KR20200039190A - Method for Authenticating Multiple Sender Transmitting Image Data - Google Patents

Abstract

According to one embodiment of the present invention, a method of authenticating multiple transmission sources transmitting image data, which can authenticate a plurality of transmission sources transmitting image data, includes the steps of: allowing at least one reception source and a plurality of transmission sources to create a secret key table comprising n secret keys; allowing the reception source or transmission sources to create a session key and a secret key selection identifier for deriving the session key by using at least one target secret key selected from the secret key table; allowing the transmission sources to create a valid message authentication code (MAC) for the authentication of the transmission sources and the verification of the integrity of image data by inputting the session key and the image data which becomes a transmission target into a preset hash function; allowing the transmission sources to create transmission data by merging the image data, the secret key selection identifier and the valid MAC to transmit the transmission data to the reception source.

Description

Method for Authenticating Multiple Sender Transmitting Image Data}

The present invention relates to device authentication, and more particularly, to authentication of a transmission source transmitting image data.

In a communication system, a method of calculating and attaching a message authentication code (MAC: Message Authentication Code, hereinafter referred to as 'MAC') to a data packet to be transmitted is used for authentication of a source transmitting data and verification of integrity of transmitted data. . At this time, the MAC may be calculated using an HMAC function or a public key-based digital signature.

Because the public key-based digital signature requires higher computation than HMAC, it is not suitable for data that requires real-time transmission due to latency required for signature generation and verification, and high hardware resources (high-performance CPU, memory space). . Therefore, in the case of data requiring real-time transmission, the HMAC function, which is a secret key based hash function, is mainly used.

When the HMAC function is applied, the MAC is created by inputting a message and a secret key to the hash function. Therefore, the subject who does not own the secret key cannot generate the MAC and cannot verify the MAC.

1 shows a method of calculating a MAC using the secret key-based hash function, HMAC, and transmitting the calculated MAC by adding it to the data. As shown in FIG. 1, a sender enters a secret key and a message that is shared secretly with a receiver in the HMAC function to calculate the MAC, and adds the calculated MAC to data as a recipient. send.

The receiver calculates the HMAC result by providing the secret key shared secretly with the sender and the message received from the sender as input to the same HMAC function. The receiver compares the calculated HMAC result value with the MAC sent by the sender and authenticates the message transmission and message integrity in the same case.

However, when the HMAC method as described above is applied to a communication environment in which a time characteristic is required and a source and a receiver have an n: 1 relationship, the source must not only have different secret keys as many as the number of receivers, In order to send a message to each receiver, the sender must calculate HMAC as many as the number of receivers, so there is a problem that it is difficult to apply to a source with limited resources (such as CPU or memory) such as a drone or CCTV.

To solve this, not only does the problem that security can be lowered if the sender uses the same secret key for all receivers, but also because the secret key must be changed in a certain time unit, resources such as drones or CCTVs are limited. There is a problem that it is difficult to apply to the source.

The present invention is to solve the above-mentioned problems, and its technical problem is to provide an apparatus and method capable of authenticating a plurality of transmission sources for transmitting image data.

Another object of the present invention is to provide a multi-source authentication apparatus and method for transmitting image data capable of generating a secret key to be used for MAC generation using a secret key table shared between a sender and a receiver.

A multi-source authentication method for transmitting image data according to an aspect of the present invention for achieving the above object comprises: generating a secret key table in which one receiver and a plurality of transmitters are composed of n secret keys; Generating a session key and a secret key selection identifier for deriving the session key by using the at least one target secret key selected by the receiver or the sender on the secret key table; Generating a message authentication code (MAC) for verifying the integrity of the image data and authenticating the source by using the session key and the transmission key as the input of a predetermined hash function. ; And generating, by the transmitting source, transmission data combining the video data, the secret key selection identifier, and the effective MAC, and transmitting the transmitted data to the receiving source.

An image data transmitting and receiving device authentication method according to another aspect of the present invention for achieving the above object comprises the steps of: a first device and a second device sharing a secret key table consisting of n secret keys; The first device generates a session key for calculating a message authentication code (MAC) and a secret key selection identifier for deriving the session key using at least one target secret key selected from the secret key table. To do; The first device transmitting the secret key selection identifier to the second device; And calculating, by the second device, the MAC by deriving the session key using the secret key selection identifier.

