JP2005260448A - One-to-multiple secure communication system, communication management device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize one-to-multiple secure communication capable of data transmission without recognizing group members, and capable of replay defence employing a sequence number. <P>SOLUTION: An agent server 2 (communication management device) receives a one-to-multiple transmission request from a member terminal becoming a source, acquires secure information of a member group from secure information established with a member terminal 1, creates secure data using the secure information of the member group, and transmits it to a member terminal belonging to the member group. The destination member terminal 1 receives secure data being transmitted from the communication management device using the secure information of the member group. Transmitter of one-to-multiple communication becomes an agent server 2 without fail via the agent server 2. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a one-to-many secure communication system, a communication management apparatus, and a method in which a plurality of member terminals connected to a network are connected via a communication management apparatus that relays access.

  In one-to-one secure communication, confirmation using a normal sequence number is performed in order to prevent unauthorized duplication and transmission of packets (hereinafter referred to as replay). For example, in the case of IPsec (Security Architecture for Internet Protocol), the sender sends the transmission data with a transmission sequence number, and the receiver sends the sequence number included in the received data and the already received data. Is compared with the sequence number included in. By this comparison operation, the receiver confirms whether or not the data has already been received.

In the case of SSL (Secure Socket Layer), the sender generates an authentication code from the transmission data and the transmission sequence number. The sender transmits the transmission data and the authentication code, and the receiver generates the authentication code from the reception data and the reception sequence number managed by the reception number. Then, by comparing that the generated authentication code and the received authentication code are the same, the receiver confirms that the data transmitted from the sender is received in order (for example, (Refer nonpatent literature 1.).
IPsec: RFC2401 Security Architecture for the Internet Protocol, S. Kent, BBN Corp, R.C. Atkinson, @ Home Network, November 1998

  On the other hand, in one-to-many secure communication, there are a plurality of senders and receivers. Thus, in a situation where anyone can be a sender, the management method of sequence numbers becomes a problem. Here, it is assumed that the sequence number is managed for each sender or is commonly managed for a plurality of senders.

In the former case, the receiver needs to manage a plurality of sequence numbers. Normally, the sequence number is managed as secure communication information, but secure communication information excluding the sequence number is managed in common for a plurality of senders and receivers belonging to the member group. For this reason, the sender or the receiver needs a function of managing a plurality of pieces of secure communication information for each member group.
In the latter case, if a plurality of senders transmit data at the same time, the same sequence number may be given to different transmission data. In that case, the data that has arrived first is received correctly, but the subsequent data is discarded. Thus, in an environment where a plurality of senders exist, there is a problem that replay protection using a sequence number does not function normally.

  The present invention has been made in view of the above circumstances, and belongs to a member group that can protect against relay using a sequence number by performing one-to-many secure communication via a communication management device that relays access. It is an object of the present invention to provide a one-to-many secure communication system, a communication management apparatus, and a method that enable data transmission without being conscious of the member who performs the operation.

  In order to solve the above-described problems, the present invention provides a one-to-many secure communication system in which a plurality of member terminals connected to a network are connected via a communication management device that relays access, the communication management device A transmission request receiving unit that receives a one-to-many transmission request from the member terminal that is a transmission source, a secure information acquisition unit that acquires secure information of a member group from secure information established between the member terminals, A secure data generating / transmitting unit configured to generate secure data using the acquired secure information of the member group and transmit the data to a member terminal belonging to the member group serving as a transmission destination; and the member serving as the transmission destination The terminal receives the secured data transmitted from the communication management device using the secure information of the member group And wherein the Rukoto.

