JP2004248167A - Communication control system, communication control method, program, and communication terminal device - Google Patents

Abstract

The present invention suppresses an increase in the amount of security information that needs to be managed in each NW node even when the number of nodes configuring the information communication network increases with the increase in the scale of the information communication network.
A communication control system for starting communication after establishing a security association (SA) for guaranteeing security between NW nodes A5a and B5b when communicating via an information communication network 1. Communication history information DB-A6a, -B6b for storing past communication history information in a storage device in association with a communication partner in A5a and B5b, and information common to the communication partner in the stored past communication history information. A configuration in which security information generating units 8a and 8b for generating key information corresponding to the communication partner and mutual authentication processing units 9a and 9b for establishing SA between the communication partner devices using the generated key information; I do.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a technique for establishing secure communication between communication terminal devices (NW nodes) connected via a network, with security being ensured. The present invention relates to a communication control technique suitable for efficiently establishing a security association (SA) in communication between different arbitrary NW nodes.
[0002]
[Prior art]
At present, with the spread of the Internet to general users, security (security) in a network system composed of an unspecified number of communication terminal devices (NW nodes) has become an issue. As described in 1 above, encryption technology to prevent eavesdropping on communication contents by a third party, authentication technology to prevent spoofing of others, tampering prevention technology using a signature to prevent forgery of messages, etc. Is being developed.
[0003]
In such an information communication system including an unspecified number of NW nodes, a security information centralized management system and a distributed management system are known as conventional techniques for guaranteeing security in communication between arbitrary NW nodes having different security policies. There are two methods.
[0004]
In the centralized management method, a third-party server (certificate authority) that guarantees security in common for two NW nodes having different security policies is installed, and each NW node that communicates with this server performs authentication. This is a client / server communication mode in which a procedure is executed and a security association (SA) is established between the NW nodes after each NW node is authenticated by a server.
[0005]
However, with this technology, there is a problem of scalability when applying to a large-scale network due to the concentration of processing load on the server, which is an adverse effect of centralized management, and collapse of security of the entire information communication system due to leakage of security information from the server There is a problem.
[0006]
On the other hand, the distributed management method is a P2P (Peer to Peer) that establishes a security association (SA) between arbitrary NW nodes having different security policies without installing a server as in the above-described centralized management method. Since it is a serverless communication type in which no server is installed, the above-mentioned problem of the centralized management method can be solved.
[0007]
However, in this distributed management method, it is necessary to perform mutual authentication between NW nodes having different security policies to establish an SA. To realize this, only two parties can be recognized by NW nodes having different security policies. In this case, the number (a) of security information (secret keys) required in this case increases in direct proportion to the square of the number of NW nodes (n) (“a = n × (n -1) / 2 ").
[0008]
Furthermore, if the security information is made variable for each communication in order to prevent a malicious user from impersonating the NW node, the number (b) of the variable security information (variable key) becomes the number (a) of the security information described above. ) Increases in direct proportion to the square of the information communication network. When the information communication network becomes large-scale and the number of nodes constituting the information communication network increases, the amount of security information managed by each NW node increases dramatically, and the security increases. A scalability problem arises in information management.
[0009]
[Non-patent document 1]
Edited by Takeshi Hattori and Masanobu Fujioka, “IDG Information and Communication Series Wireless Broadband Textbook”, First Edition, published by IDG Japan, June 2002, p. 437-457
[0010]
[Problems to be solved by the invention]
The problem to be solved is that, in the conventional technology, when the distributed management method for solving the problem of centralized management of security information is performed, the number of nodes configuring the information communication network increases with the increase in the size of the information communication network. In this case, the amount of security information that needs to be managed in each NW node is greatly increased.
[0011]
SUMMARY OF THE INVENTION An object of the present invention is to solve the problems of the related art, and to efficiently perform security assurance of communication between arbitrary NW nodes having different security policies on a network.
[0012]
[Means for Solving the Problems]
In order to achieve the above object, according to the present invention, security information necessary for establishing a security association (SA) in communication between arbitrary NW nodes having different security policies is replaced with past communication history information, for example, , The communication partner number, the communication history number, the communication start time, the communication data amount, the communication type, and the like.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 is a block diagram showing a configuration example of a communication control system according to the present invention, FIG. 2 is a sequence diagram showing a first processing operation example of the communication control system in FIG. 1, and FIG. FIG. 9 is a sequence diagram illustrating a second processing operation example of the communication control system.