According to the present invention, it is possible to authenticate a plurality of video data transmission sources with limited available resources, such as a drone or a CCTV, without increasing the load, so that the video data can be received only from a transmission source having a legitimate authority.

In addition, according to the present invention, since each sender can generate different secret keys using a single secret key table, not only security is improved, but also a new secret key needs to be generated and shared with the receiver by a certain time unit. There is no effect that there is no available resource to reduce the burden on the limited source.

In addition, according to the present invention, since a secret key is generated using a secret key table, there is an effect that more secret keys can be generated compared to a method of generating a secret key using a hash chain.

1 is a view showing a method of transmitting by adding a MAC calculated using the secret key-based hash function HMAC method to the data.
FIG. 2 is a diagram showing a network configuration to which a multi-source authentication method for transmitting image data according to an embodiment of the present invention is applied.
3 is a flowchart showing a multi-source authentication method for transmitting image data according to an embodiment of the present invention.
4 is a flowchart showing a method of generating a secret key table by a sender and a receiver.
5 is a view showing an example of a secret key table according to the present invention.
6 is a diagram conceptually illustrating a method of generating a session key according to an embodiment of the present invention.
7 is a diagram conceptually explaining a method in which a sender changes a session key.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The meaning of the terms described in this specification should be understood as follows.

It should be understood that a singular expression includes a plurality of expressions unless the context clearly defines otherwise, and the terms "first", "second", etc. are intended to distinguish one component from another component, The scope of rights should not be limited by these terms.

It should be understood that terms such as “include” or “have” do not preclude the presence or addition possibility of one or more other features or numbers, steps, actions, components, parts or combinations thereof.

It should be understood that the term “at least one” includes all possible combinations from one or more related items. For example, the meaning of “at least one of the first item, the second item, and the third item” means 2 of the first item, the second item, and the third item, as well as each of the first item, the second item, and the third item. Any combination of items that can be presented from more than one dog.

FIG. 2 is a diagram showing a network configuration to which a multi-source authentication method for transmitting image data according to an embodiment of the present invention is applied.

As shown in FIG. 2, the multi-transmission source authentication method for transmitting image data according to an embodiment of the present invention is transmitted through various types of networks from n transmission sources 210a to 210n and n transmission sources generating image data. It can be applied to a communication system consisting of one receiving source 220 for receiving image data.

In one embodiment, the n transmission sources 210a to 210n may be drones or CCTV cameras that generate image data, and the receiver 220 receives image data from a drone or CCTV camera to display devices ( It may be a controller (GCS) or a control center output through the (225).

In FIG. 2, the present invention has been described as being applied to a communication system consisting of n transmission sources 210a to 210n and one reception source 220, but the present invention is not limited to this, and one transmission source S and n reception It may be applied to a communication system composed of circles (R1 to Rn). For example, this may be the case when multiple controllers or control centers receive images captured by one drone or multiple controllers or control centers receive images captured by one CCTV camera.

Hereinafter, a method of authenticating a multi-source that transmits image data according to the present invention will be described with reference to FIGS. 3 and 4.

3 is a flowchart showing a multi-source authentication method for transmitting image data according to an embodiment of the present invention.

As shown in FIG. 3, the sender 210a to 210n and the receiver 220 generate a secret key table composed of n secret keys (S300). At this time, the secret key in transmitting the image data generated by the transmitting source (210a ~ 210n) to the receiving source 220, the receiving source 220, the integrity of the corresponding image data and the transmitting source 210a ~ for transmitting the image data 210n).

Hereinafter, a method of generating a secret key table according to the present invention will be described in more detail with reference to FIG. 4.

4 is a flowchart showing a method of generating a secret key table according to an embodiment of the present invention.

As illustrated in FIG. 4, the device registration device 230 illustrated in FIG. 2 authenticates and registers n transmission sources 210a to 210n (S400).

Subsequently, the security key generator 240 generates master keys for the transmitters 210a to 210n and the receiver 220 (S410), and the generated master keys are the transmitters 210a to 210n and the receiver 220 It is injected into (S420). In one embodiment, the size of the master key may be 128 bits.

