WO2015129196A1 - Confidential communication system, and method for delivering secret key in confidential communication system - Google Patents

Confidential communication system, and method for delivering secret key in confidential communication system Download PDF

Info

Publication number
WO2015129196A1
WO2015129196A1 PCT/JP2015/000701 JP2015000701W WO2015129196A1 WO 2015129196 A1 WO2015129196 A1 WO 2015129196A1 JP 2015000701 W JP2015000701 W JP 2015000701W WO 2015129196 A1 WO2015129196 A1 WO 2015129196A1
Authority
WO
WIPO (PCT)
Prior art keywords
processing unit
secret key
information
information processing
shared secret
Prior art date
Application number
PCT/JP2015/000701
Other languages
French (fr)
Japanese (ja)
Inventor
操 福田
Original Assignee
日本電気株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 日本電気株式会社 filed Critical 日本電気株式会社
Publication of WO2015129196A1 publication Critical patent/WO2015129196A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/08—Key distribution or management, e.g. generation, sharing or updating, of cryptographic keys or passwords
    • H04L9/0816—Key establishment, i.e. cryptographic processes or cryptographic protocols whereby a shared secret becomes available to two or more parties, for subsequent use
    • H04L9/0852—Quantum cryptography
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L9/00—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols
    • H04L9/32—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials
    • H04L9/3236—Cryptographic mechanisms or cryptographic arrangements for secret or secure communications; Network security protocols including means for verifying the identity or authority of a user of the system or for message authentication, e.g. authorization, entity authentication, data integrity or data verification, non-repudiation, key authentication or verification of credentials using cryptographic hash functions

Definitions

  • the present invention relates to a secret communication system in which secret communication is performed and a secret key distribution method in the secret communication system.
  • an information processing system including a server and a plurality of switches respectively connected to the server.
  • a client computer is connected to each switch.
  • the shared secret key is used to encrypt the information.
  • Patent Document 1 describes that one key sharing apparatus and the other key sharing apparatus connected to a communication network share a one-time pad key.
  • Patent Document 2 describes the use of quantum cryptography as a secret key.
  • the information transmitting side and the receiving side share a secret key.
  • each client computer that transmits and receives information more specifically, each switch to which each client computer is connected must share a secret key.
  • a one-time pad key described in Patent Document 1 or a secret key using quantum cryptography described in Patent Document 2 is physically stored in a server and each switch. And are manually entered into each device.
  • the present invention provides a secret communication system and a secret key distribution method in a secret communication system that can make communication between information transmission apparatuses such as switches connected to a communication network highly confidential with less effort and low cost.
  • the purpose is to do.
  • a confidential communication system includes a plurality of information transmission devices connected to a communication network, and information processing units each connected to the information transmission devices via a communication line, the information processing unit and the information transmission device
  • Each of the communication line connection shared secret keys is generated, and the information processing unit compares each of the communication line connection shared secret keys with each other, and the entire shared secret key between the information processing unit and each information transmission device. Is generated based on the comparison result, and the comparison result is transmitted to each information transmission device, and each of the information transmission devices is configured to process the information processing unit based on the transmitted comparison result and the communication line connection shared secret key. And an overall shared secret key for each information transmission apparatus.
  • each of the plurality of information transmission devices connected to the communication network and each of the information processing units connected to each information transmission device by a communication line communicate with each other.
  • an overall shared secret key generation unit side step in which the information processing unit generates the entire overall shared secret key of the information processing unit and each information transmission apparatus based on the comparison result based on the result of the comparison step;
  • the information processing unit transmits the comparison result in the comparison step to each information transmission device.
  • the information transmission device respectively generate an overall shared secret key for the information processing unit and each information transmission device based on the transmitted comparison result and the communication line connection shared secret key.
  • a secret key generation device side step in which the information processing unit generates the entire overall shared secret key of the information processing unit and each information transmission apparatus based on the transmitted comparison result and the communication line connection shared secret
  • communication between information transmission apparatuses such as switches connected to a communication network can be made highly confidential with less effort and low cost.