[0015]
An NW node A 5a and an NW node B 5b that constitute the communication control system in FIG. 1 are computer devices including a CPU (Central Processing Unit), a main memory, a display device, an input device, an external storage device, and the like, and include an optical disk drive device and the like. After installing programs and data recorded on a storage medium such as a CD-ROM into the external storage device via the external storage device, the programs are read from the external storage device into the main memory and processed by the CPU to execute the functions of the respective processing units. I do.
[0016]
For example, the functions of the SA processing unit 7a including the security information generation unit 8a and the mutual authentication processing unit 9a and the communication history information DB-A6a (database) in the NW node A5a are realized by computer processing. The functions of the SA processing unit 7b including the security information generation unit 8b and the mutual authentication processing unit 9b, and the communication history information DB-A 6a (database) are realized by computer processing.
[0017]
In this example, a mobile communication network such as a mobile phone network is assumed as the information communication network 1. In the information communication network 1, there are three networks having different security policies, that is, a security policy network A2, a security policy network B3, and a security policy network C4. An NW node A5a is installed in the security policy network A2. Then, an NW node B5b is installed in the security policy network B3, and the NW node A5a and the NW node B5b are connected by a communication line 9 via a security policy network C4.
[0018]
The NW node A5a manages communication history information with other NW nodes in the information communication network 1 in a communication history information DB-A6a, and the NW node B5b manages communication history with other NW nodes in the information communication network 1. Information is managed by the communication history information DB-B6b.
[0019]
Each of the NW nodes A5a and B5b in the information communication network 1 is required to establish a security association (SA) that guarantees mutual validity before starting communication.
[0020]
In this example, the communication history information DB-A6a, DB-B6b and the SA processing units 7a, 7b are provided in each of the NW nodes A5a, B5b, and security information for each communication is generated using the communication history information common to each other. By performing mutual authentication between the NW nodes using the security information, the amount of security information managed by each of the NW nodes A5a and B5b is suppressed.
[0021]
That is, each time the NW nodes A5a and B5b of the information communication network 1 perform communication, the communication history information (address (name, number), communication history number, communication start time, communication data amount, communication type) of the communication partner node is performed. ) Are stored in the communication history information DB-A6a and DB-A6b of each of the NW nodes A5a and B5b.
[0022]
Thereafter, when communication is again performed between the same NW nodes A5a and B5b, the NW node A5a serving as a communication start request side establishes an SA between the NW nodes A5a and B5b by using an SA processing unit. 7a requests the communication history information DB-A 6a, searches the database for past communication history information with the NW node B 5b stored in the database, and obtains communication history information of the communication partner NW node B 5b.
[0023]
Then, in the SA processing unit 7a, the security information generation unit 8a selects a communication start time, a communication data amount, and a communication type from an arbitrary communication history number in the communication history information of the communication partner NW node B5b. Is generated by using an encryption key generation algorithm recognized by all NW nodes of the information communication network 1.
[0024]
Thereafter, the NW node A 5a uses the SA processing unit 7a to authenticate the authentication key generated from the communication history information by the security information generation unit 8a, the communication history number included in the communication history information used to generate the authentication key, and The address of the own NW node is transmitted to the NW node B5b of the communication partner.
[0025]
The NW node B 5b of the communication partner that has received the authentication key, the communication history number, and the address of the NW node A 5a that issues the communication start request requests the communication history information DB-B 6b by the SA processing unit 7b to start the communication. Using the address of the requesting NW node 5Aa and the communication history number as search key information, search its own database, obtain the communication history information designated by the NW node A5a, and generate security information for the SA processing unit 7b. The unit 8b selects a communication start time, a communication data amount, and a communication type included in the communication history information, and combines these pieces of information to generate an authentication key as security information.
[0026]
Then, the NW node B 5b transmits the address of its own NW node, the generated authentication key, and the communication history number to the NW node A 5a as the communication start request source by the SA processing unit 7b.