2 and 4, although the device registration device 230 and the security key generation device 240 are shown as having separate configurations from the reception source 220, in another embodiment, the device registration device 230 and the security key generation The device 240 may be configured to be included in the receiving source 220.

Thereafter, the reception source 220 generates n secret keys (S425). First, the receiver 220 uses the seed information composed of the random number generated by the receiver 220 and the time information for generating the secret key table as input of a predetermined hash function 1 Obtain the second secret key. In one embodiment, the receiver 220 may use a SHA1 based HMAC algorithm as a hash function.

Subsequently, n secret keys are sequentially generated using a forward hash chain based on the first secret key obtained by the receiver 220. That is, the result value of Hash (random number ∥ time information) becomes the first secret key, and the result value of rehashing the first secret key becomes the second secret key. Accordingly, the result value of Hash (n-1st secret key) becomes the nth secret key. Here, the symbol "∥" means to merge data located in front and rear of "∥".

For example, assuming that the random number is 1234567890, the time information requested to generate the secret key table is 20180730121432, and the hash algorithm uses SHA1, and among the 160 bits generated from SHA1, 128 bits are used as the secret key. , The first hash result K1 is derived according to Equation 1 below.

Thereafter, the result of hashing the first secret key K1 again, K2, is derived according to Equation 2 below.

The receiving source 220 sequentially generates n secret keys using the forward hash chain as above.

Thereafter, the reception source 220 generates a secret key table using n secret keys generated in S425 (S430). An example of a secret key table composed of n secret keys generated through the above-described example is illustrated in FIG. 3. In FIG. 3, for convenience of explanation, the secret key table is shown to be composed of seven secret keys, but this is only an example, and the secret key table may be composed of eight or more secret keys.

Subsequently, the receiving source 220 generates a secret key table creation request message to allow the transmitting sources 210a to 210n to generate the same secret key table generated in S430 to the transmitting sources 210a to 210n. Transmit (S440).

In one embodiment, the secret key table generation request message includes a message type identifier indicating the type of the message, identification information of the receiver 220, and an encryption value.

At this time, the message type identifier is for identifying the type of the corresponding message. For example, the message type identifier may be composed of 2 bits. For example, if the value of the message type identifier is "00", it indicates that the message is a message requesting the generation of the secret key table. If the value of the message type identifier is "01", the message is sent to the request to generate the secret key table. Response message, and if the value of the message type identifier is "10", it indicates that the message is a request for reconfiguration of the secret key table, and when the value of the message type identifier is "11", the message is reconstructed. Indicates that it is a response message to the request.

In the above-described embodiment, it has been described that the message type identifier is composed of 2 bits, but this is only an example, and the number of bits constituting the message type identifier may be changed as the message type increases or decreases.

On the other hand, the identification information of the receiver 220 included in the secret key table generation request message is for identifying the receiver 220 that has transmitted the message, and the receiver 220 is transmitted by the transmitters 210a to 210n. Used when authenticated.

In addition, the encryption value included in the secret key table generation request message includes identification information of the receiver 220, information about a hash function used by the receiver 220 to generate the secret key, and the receiver 220 generates the secret key table. Seed information used in and the number of secret keys to be included in the secret key table means a result of cryptographic conversion as a master key. In one embodiment, the encryption value included in the secret key table generation request message may further include an effective time of the secret key table.

When the secret key table generation request message is received from the reception source 220, the transmission sources 210a to 210n decrypt the encryption value included in the received secret key table generation request message with a master key (S450). Subsequently, the transmitting sources 210a to 210n compare the identification information of the receiving source 220 decoded in S450 with the identification information of the receiving source 220 included in the secret key table generation request message, and the receiving source 220 legally receives the received information. Whether it is a circle 220 is authenticated (S460).

Specifically, when it is determined that the identification information of the reception source 220 decoded in S450 is the same as the identification information of the reception source 220 included in the secret key table generation request message, the transmission sources 210a to 210n receive source 220 ) Authenticates that the receiver 220 is a legitimate receiver by determining that it has the same master key as itself.

If the transmission sources 210a to 210n determine that the identification information of the reception source 220 decoded in S450 is not the same as the identification information of the reception source 220 included in the secret key table generation request message, the reception source 220 The procedure is terminated by determining that it is an illegal recipient that does not have the same master key.