  In order to solve the above problems, the present invention is the communication management apparatus in a one-to-many secure communication system in which a plurality of member terminals connected to a network are connected via a communication management apparatus that relays access. A transmission request receiving unit that receives a one-to-many transmission request from the member terminal that is a transmission source, a secure information acquisition unit that acquires secure information of a member group from secure information established with the member terminal, A secure data generating / transmitting unit configured to generate secure data using the acquired secure information of the member group and transmit the data to a member terminal belonging to the member group as a transmission destination;

  In order to solve the above problems, the present invention is a secure communication method used in a one-to-many secure communication system in which a plurality of member terminals connected to a network are connected via a communication management device that relays access. Receiving a one-to-many transmission request from the member terminal serving as a transmission source, obtaining secure information of a member group from secure information established with the member terminal, and Generating secure data using secure information and transmitting the data to a member terminal belonging to the member group as a transmission destination; and securing transmitted from the communication management device using the secure information of the member group Receiving received data.

According to the present invention, a communication management apparatus receives a one-to-many transmission request from a member terminal serving as a transmission source, acquires secure information of a member group from secure information established with the member terminal, and By generating secure data using secure information and transmitting it to the member terminals belonging to the member group that is the transmission destination, the member terminal that is the transmission destination is transmitted from the communication management device using the secure information of the member group. Secured data can be received.
Thus, the sender of the one-to-many communication always becomes the communication management device by way of the communication management device, and the sender belongs to the member group because the communication management device acts as a member group management agent. It is possible to transmit data without being aware of the member who performs, and to realize one-to-many secure communication capable of replay protection using a sequence number.

  Further, one secure communication is established from the member terminal serving as the transmission source to the communication management device, one sequence number is managed for the secure communication, and the communication management device includes the member group serving as the transmission destination. By establishing secure communication for the member terminals belonging to and managing the sequence number for each secure communication, it is possible to avoid situations where the member terminal that is the sender manages multiple sequence numbers or updates the sequence number And replay protection can be realized while reducing the burden on the member terminals.

FIG. 1 is a diagram showing an example of a system configuration of a one-to-many secure communication system according to the present invention.
As shown in FIG. 1, the one-to-many secure communication system includes a member terminal 1 connected via a network and a proxy server 2 as a communication management apparatus in the present invention. Each member terminal 1 is a transmission source or a transmission destination, and its access is relayed by the proxy server 2, whereby one-to-many secure communication is realized. Here, an example using IPsec is shown as an example of secure communication.

  By the way, IPsec is a protocol for performing encryption, message authentication, and partner authentication, and is most popular as a method for realizing VPN (Virtual Private Network). IPsec is roughly divided into three protocols: IKE (Internet Key Exchange), AH (Authentication Header), and ESP (Encapsulating Security Payload). By the way, IKE prescribes the procedure for generating / regenerating a secure communication path (SA: Security Association) and SA management method by performing partner authentication, and AH is the SA generated by IKE (can also be set manually) ) Is used to define the data transmission procedure that ensures the authentication and integrity of the sender, and the ESP uses the SA generated by IKE to secure the authentication, integrity and confidentiality of the sender. It defines the transmission / reception procedure.

  FIG. 2 is a block diagram showing an expanded function of the internal configuration of the proxy server 2. As shown in FIG. 2, the proxy server 2 includes a communication interface unit 21, a transmission request receiving unit 22, an SA information acquisition unit 23, a secure data generation unit 24, a data transmission unit 25, and a sequence number management unit. 26, an SA information management table 27, and a group information management table 28, which are roughly divided functionally.

The communication interface unit 21 has a function of establishing secure communication with the member terminal 1 by IPsec. The transmission request receiving unit 22 has a function of receiving a one-to-many transmission request from the member terminal 1 serving as a transmission source and supplying it to the SA information acquiring unit 23. The SA information acquisition unit 23 acquires member group information from secure information established with the member terminal 1 via the communication interface unit 21, and the member terminal 1 serving as the transmission source is the transmission source from the member group information. It has a function of confirming with the group management table 28 whether it belongs to a member group. Further, it has a function of acquiring SA identification information from the SA information management table 27 and supplying it to the secure data generation unit 24.
The secure data generation unit 24 has a function of generating secure data using the SA identification information of the member group acquired by the SA information acquisition unit 23, and the data transmission unit 25 is secured by the secure data generation unit 24. It has a function of transmitting the digitized data to the member terminal 1 belonging to the member group as the transmission destination. In the present invention, the secure data generation unit 24 and the data transmission unit 25 are collectively referred to as a secure data generation / transmission unit.