[0027]
The NW node A5a that has received the communication start request compares the authentication key generated by itself with the authentication key received from the communication partner NW node B5b in the mutual authentication processing unit 9a of the SA processing unit 7a. If the comparison results are the same, it recognizes that the communication partner NW node B5b is a valid NW node. If the comparison results are different, it is recognized that the communication partner node is an illegal NW node.
[0028]
When the NW node B 5b of the communication partner recognizes that it is a valid node, the NW node A 5a notifies the NW node B 5b of the communication partner of success information as an authentication result. Thereafter, an SA is established between the NW node A 5a and the NW node B 5b, and communication is started on the established SA.
[0029]
In this example, an authentication key, which is security information, is generated based on past communication history information between two NW nodes A5a and B5b that perform communication, so that management is required in each of the NW nodes A5a and B5b. The minimum value of the number of security information can be suppressed to the number (n) of NW nodes existing in the information communication network 1.
[0030]
For example, while the number (b) of authentication keys required by the conventional distributed management technology is “b = n × (n−1) / 2”, in the present example, the required security information It is possible to greatly reduce the number of authentication keys.
[0031]
Further, in order to prevent the communication history information of the communication history information DB of a specific NW node from being acquired by a malicious third party and impersonating this NW node, an authentication key which is security information for each communication is required. Must be a variable key.
[0032]
In this example, in order to prevent such spoofing, the NW node A5a that issues a communication start request selects a plurality of past communication history information related to a communication partner in the communication history information DB of the NW node A5a. And a cryptographic key generation algorithm recognized by all NW nodes of the information communication network to generate a variable key.
[0033]
Thus, in this example, even when the security information is changed to a variable key, the number of variable keys can be significantly reduced. That is, in the conventional distributed management technology, when the required number of variable keys (c) is calculated using the (b) authentication keys described above, “b × b = ｛n × (n−1) / 2｝ × {n × (n−1) / 2} ”, but according to this example, all NW nodes of the information communication network recognize a few pieces of history information from the past communication history information. An authentication key, which is security information, can be generated using the encryption key generation algorithm used.
[0034]
Further, in this example, the information transmitted and received between the NW nodes that perform communication is the authentication key generated by each node, the communication history number, and the name of the NW node that performs communication. Even when the third party has acquired the third party, the third party cannot acquire the past communication history information of the NW node required to generate the authentication key, so that it is possible to prevent spoofing to the NW node. It becomes possible.
[0035]
Next, the operation of the communication control system in FIG. 1 will be described with reference to FIG. FIG. 2 shows an SA establishment procedure required when starting communication between NW nodes having different security policies.
[0036]
When the NW node A5a installed in the security policy network A2 in FIG. 1 issues a communication start request to the NW node B5b installed in the security network B3 having a different security policy, the security policies are different from each other. It is necessary to start communication after establishing a security association (SA) for guaranteeing security between the NW node A5a and the NW node B5.
[0037]
The NW node A5a requests the communication history information DB-A6a held by the NW node A5a to acquire past communication history information with the communication partner NW node B5b (step S101).
[0038]
The communication history information DB-A 6a that has received the communication history information request from the NW node A 5a randomly selects a communication history number from the communication history information of the communication partner NW node B 5b, and communicates with the NW node B 5b based on the communication history number. The communication start time, the communication data amount, and the communication type, which are the communication history information, are acquired (step 102). As the communication history information of the NW node B 5b, the address of the NW node B 5b, the communication history number, the communication start time, the communication data amount, The communication type is transmitted to the NW node A5a (step 103).
[0039]
The NW node A5a generates an authentication key for the information using an encryption key generation algorithm recognized by all NW nodes of the information communication network, and temporarily stores the authentication key for the NW node B5b (step S104). ), Sends the generated and stored authentication key, communication history number, and node address of the own NW node A5a to the NW node B5b (step S105).
[0040]
The NW node B 5b that has received the authentication key, the communication history number, and the address of the node of the NW node A 5a generated from the NW node A 5a sends the communication history information DB-B 6b held by itself to the NW node A 5a of the communication partner. Of the past communication history information is requested (step S106).
[0041]
The communication history information DB-A8 that has received the communication history information request from the NW node B5b selects the communication history number specified in the communication history information of the communication partner NW node A5a, and determines the NW node A5a from this communication history number. The communication start time, the communication data amount, and the communication type, which are the communication history information of the NW node A5a, are acquired (step S107), and the address, the communication history number, the communication start time, the communication data amount, The communication type is transmitted to the NW node B 5b (step S108).