When the authentication result of S460, the receiving source 220 is authenticated as a legitimate receiving source 220, the transmitting sources 210a to 210n generate n secret keys using the values decoded in S450 (S465). First, the transmitters 210a to 210n acquire the first secret key by using the random number and time information included in the seed information decoded in S450 as inputs of the hash function decoded in S450. Thereafter, the transmission sources 210a to 210n generate n secret keys using a forward hash chain based on the first secret key.

Specifically, the result value of Hash (random number ∥ time information) becomes the first secret key, and the result value of rehashing the first secret key becomes the second secret key. Accordingly, the result value of Hash (n-1st secret key) becomes the nth secret key. According to this process, the transmitting sources 210a to 210n and the receiving source 220 share the same n secret keys with each other.

Meanwhile, the transmission sources 210a to 210n generate a secret key table using n secret keys generated in S465 (S470). As described above, since the generation of the secret key table is completed, the transmission sources 210a to 210n also share the same secret key table as the reception source 220.

When the generation of the secret key table is completed, the transmission sources 210a to 210n generate a secret key table generation response message and transmit it to the reception source 220 (S475). In one embodiment, the secret key table generation response message includes a message identification code, identification information of the senders 210a to 210n transmitting the corresponding message, and a test MAC. At this time, the message identification code may be set to "01" because the corresponding message is a secret key table creation response message.

On the other hand, the test MAC is a test message obtained by subtracting a predetermined value (for example, 1) from the number of secret keys generated in S465 and a test message in which identifiers of the corresponding senders 210a to 210n are merged and a secret key table generated in S470. It can be obtained by assigning the Nth secret key of as an input to the hash function. Since these test MACs can be calculated and verified only by the transmitters 210a to 210n and the receivers 220 having the same secret key table, the transmitters 210a to 210n can be used to calculate and verify the test MAC. The receiver 220 can authenticate each other.

Thereafter, when the secret key table generation response message is received from the transmission sources 210a to 210n, the reception source 220 calculates and verifies the test MAC included in the secret key table generation response message using the secret key table generated in S430. (S480). Specifically, the receiving source 220 is a value obtained by subtracting a predetermined number from the Nth secret key on the secret key table generated in S430, the identification information of the transmitting sources 210a to 210n received in S475, and the number of secret keys. Calculate the test MAC using. The receiver 220 compares the calculated test MAC with the test MAC received at S475, so that it is possible to verify that the sender 210a-210n generated the secret key table as well as the authentication of the sender 210a-210n. do.

Thereafter, the receiver 220 generates a session key for calculating the effective MAC of the image data to be actually transmitted (S490), and generates a secret key selection identifier for deriving the generated session key (S492). Here, the session key refers to a secret key to be used for effective MAC calculation of actual video data, and two or more secret keys (hereinafter referred to as 'target secret keys') among a plurality of secret keys included in the secret key table. Can be created by combining. For example, the session key may be generated by combining two target secret keys on the secret key table.

In accordance with this embodiment, the secret key selection identifier may be expressed as Equation 3 below.

In Equation 3, Kinfo means a secret key selection identifier, KU_F means a first identifier indicating whether to maintain or change the previously generated session key, and i is the identification number of the first target secret key to be used to generate the session key. Denotes, j denotes the identification number of the second target secret key to be used for generating the session key, k denotes the number of bits to be used for generating the session key among the bits of the first and second target secret keys, and ∥ It means the merging of each data.

At this time, the first identifier KU_F may be set to "0" when maintenance of the previously generated session key is required, and may be set to "1" when change of the session key is required. When the first identifier KU_F is set to 0, since there is no change of the session key, i representing the identification number of the first target secret key, j representing the identification number of the second target secret key, and session key generation All k representing the number of bits to be used are set to zero.

A method in which the receiver 220 generates a session key using two target secret keys will be described in detail with reference to FIG. 6.

6 is a diagram conceptually showing a method of generating a session key according to an embodiment of the present invention. 6, the session key SKi may be generated by combining the first target secret key Ki and the second target secret key Kj. Specifically, the session key is a result of XORing the back k bits (B) of the bits of the first target secret key (Ki) and the front k bits (C) of the bits of the second target secret key (Kj) ( E) is calculated by merging the first target secret key (Ki) with the rear end of the remaining front bits (A) except for the rear k bits (B).