The sequence number management unit 26 manages the sequence number for each group member for each secure communication established with the member terminal 1 serving as a transmission source, and secure communication with the member terminal 1 serving as a transmission destination. And has a function of managing a sequence number for each secure communication.
The SA information management table 27 stores group identifiers and SA identification information. For each group identifier, “security parameter index value” and “type of security protocol (IPsec protocol) such as AH or ESP”. , SA identification information including “end point IP address” is associated. FIG. 3A shows an example of the data structure. Further, the “security parameter index value” needs to be issued a unique value for each SA.

On the other hand, the group information management table 28 stores information on the group to which each member belongs, and as shown in FIG. 3B, is composed of a pair of member identifier and group identifier to which the member belongs. .
In addition, it is necessary to register group information and member information in advance to the proxy server 2 before registering members to the group. The registration method can be offline based on a contract or application, or online using a network. It doesn't matter. However, since security is important, care must be taken in registration.

  Note that, in realizing the one-to-many secure communication system of the present invention, the member acquires information (host name / IP address, etc.) of the proxy server 2, and each member is included in the proxy server 2. It is assumed that the information of the group to which it belongs is stored. Further, it is assumed that the proxy server 2 stores information (SA identification information and the like) generated for establishing secure communication between groups. Further, the member establishes one-to-one IPsec communication with the proxy server 2, and acquires information necessary for establishing secure communication between the groups from the proxy server 2 through this secure communication. Shall be kept. Since the SA identification information is used for SA search, information such as a security parameter index value, a type of security protocol (IPsec protocol) such as AH or ESP, and an end point IP address is required.

FIG. 4 is a diagram for explaining the operation of the one-to-many secure communication system according to the present invention, and shows an operation sequence between the member terminal 1 and the proxy server 2.
The detailed operation of the one-to-many secure communication system will be described below with a focus on the operation of the proxy server 2 shown in FIG. 2 with reference to the operation sequence diagram shown in FIG.

  First, the member A who wants to transmit data to all members of the group uses the one-to-one IPsec communication established with the proxy server 2 to transmit the transmission data to the group members, the transmission destination group, and the like. The transmission request information including it is generated (S0) and transmitted to the proxy server 2 (S1).

  In the proxy server 2, the transmission request receiving unit 22 receives the transmission request information from the member A serving as the transmission source. Next, the SA information acquisition unit 23 acquires the member group information from the transmission request information, and the member A Is confirmed by the group information management table 28 and SA identification information is acquired from the SA information management table 27 (S2). The secure data generation unit 24 generates secure data using the SA identification information of the acquired group (S3), and the data transmission unit 25 performs one-to-many (multicast or broadcast) transmission destination. Data is transmitted to the group members (members A, B, C, and D) that become (S4).

  The group member receives data transmitted from the proxy server 2 using information necessary for establishing secure communication between the groups (S5). Here, even if a member who does not belong to the group receives the data, it does not have information necessary for establishing secure communication between the groups, so that the data cannot be decoded.

Here, FIG. 5 shows a conceptual diagram of the operation of the one-to-many secure communication system of the present invention, and a supplementary explanation will be given for the management of sequence numbers.
As shown in the figure, the communication mode (one-to-one or one-to-many) and the sequence number management method differ between communication from the transmission side to the proxy server 2 and communication from the proxy server 2 to the reception side.
First, one-to-one secure communication is established between the transmission side and the proxy server 2, and basically data is transmitted from the transmission side to the proxy server 2. For this secure communication, one sequence number is updated (incremented) on the transmission side. For this reason, the problem regarding replay does not occur.