  • FIG. 1 is a block diagram showing a configuration example of a confidential communication system according to the first embodiment of this invention.
  • the confidential communication system according to the first embodiment of the present invention includes an information processing unit 100 and switches (information transmission apparatuses) 500a to 500d.
  • the information processing unit 100 is connected to the switches 500a to 500d via the communication line 200, respectively.
  • the switches 500a to 500d are connected to a LAN or WAN (hereinafter referred to as LAN / WAN (communication network)) 300.
  • LAN / WAN communication network
  • client computers 400a to 400d for transmitting and receiving packetized confidential information to and from the information processing unit 100 are connected to the switches 500a to 500d, respectively.
  • the switches 500a to 500d relay the packets so that the packets are transmitted and received through the appropriate communication path between the information processing unit 100 and the client computers 400a to 400d.
  • the switches 500a to 500d are preferably PF (Programmable Flow) switches corresponding to OpenFlow (registered trademark), but may be other switches as long as they have the functions described below.
  • the communication circuit 200 is realized by, for example, an optical communication line such as an optical fiber, but may be realized by another communication medium or a wireless communication line as long as photons can be transmitted. 1 illustrates four switches 500a to 500d, but the number of switches 500 may be less than four, or may be five or more.
  • a plurality of client computers may be connected to each of the switches 500a to 500d, or other devices may be connected.
  • the information processing unit 100 includes an administrator unit 101, a DaAS (Desktop as a Service) server unit 102, and a single photon generation unit 103.
  • the single photon generation unit 103 generates photons linearly polarized at a predetermined angle in accordance with an instruction from the DaaS server unit 102.
  • the DaS server unit 102 transmits and receives information to and from the switches 500a to 500d and the client computers 400a to 400d in accordance with instructions from the administrator unit 101. Further, the DaaS server unit 102 transmits the photons generated by the single photon generation unit 103 to the switches 500a to 500d in accordance with instructions from the administrator unit 101.
  • the administrator unit 101 and the DaaS server unit 102 may be realized by separate computers, or may be realized by a single computer. Further, instead of the information processing unit 100 including the single photon generation unit 103, the DaaS server unit 102 may have a function of generating photons linearly polarized at a predetermined angle.
  • FIG. 2 is a sequence diagram showing an operation of generating a shared secret key shared by the information processing unit 100 and the switches 500a to 500d.
  • the quantum cipher is delivered to each of the switches 500a to 500d based on the BB84 method.
  • the DaS server unit 102 and each of the switches 500a to 500d respectively generate a random number sequence having the same number of digits in which bit values of “0” or “1” are randomly arranged (step S101, S102).
  • the DaaS server unit 102 may generate a random number sequence in accordance with an instruction from the administrator unit 101, or may receive provision of a random number sequence generated by a random number generator (not shown).
  • the DaAS server unit 102 transmits photons according to the random number sequence generated in the process of step S101 to the switches 500a to 500d via the communication line 200 according to the instruction of the administrator unit 101 (step S103). Specifically, when transmitting the photon corresponding to the digit of the bit value “1” in the random number sequence, the DaaS server unit 102 is 135 ° with respect to the linearly polarized light in the vertical direction (that is, 0 °) or the vertical direction. One of the linearly polarized light is randomly selected. Then, the DaaS server unit 102 transmits the selected linearly polarized photon in the process of step S103.
  • the DaaS server unit 102 when transmitting the photon corresponding to the digit of the bit value “0” in the random number sequence, the DaaS server unit 102 linearly polarized light in the horizontal direction (that is, 90 °) or linearly polarized light of 45 ° with respect to the vertical direction. One of the above is selected at random. Then, the DaaS server unit 102 transmits the selected linearly polarized photon in the process of step S103.