As described above, according to the present invention, by combining a plurality of target secret keys on the secret key table, the number of available session keys is increased because the session keys for valid MAC calculation of actual image data can be derived. 210a to 210n) and the receiving source 220 do not need to directly store a large number of session keys, and thus the advantages of the present invention can be applied to the lightweight transmitting sources 210a to 210n and the receiving source 220 without resource limitation. .

Then, the receiver 220 calculates the initial MAC obtained by using the secret key selection identifier generated in S492 and the N-1th secret key on the secret key table as the input of the hash function (S494), and the message identification code, A secret key table generation end message including the initial MAC calculated in S494 and the secret key selection identifier is generated and transmitted to the transmitting sources 210a to 210n (S496). At this time, the message identification code may be set to "01" and the first identifier (KU_F) in the secret key selection identifier may be set to "0".

Thereafter, the transmitters 210a to 210n verify the initial MAC received in S496 using the secret key selection identifier received in S496 and the N-1th secret key on the secret key table (S498), and the verification result shows a normal initial MAC. If it is determined to be, a session key to be used for actual image data transmission is generated based on the secret key selection identifier received in S496 (S499).

Referring back to FIG. 3, the transmitters 210a to 210n generate valid MACs obtained by inputting the image data generated by the transmitters 210a to 210n and a session key to be applied to the image data as an input of a hash function (S310). ). In one embodiment, the session key used to generate a valid MAC in S310 may be generated by the secret key selection identifier received from the receiver 220 in the process of generating the secret key.

Hereinafter, a method of deriving a session key using the secret key selection identifier by the transmitting sources 210a to 210n will be described using the secret key table shown in FIG. 5 and the session key generation method shown in FIG. 6. First, assuming that the transmission sources 210a to 210n have received the secret key selection identifier having a value of [0, 3, 5, 16] from the reception source 220, since the value of the first identifier KU_F is "1" Since it means that the session key is newly set, the transmitters 210a to 210n load the third target secret key K3 and the fifth target secret key K5 on the secret key table.

In FIG. 5, K3 is "04e45d7bcabbde40b38dff2a19232782", and K5 is "43f13fc53bd58a9fe4368ed79a097a9e", so the transmitters 210a to 210n converted "2782", which is the lower 16 bits of K3 (B in FIG. 6) to binary number, "0010 0111 1000 0010 XOR operation of "0100 0011 1111 0001" in which "43f1", which is the upper 16 bits of "and K5" (C in FIG. 6) is converted to binary, obtains "0111 0100 0111 0011", and convert it back to hexadecimal. A result value (E in FIG. 6) of "64e3" is obtained. Subsequently, the transmitters 210a to 210n merge "04e45d7bcabbde40b38dff2a192364e3" by merging to the rear end of the remaining upper bits (A in FIG. 6) except the lower 16 bits (B in FIG. 6) among the bits of the first target secret key SK3. Calculate the session key (SKi) having the value of.

Thereafter, the transmitting sources 210a to 210n merge the image data generated by the transmitting sources 210a to 210n, a secret key selection identifier for generating a session key used for generating an effective MAC, and an effective MAC to the receiving source 220 The transmission data to be transmitted is generated (S330), and the generated transmission data is transmitted to the reception source 220.

On the other hand, although not shown in FIG. 3, when the receiving source 220 receives the transmission data, the receiving source 220 uses the secret key selection identifier included in the transmission data to calculate the MAC of the transmission data (S1 to Sn). The session key used is derived. Since the process of deriving the session key was described in FIG. 5, detailed description is omitted. The receiving source 220 authenticates the integrity of the image data included in the transmission data and the transmitting sources 210a to 210n by calculating the MAC using the derived session key.

In the above-described embodiment, it has been described that the transmitting sources 210a to 210n generate a session key based on the secret key selection identifier transmitted from the receiving source 220. However, in another embodiment, the transmitting sources 210a-210n do not generate a session key based on the secret key selection identifier transmitted from the receiving source 220, but instead generate a new session key directly or a predetermined event occurs. If it does, you can change the previously created session key.