[0042]
The NW node B5b generates an authentication key using the encryption key generation algorithm recognized by all NW nodes of the information communication network (step S109), and generates the authentication key, the communication history number, and the NW node. The address of the node B5b is transmitted to the NW node A5a (step S110).
[0043]
The NW node A5a that has received the authentication key, communication history number, and node address of the NW node B5b generated from the NW node B5b compares the authentication key for the NW node B5b temporarily stored with the received authentication key. When the comparison result is the same, the communication partner NW node B5b is recognized as a valid NW node, and when the comparison result is different, the communication partner NW node B5b is recognized as an illegal NW node ( Step S111).
[0044]
When recognizing that the NW node B 5b of the communication partner is a valid node, the NW node A 5a notifies the NW node B 5b of success information as an authentication result (step S112).
[0045]
After that, a security association (SA) is established between the NW node A 5a and the NW node B 5b (step S113), and communication is performed on the established SA (step S114).
[0046]
Next, another operation of the communication control system in FIG. 1 will be described with reference to FIG. FIG. 3 shows an SA establishment procedure when a variable key is used for each communication when starting communication between NW nodes having different security policies.
[0047]
When the NW node A5a installed in the security policy network A2 in FIG. 1 issues a communication start request to the NW node B5b installed in the security network B3 having a different security policy, the security policies are different from each other. It is necessary to start communication after establishing a security association (SA) for guaranteeing security between the NW node A5a and the NW node B5.
[0048]
The NW node A5a requests the communication history information DB-A6a held by the NW node A5a to acquire past communication history information with the communication partner NW node B5b (step S201).
[0049]
Upon receiving the communication history information request from the NW node A5a, the communication history information DB-A6a randomly selects a plurality of communication history numbers from the communication history information of the NW node B5b of the communication partner, and selects the NW node B5b from the plurality of communication history numbers. The communication start time, the communication data amount, and the communication type, which are the communication history information with the NW node B5b, are obtained as a single set for a plurality of communication history numbers (step S202). The address, communication history number, communication start time, communication data amount, and communication type are transmitted to the NW node A5a (step S203).
[0050]
The NW node A5a generates the authentication key using the encryption key generation algorithm recognized by all NW nodes of the information communication network, and temporarily stores the authentication key for the NW node B5b ( In step S204, the generated authentication key, the plurality of communication history numbers, and the address of the node of the NW node A5a are transmitted to the NW node B5b (step S205).
[0051]
The NW node B 5b, which has received the authentication key generated from the NW node A5a, the plurality of communication history numbers, and the address of the node of the NW node A5a, transmits the NW node of the communication partner to the communication history information DB-B6b held by itself. A request for acquiring past communication history information with A5a is made (step S206).
[0052]
The communication history information DB-B 6b that has received the communication history information request from the NW node B 5b selects a plurality of communication history numbers specified in the communication history information of the NW node A 5a of the communication partner, and selects the NW from the plurality of communication history numbers. The communication start time, the communication data amount, and the communication type, which are the communication history information with the node A5a, are acquired (step S207), and the address of the NW node A5a, the plurality of communication history numbers, and the plurality of communication are obtained as the communication history information of the NW node A5a. The communication start time, the communication data amount, and the communication type corresponding to the history number are transmitted to the NW node B 5b (step S208).
[0053]
The NW node B 5b generates an authentication key using the encryption key generation algorithm recognized by all NW nodes of the information communication network (step S209), and generates the authentication key, a plurality of communication history numbers, The node address of the NW node B5b is transmitted to the NW node A5a (step S210).
[0054]
The NW node A5a, which has received the authentication key generated from the NW node B5b, the plurality of communication history numbers, and the node address of the NW node B5b, stores the authentication key for the NW node B5b temporarily stored therein and the received authentication key. If the comparison result is the same, the NW node B 5b of the communication partner recognizes that it is a legitimate NW node. If the comparison result is different, it is determined that the NW node B 5b of the communication partner is an illegal NW node. Recognize (step S211).
