reply message caused by an attacker's message blocking , , end Occurs when it cannot be sent to. That is, in the previous session Wow Not all of them pass the certification Failed to update the value The value is one.

Even in the second case above If you don't find Is the third step in the search process. Equivalent to With received Using Calculate the resulting value Sent from Requesting authentication by checking the value of of Will be found. In this case, About the Second sent message In the previous session due to the attacker's message blocking Is Update the value, Does not pass the certification process Failed to update the value The value is one.

of or Found To authenticate the tag Wow Calculate and verify that the following equation 1 holds.

here, Is The value received from. If Equation 1 is satisfied, Is By calculating To Update In other words, Computed, and then updated Uniquely identifying information for to be.

v) silver Received from of To pass.

vi) To verify the accuracy of Is calculated in step ii) Use the value to check whether the following equation (2) passes.

If Equation 2 passes Has its own unique identifying information Renew with Set to 0.

4. Analysis

4-1) Stability

This paper analyzes whether the proposed mutual authentication protocol satisfies the RFID system security requirements. Table 3 shows the results of the analysis.

4-1-1) eavesdropping

In order to gain the confidential information of an attacker, an attacker of Should be restored. In other words, or Attacker from the We have to guess, but this is not possible due to the unidirectional nature of the hash function. Attacker known or Suitable for An attack can be performed that calculates, but this is also not possible due to the one-way nature of the hash function. On the other hand, every session Is updated, so replay attack is impossible. Therefore, the proposed mutual authentication protocol is robust against attack by attacker's eavesdropping.

4-1-2) Spoofing Attack

Attacker is correct Pretending After collecting response messages from, Pretends to pass the certification process. However, of Without knowing the value, Wow It is not possible to compute 으로 due to the unidirectionality of the hash function. Therefore, the proposed protocol is safe against spoofing attacks.

4-1-3) Location Tracking

The proposed protocol is for each session Since the value is updated Location privacy is guaranteed. That is, it satisfies indistinguishability and forward security. Assume that successful authentication was performed in the previous session. To authenticate the current session Is In response to Send the value. At this time Is the updated value due to successful authentication of the previous session. Has a different value from the hash result of the previous session. On the other hand, if the protocol is abnormally completed due to a communication failure or malicious message blocking by an attacker, Is In response to Send it. Although Is not updated Since a hash value containing is transmitted, a hash value different from the response of the previous session is transmitted. That is, it satisfies the indistinguishability regardless of the normal / abnormal authentication result of the protocol.

The proposed protocol end As it is composed of the form, it satisfies forward security. In other words, Is exposed before For The value cannot be restored. This is due to the one-sided nature of the hash function.

4-1-4) Desynchronization Attack

If a malicious attacker interfered with the normal authentication process due to message blocking, Wow Can be asynchronous. That is, deliberately disconnecting the second response message from the protocol. If you block messages that are forwarded to Wow Are all The update will fail. During the authentication process for the next session Is Even if you send Is Through the field Find the value and perform an update later. On the other hand, the attacker is the last step in the protocol If you have blocked a message sent to Is Perform the update Is not. In this case, asynchronous occurs but the authentication of the next session Is Through the field It is easy to find the value and then resync. Therefore, the proposed protocol is robust against asynchronous attacks.

4-2) Efficiency

In order to analyze the degree of efficiency of the proposed protocol, we compare the amount of computation with the previous studies. That is, the table of FIG. Wow The amount of computation at is compared with the existing study. If the proposed protocol is successfully completed, Wow Performs three hash operations each. But in asynchronous state It requires one hash operation. This is Rhee's protocol for authentication It is quite efficient compared to the need for a single hash operation.

Is For storing Bit and 1 bit for total It requires a bit of storage space. On the other hand, end doggy Assuming you manage Is Requires storage space. In addition, this protocol is designed considering the amount of communication on the wireless channel. In other words, to reduce the traffic Is And send silver Send it. therefore in The traffic sent to ego, in The traffic sent to to be. Therefore, the proposed mutual authentication protocol is suitable and practical for RFID system with limited memory space.

5. Conclusion

The present invention proposes an efficient and practical mutual authentication protocol while satisfying the security requirements of the RFID system. The tag owner's location privacy is guaranteed and robust to replay attacks, spoofing attacks, and asynchronous attacks. In particular, even when the authentication process is abnormally terminated by a communication failure or malicious attack, synchronous recovery between tags and the database is possible.