In this case, the transmitters 210a to 210n set the value of the first identifier to "1", the identification number of the first target secret key used to generate the session key to be changed, the identification number of the second target secret key, and The secret key selection identifier including information on the number of bits of the session key is newly set, and the newly set secret key selection identifier is transmitted to the receiver 220.

The method in which the transmission sources 210a to 210n change the session key is illustrated in FIG. 7. As shown in FIG. 7, the transmitters 210a to 210n calculate the MAC using the first session key SK1 during the first period and the second period, and the second session key (the new session key during the third period) ( It indicates that MAC is calculated using SK2).

At this time, the transmission message transmitted from the transmitting source 210a to 210n to the receiving source 220 during the first period is composed of "D1∥Kinfo∥HMAC (D1, SK1)" as shown in FIG. The transmission message transmitted from the transmitting source 210a to 210n to the receiving source 220 is composed of "D2∥Kinfo∥HMAC (D2, SK1)", and the transmitting source 220 from the transmitting source 210a to 210n during the third period ) Is sent to "D3 ∥ Kinfo ∥ HMAC (D3, SK2)". At this time, since the session key has not been changed during the second period, the first identifier KU_F among the values of Kinfo is set to “0”. However, since the session key is newly changed in the third section, the first identifier KU_F among the values of Kinfo is set to “1”.

In FIG. 4, it has been described that the receiving source 220 requests the generating source 210a to 210n to generate the secret key table, but in another embodiment, the sending source 210a to 210n requests the receiving source 220 to generate the secret key. It might be.

In addition, in FIG. 3, before transmission of the actual image data, it has been described that the transmission sources 210a to 210n and the reception source 220 generate a secret key table, but the transmission sources 210a to 210n and The receiver 220 may also reconstruct the previously generated secret key table. The method of reconfiguring the secret key table is the same as that shown in FIG. 4, so a detailed description thereof will be omitted.

As described above, according to the present invention, the source 210a to 210n and the receiver 220 share a secret key table with each other and combine two or more secret keys selected on the secret key table to perform MAC calculation of image data. Since the generation of the session key for the transmission source (210a ~ 210n) and the reception source 220 does not need to have a large number of secret keys, respectively, time synchronization is not required to synchronize the secret keys held by each other Does not. In addition, according to the present invention, since n secret keys are generated using a forward hash chain, immediate processing is possible, thereby minimizing the delay generated when authenticating the source.

Those skilled in the art to which the present invention pertains will understand that the above-described present invention can be implemented in other specific forms without changing its technical spirit or essential features.

For example, the multi-source authentication method for transmitting the image data described in FIGS. 3 and 4 may be implemented in a program form such as an application or an agent and mounted on a medium capable of reading the corresponding program. When the multi-source authentication method for transmitting image data according to the present invention is implemented as a program, each step shown in FIGS. 3 and 4 is implemented as a code, and codes for implementing a specific function are implemented as a single program or , It may be implemented by dividing a plurality of programs.

When the present invention is implemented by being divided into a plurality of programs, each program may be mounted on different media. For example, a function performed at a transmission source may be mounted on a medium provided at the transmission source, and a function performed at a reception source may be mounted on a medium provided at the reception source.

In another embodiment, the multi-source authentication method for transmitting the image data described in FIGS. 3 and 4 may be implemented through a hardware device capable of implementing the method, or may be implemented by combining a program and hardware.

Therefore, it should be understood that the embodiments described above are illustrative in all respects and not restrictive. The scope of the present invention is indicated by the following claims rather than the above detailed description, and it should be interpreted that all changes or modifications derived from the meaning and scope of the claims and equivalent concepts are included in the scope of the present invention. do.