[0055]
When recognizing that the NW node B 5b of the communication partner is a legitimate node, the NW node A 5a notifies the NW node B 5b of success information as an authentication result (step S212).
[0056]
After that, a security association (SA) is established between the NW node A 5a and the NW node B 5b (step S213), and communication is performed on the established SA (step S214).
[0057]
As described above with reference to FIGS. 1 to 3, in this example, a system that controls connection between communication terminal devices that perform communication via a network, particularly communication between communication terminal devices via a network, In performing the communication, in a communication control system that starts communication after establishing a security association for guaranteeing security between the devices, the past communication history information is communicated to each of the communication terminal devices (NEW nodes 5a and 5b). Communication history information management DB-A6a and DB-B6b stored in the storage device in association with the other party, and past communication history information stored in the communication history information management DB-A6a and DB-B6b. Security information generation units 8a and 8b that generate key information corresponding to the communication partner using the security information generation units 8a and 8b. And a mutual authentication processing section 9a, 9b for establishing a security association between the communication terminal apparatuses of the communication partner using the key information generated in the above, and performing communication control with security assurance between the apparatuses. I have.
[0058]
Thus, in a communication between arbitrary NW nodes having different security policies in an information communication network composed of an unspecified number of NW nodes, when establishing a security association (SA) between nodes before starting communication. Can be generated from past communication history information, and the amount of security information managed by each NW node can be suppressed. Even when the number of NW nodes constituting the information communication network increases, the amount of security information managed by each NW node can be suppressed.
[0059]
As described above, in this example, the communication history information is used for the recognition processing. However, in the recognition processing, information that can be recognized only by two parties is generally used for the recognition information. Since the information can be known only by the two persons who have performed the authentication, the information can be used as an authentication key.
[0060]
Further, such communication history information is collected and stored in each terminal on a general network or a communication carrier, and does not generate a new cost for the present invention.
[0061]
It should be noted that the present invention is not limited to the example described with reference to FIGS. 1 to 3 and can be variously modified without departing from the gist thereof. For example, in the present example, a mobile communication network such as a mobile phone network is assumed as the information communication network 1, but the present invention is also applicable to other networks such as the Internet.
[0062]
If there is a rule that discards certain communication information after a certain period of time, the communication history information does not need to be number-managed and information management becomes easy.
[0063]
Also, the computer configuration of the NW node (communication terminal device) in this example may be a computer configuration without a keyboard or a drive for an optical disk. Also, in this example, the use of an optical disk as a recording medium has been described, but an FD (Flexible Disk) or the like may be used as the recording medium. As for the installation of the program, the program may be downloaded and installed via a network via a communication device.
[0064]
【The invention's effect】
According to the present invention, even when the number of nodes configuring the information communication network increases with the increase in the size of the information communication network, the amount of security information that needs to be managed in each NW node does not increase significantly. It is possible to efficiently guarantee the security of communication between arbitrary NW nodes having different security policies on the network.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration example of a communication control system according to the present invention.
FIG. 2 is a sequence diagram showing a first processing operation example of the communication control system in FIG. 1;
FIG. 3 is a sequence diagram showing a second processing operation example of the communication control system in FIG. 1;
[Explanation of symbols]
1: information communication network, 2: security policy network A, 3: security policy network B, 4: security policy network C, 5a: NW node A, 5b: NW node B, 6a: communication history information DB-A, 6b: Communication history information DB-B, 7a, 7b: SA processing unit, 8a, 8b: security information generation unit, 9a, 9b: mutual authentication processing unit, 10: communication line.