As described above, the present invention provides an effective RFID tag authentication system that can resynchronize when the synchronization is off while preventing all attacks applied to the RFID system, and also reduces the DB calculation amount.

As described above, the mutual authentication device having a low load and resynchronization characteristics and a method for a secure RFID system according to the present invention may be resynchronized when the synchronization is off while preventing all attacks applied to the RFID system. It is possible to present an effective RFID tag authentication system that also reduces the amount of computation of the DB.

Although the above has been described as being limited to the preferred embodiment of the present invention, the present invention is not limited thereto and various changes, modifications, and equivalents may be used. Therefore, the present invention can be applied by appropriately modifying the above embodiments, it will be obvious that such application also belongs to the scope of the present invention based on the technical idea described in the claims below.

Claims (10)

In response to a request from an RFID reader According to the value or RFID tag for transmitting; A random number generated by generating a random number and a request are transmitted to the RFID tag, and two hash values received from the RFID tag and a random number generated by the RFID tag RFID reader for transmitting to the backend database; Two hash values and the random number generated by the RFID tag from the RFID reader Is received, and the unique identification information of the RFID tag for the management of the RFID tag , The hashed value of And the tag used in the previous session sign Has a field and receives from the RFID tag or Value , Compares the values in the field to the current session according to the state of the previous session. For the last session A back-end database for finding a mutual authentication device having a low load and resynchronization characteristics for a secure RFID system, comprising a. The method according to claim 1, wherein the RFID tag, If the tag does not receive the last message in the protocol due to a system communication failure or malicious attack, etc. Becomes 1 and the response value of the next session , Or if the normal authentication protocol is complete The value is zero and the response value of the request from the RFID reader of the next session. A mutual authentication device having low load and resynchronization characteristics for a secure RFID system, characterized in that for transmitting a. The method according to claim 1, wherein the RFID reader, Low load and resynchronization characteristics for a secure RFID system, if the back-end database has completed the authentication for the RFID tag, further comprising transmitting an authentication result message received from the back-end database to the RFID tag Mutual authentication device with. The system of claim 1, wherein the backend database is After authenticating the RFID tag, And a load message and a resynchronization characteristic for a secure RFID system, further comprising transmitting a response message for authenticating and authenticating itself. Selecting a random number from the RFID reader and transmitting the random number to the RFID tag with the request; After the first step, the RFID tag is a random number Select Depending on the value of Calculate differently, By calculating Value is 1, in response to the request , And Transmitting a second message to the RFID reader; After the second step, the RFID reader is a message received from the RFID tag. , And Random number And forwarding it to a backend database; After the third step, the backend database receives Depending on the value of For authentication of the RFID tag Wow And calculate Calculate and send to the RFID reader Updating the fourth step; After the fourth step the RFID reader has received from the backend database Transmitting a RFID tag to the RFID tag; After the fifth step, the RFID tag is calculated in the second step. Using the value A sixth step of verifying the accuracy of the; mutual authentication method having a low load and resynchronization characteristics for a secure RFID system comprising a. The method of claim 5, wherein the second step, If the value of is 1 , Otherwise A mutual authentication method with low load and resynchronization characteristics for a secure RFID system, characterized in that. The method of claim 5, wherein the fourth step, Received from the backend database Value Compares to the values in the field, if a match is found Of tags for which The eleventh step to be a; mutual authentication method having a low load and re-synchronization characteristics for a secure RFID system comprising a. The method of claim 7, wherein the eleventh step, If no match is found, the received And the values in the backend database fields Computed and received the value Matches the value of, matches The value corresponding to the value of the tag A twelfth step to be a; mutual authentication method having a low load and resynchronization characteristics for a secure RFID system comprising a. The method according to claim 8, wherein the twelfth step, If not found, tag in previous session Equivalent to With received Using Calculate the resulting value Sent from Requesting authentication by checking the value of of The 13th step of finding a; mutual authentication method having a low load and resynchronization characteristics for a secure RFID system comprising a. The method according to any one of claims 5 to 9, wherein the sixth step is Calculated in the second step to verify the accuracy of the Use the value to verify that you pass the following equation, When the equation passes, the RFID tag sends its own identification information. Renew with A method of mutual authentication with low load and resynchronization characteristics for a secure RFID system, characterized by setting zero to zero.