210a to 210n: source 220: source
230: device registration device 240: security key generation device

Claims (13)

Generating a secret key table composed of n secret keys by one reception source and a plurality of transmission sources;
Generating a session key and a secret key selection identifier for deriving the session key by using the at least one target secret key selected by the receiver or the sender on the secret key table;
Generating a message authentication code (MAC) for verifying the integrity of the image data and authenticating the source by using the session key and the transmission key as the input of a predetermined hash function. ; And
And generating, by the transmitting source, transmission data combining the video data, the secret key selection identifier, and the effective MAC, and transmitting the transmitted data to the receiving source. According to claim 1,
In the step of generating the secret key table,
The receiving source and the transmitting source are first secret based on the value obtained by inputting the hash function using seed information composed of the random number generated by the receiving source and the time information requested to generate the secret key table. A multi-source authentication method for transmitting image data, wherein the n secret keys are generated using a forward hash chain as a key, and the secret key table is generated using the n secret keys. According to claim 1,
The step of generating the secret key table,
A first result value encrypted by the receiving party with identification information of the receiving party, seed information for generating the secret key table, information about a hash function, and a number of the secret key with a master key that is previously shared with the transmitting source. Transmitting a request for generating a secret key table including identification information of the receiving source to the transmitting source;
Authenticating the receiving source by comparing the identification information of the receiving source obtained by decoding the first result value with the master key with the identification information of the receiving party included in the secret key table generation request; And
When the authentication of the receiver is successful, the sender generates the n secret keys using the seed information obtained by decoding the first result value as the input of the hash function, and uses the n secret keys to generate the secret keys. And generating a key table. According to claim 3,
The step of generating the secret key table,
When the sender generates the secret key table, a test message obtained by subtracting a predetermined value from the number of secret keys and an identifier of the sender and the Nth secret key on the secret key table of the hash function Transmitting the test MAC obtained as an input to the receiving source along with the identifier of the transmitting source; And
The receiver obtains identification information of the sender from the test MAC using the Nth secret key on the secret key table, compares the obtained identification information of the sender with the identification information of the sender received from the sender, and A method for authenticating multiple sources of transmitting image data, further comprising authenticating the source. According to claim 3,
A multi-source authentication method for transmitting image data, characterized in that the first result value encrypted with the master key further includes information on the valid time of the secret key table. According to claim 1,
The secret key selection identifier includes a first identifier indicating whether the session key is maintained or changed, an identification number of a first target secret key to be used to generate the session key, and an identification number of a second target secret key to be used to generate the session key. And a number of bits to be used to generate the session key among the bits of the first and second target secret keys. The method of claim 6,
When the maintenance of the session key is determined, the value of the first identifier, the identification number of the first target secret key, the identification number of the second target secret key, and the number of bits to be used for generating the session key are set to 0. A multi-source authentication method for transmitting video data. According to claim 1,
The target secret key is composed of a first target secret key and a second target secret key,
The session key is a result of XORing the lower k bits of the bits of the first target secret key and the higher k bits of the bits of the second target secret key from the lower bits among the bits of the first target secret key. A multi-source authentication method for transmitting image data, characterized in that it is calculated by merging to the rear end of the front bits other than k bits. According to claim 1,
When a predetermined event occurs, the receiving or transmitting source further comprises the step of changing the session key to a new session key based on the secret key table,
If the change of the session key is determined, the value of the first identifier included in the secret key selection identifier is set to 1, multiple source authentication method for transmitting image data. The first device and the second device sharing a secret key table composed of n secret keys;
The first device generates a session key for calculating a message authentication code (MAC) and a secret key selection identifier for deriving the session key using at least one target secret key selected from the secret key table. To do;
The first device transmitting the secret key selection identifier to the second device; And
And the second device deriving the session key using the secret key selection identifier to calculate the MAC. The method of claim 10,
And the second device generating image data, a secret key selection identifier used for calculating the MAC, and transmitting data combining the MAC and transmitting the image data to and from the second device. Way. The method of claim 10,
The second device is a plurality of drones or a plurality of CCTV cameras, characterized in that the video data transmission and reception device authentication method. The method of claim 10,
The secret key selection identifier includes a first identifier indicating whether to maintain or change the session key, an identification number of a first target secret key to be used to generate the session key, and an identification number of a second target secret key to be used to generate the session key, And a number of bits to be used to generate the session key among bits of the first and second target secret keys,
The session key is a result of XORing the lower k bits of the bits of the first target secret key and the higher k bits of the bits of the second target secret key from the lower bits among the bits of the first target secret key. A method for authenticating a video data transmitting and receiving device, characterized in that it is calculated by merging with the trailing ends of the remaining front bits except k bits.

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