  On the other hand, one-to-many secure communication is established between the proxy server 2 and the receiving side, and data is always transmitted from the proxy server 2 to the receiving side. Further, for this secure communication, the sequence number management unit 26 of the proxy server 2 updates the sequence number, so that special management of the sequence number by the transmission side and the reception side as in the conventional case is not required. Replay protection can be realized.

  As described above, according to the present invention, the proxy server 2 as a communication management apparatus receives a one-to-many transmission request from the member terminal 1 serving as a transmission source, and the member group is obtained from the secure information established with the member terminal 1. The member terminal 1 serving as the transmission destination can obtain the secure information using the secure information of the member group, generate the secure data using the member group secure information, and transmit the data to the member terminals belonging to the member group serving as the transmission destination. By transmitting to the member terminal 1 belonging to the group, the member terminal 1 as the transmission destination can receive the secured data transmitted from the proxy server using the secure information of the member group. .

In the present invention, for example, when there is a reliable server A and a certain member B is in a trust relationship with the server A, another member C in a trust relationship with the server A can trust the member B. Is assumed. Based on the above assumptions, when the proxy server 2 is a reliable server, and the sender performs mutual authentication with the proxy server 2 and is in a trust relationship, the receiver is a sender in a trust relationship with the proxy server 2 Can be said to be reliable. At this time, the sender can transmit data without being conscious of the member terminals 1 belonging to the member group, and all the member terminals 1 can communicate with each other via the proxy server 2. Data can be transmitted to all member terminals 1 of the member group to which it belongs.
According to the present invention, the member terminal 1 can participate in a plurality of groups.

It is a figure which shows an example of the system configuration | structure of this invention embodiment. It is the block diagram which expanded the function and showed the internal structure of embodiment of this invention. It is the figure which showed an example of the data structure of the table used by this invention embodiment. It is an operation | movement sequence diagram which shows operation | movement of this invention embodiment. It is a figure which shows the operation | movement concept of embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Member terminal, 2 ... Proxy server (communication management apparatus), 21 ... Communication interface part, 22 ... Transmission request receiving part, 23 ... SA information acquisition part, 24 ... Secure data generation part, 25 ... Data transmission part, 26 ... Sequence number management unit, 27 ... SA information management table (TBL), 28 ... Group information management table (TBL),

Claims (3)

A one-to-many secure communication system in which a plurality of member terminals connected to a network are connected via a communication management device that relays access,
The communication management device
A transmission request receiving unit that receives a one-to-many transmission request from the member terminal serving as a transmission source;
A secure information acquisition unit for acquiring member groove secure information from secure information established with the member terminal;
A secure data generation / transmission unit that generates secure data using the acquired secure information of the member group and transmits the data to a member terminal belonging to the member group that is a transmission destination,
The one-to-many secure communication system, wherein the member terminal as the transmission destination receives the secured data transmitted from the communication management device using the secure information of the member group. A plurality of member terminals connected to a network are connected via a communication management device that relays access, the communication management device in a one-to-many secure communication system,
A transmission request receiving unit that receives a one-to-many transmission request from the member terminal serving as a transmission source;
A secure information acquisition unit for acquiring member groove secure information from secure information established with the member terminal;
A secure data generation / transmission unit that generates secure data using the acquired secure information of the member group, and transmits the data to a member terminal belonging to the member group as a transmission destination;
A communication management device comprising: A secure communication method used in a one-to-many secure communication system in which a plurality of member terminals connected to a network are connected via a communication management device that relays access,
Receiving a one-to-many transmission request from the member terminal serving as a transmission source;
Obtaining secure information of a member groove from secure information established with the member terminal;
Generating secure data using the acquired secure information of the member group, and transmitting the data to a member terminal belonging to the member group as a transmission destination;
Receiving secured data transmitted from the communication management device using secure information of the member group;
A secure communication method comprising:

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