Claims (13)

A system for controlling connection between communication terminal devices that communicate via a network,
For each of the above communication terminal devices,
Communication history information management means for storing past communication history information in a storage device in association with a communication partner,
Key generation means for generating key information corresponding to the communication partner using information common to the communication partner in the past communication history information stored in the communication history information management means,
Means for performing communication control with security assurance between the communication terminals of the communication partner using the key information generated by the key generation means. A communication control system for starting communication after establishing a security association for guaranteeing security between devices when performing communication between communication terminal devices over a network,
For each of the above communication terminal devices,
Communication history information management means for storing past communication history information in a storage device in association with a communication partner,
Key generation means for generating key information corresponding to the communication partner using information common to the communication partner in the past communication history information stored in the communication history information management means,
Means for establishing a security association between the communication terminal devices of the communication partner using the key information generated by the key generation means. The communication control system according to claim 1 or 2, wherein:
The communication history information management means includes:
When the communication with the communication terminal device of the communication partner is completed, the communication history information includes identification information of the communication partner, a communication history number, a communication start time, a communication data amount, and a communication type. A communication control system comprising: The communication control system according to claim 1 or 2, wherein:
The communication history information management means includes:
Means for storing, in the storage device, identification information of the communication partner, a communication history number, a communication start time, a communication data amount, and a communication type as the communication history information at the end of communication with the communication terminal device of the communication partner. ,
The key generation means randomly selects a plurality of communication history numbers for each communication partner, a communication start time corresponding to the communication history number, a communication data amount, and a communication type, and sets a predetermined encryption key generation algorithm. A communication control system comprising means for generating the key information as a variable key using the key information. A communication control method in a system that performs secure connection control between communication terminal devices that perform communication via a network,
In each of the above communication terminal devices,
A first procedure of storing past communication history information in a storage device in association with a communication partner;
A second procedure of generating key information corresponding to the communication partner by using information common to the communication partner in the past communication history information stored in the first procedure;
Using the key information generated in the second procedure, and performing a third procedure of performing communication control with security assurance between the communication terminals of the communication partner. A communication control method in a system for starting communication after establishing a security association for guaranteeing security between devices when performing communication between communication terminal devices via a network,
In each of the above communication terminal devices,
A first procedure of storing past communication history information in a storage device in association with a communication partner;
A second procedure of generating key information corresponding to the communication partner by using information common to the communication partner in the past communication history information stored in the first procedure;
Using the key information generated in the second procedure to execute a third procedure for establishing a security association between the communication terminals of the communication partner. A communication control method according to claim 5 or claim 6, wherein
In the first procedure, at the end of communication with the communication terminal device of the communication partner, the communication history information includes the identification information of the communication partner, the communication history number, the communication start time, the communication data amount, and the communication type. A communication control method characterized by storing in a storage device. A communication control method according to claim 5 or claim 6, wherein
In the first procedure, when the communication with the communication terminal device of the communication partner ends, the identification information of the communication partner, the communication history number, the communication start time, the communication data amount, and the communication type are stored as the communication history information in the storage device. To remember
In the second procedure, a plurality of communication history numbers, a communication start time, a communication data amount, and a communication type corresponding to the communication history numbers are randomly selected for each communication partner, and a predetermined encryption key generation algorithm is provided. A communication control method, wherein the key information is generated as a variable key using A program for causing a computer to execute each procedure in the communication control method according to claim 5. A communication terminal device that performs communication via a network, and a communication history information management unit that stores past communication history information in a storage device in association with a communication partner,
Key generation means for generating key information corresponding to the communication partner using information common to the communication partner in the past communication history information stored in the communication history information management means,
Means for performing communication control with security assurance between the communication terminal apparatuses of the communication partner using the key information generated by the key generation means. When communicating with a communication terminal device of the other party through a network, after establishing a security association for guaranteeing security between the devices, a communication terminal device that starts communication,
Communication history information management means for storing past communication history information in a storage device in association with a communication partner,
Key generation means for generating key information corresponding to the communication partner using information common to the communication partner in the past communication history information stored in the communication history information management means,
Means for establishing a security association with the communication terminal device of the communication partner using the key information generated by the key generation means. The communication terminal device according to claim 11, wherein
In the communication history information management means,
At the end of communication with the communication terminal device of the communication partner, the identification information of the communication partner, the communication history number, the communication start time, the communication data amount, and the communication type are all stored in the storage device as the communication history information. Characteristic communication terminal device. The communication terminal device according to claim 11, wherein
In the communication history information management means, at the end of communication with the communication terminal device of the communication partner, the identification information of the communication partner, the communication history number, the communication start time, the communication data amount, and the communication type are stored as the communication history information. Memorize in the device,
In the key generation means, a plurality of communication history numbers for each communication partner, a communication start time corresponding to the communication history number, a communication data amount, and a communication type are randomly selected, and a predetermined encryption key generation algorithm is set. A communication terminal device for generating the key information as a variable key using the key information.

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