  • Each switch 500a to 500d receives the photon transmitted by the DaaS server unit 102 in the process of step S103, and observes the polarization state of the received photon (step S104). Specifically, for example, according to the random number sequence generated in step S102, a filter (not shown) included in a photon receiver (not shown) built in switches 500a to 500d is processed in step S103. The photon transmitted in is made incident.
  • the filter is, for example, a calcite crystal.
  • each of the switches 500a to 500d changes the direction of the filter according to the random number sequence generated in the process of step S102.
  • Differentiating the direction of the filter according to the random number sequence means that, for example, when receiving a photon corresponding to a digit whose bit value is “1” in the random number sequence, the linearly polarized light in the vertical direction or the linearly polarized light in the horizontal direction
  • the direction of the filter is set so that photons are output.
  • a linearly polarized photon of 45 ° with respect to the vertical direction or 135 ° with respect to the vertical direction is output.
  • the angles of the filters of the switches 500a to 500d are adjusted according to the polarization angle of the DaaS server unit 102, the twist of the communication line 200, and the like. Specifically, when a photon having a polarization angle of 0 °, 45 °, 135 °, or the like of the DaaS server unit 102 is transmitted, the DaaS server unit 102 having a polarization angle of 0 °, 45 °, 135 °, or the like. It is assumed that the light beams are incident on the switches 500a to 500d at the same angle as the polarization angle in FIG.
  • Each of the switches 500a to 500d is arranged so that when the photon passes through the filter when the direction of the filter is linearly polarized light in the vertical direction or when the filter is linearly polarized light of 135 ° with respect to the vertical direction, It is assumed that the bit value that is the observation result is “1”. Also, each switch 500a-d has a corresponding photon digit when the photon passes through the filter when the direction of the filter is linearly polarized light in the horizontal direction or when it is 45 ° linearly polarized light with respect to the vertical direction. Assume that the bit value that is the observation result of is “0”.
  • Each switch 500a to 500d performs the following process when all the photons transmitted in the process of step S103 are received. That is, each of the switches 500a to 500d transmits the filter direction information, which is information indicating the filter direction of each digit set in the process of step S104, to the DaaS server unit 102 via the communication line 200 (step S105). Therefore, the filter direction information is information indicating the polarization angle (that is, the filter angle) through which the photon passes in accordance with each digit of the bit value. Each of the switches 500a to 500d does not transmit information indicating the observation result in the process of step S104 in the process of step S105.
  • the DaaS server unit 102 performs a comparison process in accordance with an instruction from the administrator unit 101. That is, the DaaS server unit 102 determines, for each digit, whether the polarization angle indicated by the filter direction information transmitted in step S105 matches the polarization angle of the photon transmitted in step S103. Perform a comparison process. Then, in accordance with the instruction from the administrator unit 101, the DaaS server unit 102 transmits to the corresponding switches 500a to 500d digit number information indicating the digits whose bit values match each other based on the result of each comparison process ( Step S106).
  • the DaaS server unit 102 deletes digits that do not match as a result of the respective comparison processes, and generates a bit value string consisting only of the matched digits as a shared secret key with each of the switches 500a to 500d. (Step S107). Also, each of the switches 500a to 500d deletes digits other than the digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106, and converts the bit value string consisting only of the remainder to the DaaS server unit 102.
  • the shared secret key is used (step S108).
  • steps S104, S107, and 108 will be described with a specific example.
  • the random number sequence generated by the DaaS server unit 102 in the process of step S101 is “1011101001”.
  • the polarization angle of the photon transmitted in the process of step S103 is “a” in the vertical direction, “b” in the vertical direction of 135 °, “c” in the horizontal direction, and 45 in the vertical direction. ° is expressed as “d”.
  • the polarization angle of the photon corresponding to the random number sequence generated in the process of step S101 is represented by, for example, “adabadacda”.
  • the switch angle of the switch 500a (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”.
  • the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by “adbccdccda”, for example.
  • the observation result of the switch 500a in the process of step S104 is represented by “10——0—101”. Note that “ ⁇ ” indicates that no observation was made, that is, no photon passed through the filter.
  • the DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the first, second, sixth, eighth, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the first, second, sixth, eighth, ninth, and tenth digits match in the process of step S106 to the switch 500a.
  • the DaaS server unit 102 in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “100101” including the bit values of the first, second, sixth, eighth, ninth, and tenth digits.
  • the switch 500a in the observation result, indicates a bit value string “only the first, second, sixth, eighth, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106.
  • 100101 "is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
  • the switch angle of the switch 500b (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”.
  • the angle of the filter according to the random number sequence generated in the process of step S102 is represented by “bddcadabda”, for example.
  • the observation result of the switch 500b in the process of step S104 is represented by “ ⁇ 0 ⁇ 101-01”. Note that “ ⁇ ” indicates that no observation was made, that is, no photon passed through the filter.
  • the DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the second, fifth, sixth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the second, fifth, sixth, seventh, ninth and tenth digits match to the switch 500b in the process of step S106.
  • the DaaS server unit 102 in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “010101” including the bit values of the second, fifth, sixth, seventh, ninth and tenth digits.
  • the switch 500b has a bit value string “only the second, fifth, sixth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result.
  • "010101” is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
  • the random number sequence generated by the switch 500c in the process of step S102 is “0011111001”.
  • the angle of the filter of the switch 500c (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”.
  • the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by “bdacaaaabda”, for example.
  • the observation result of the switch 500c in the process of step S104 is represented by “ ⁇ 01-1-1-01”. Note that “ ⁇ ” indicates that no observation was made, that is, no photon passed through the filter.
  • the DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the second, third, fifth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the second, third, fifth, seventh, ninth, and tenth digits match to the switch 500c in the process of step S106.
  • the DaaS server unit 102 in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “011101” including the bit values of the second, third, fifth, seventh, ninth and tenth digits. Is a shared secret key with the switch 500c. Further, the switch 500c indicates that the bit value string “only the second, third, fifth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result“ “011101” is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
  • the random number sequence generated by the switch 500d in the process of step S102 is “1111001001”.
  • the switch angle of the switch 500d (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”.
  • the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by, for example, “aaacbdabda”.
  • the observation result of the switch 500d in the process of step S104 is represented by “1-1-1--01-01”. Note that “ ⁇ ” indicates that no observation was made, that is, no photon passed through the filter.
  • the DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the first, third, sixth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the first, third, sixth, seventh, ninth, and tenth digits match to the switch 500d in the process of step S106.
  • the DaaS server unit 102 in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “110101” including the bit values of the first, third, sixth, seventh, ninth and tenth digits. Is a shared secret key with the switch 500d. Further, the switch 500d indicates that the bit value string “only the first, third, sixth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result“ 110101 ”is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
  • the DaaS server unit 102 compares each of the shared secret keys with the switches 500a to 500d according to an instruction from the administrator unit 101, and shares a bit value string consisting of the bit values of the matching digits for the entire secret communication system.
  • a secret key is set (step S109).
  • step S109 the DaaS server unit 102 shares the shared secret key “100101” with the switch 500a, the shared secret key “010101” with the switch 500b, and the shared secret key “011101” with the switch 500c. ”And the shared secret key“ 110101 ”with the switch 500d are compared with each other for each digit, and the bit value of the digit that does not match is erased. Then, the DaaS server unit 102 uses the remaining bit value string as the shared secret key of the entire secret communication system. Specifically, when the DaaS server unit 102 compares each shared secret key with each digit in the process of step S109, the bit values of the first, second, and third digits do not match each other.
  • the DaaS server unit 102 deletes the first, second, and third digits from the bit value sequence that is each shared secret key.
  • the DaaS server unit 102 uses the remaining bit value string “101” based on the fourth, fifth, and sixth bit values as the shared secret key of the entire secret communication system.
  • the DaAS server unit 102 transmits erase digit information indicating the digit of the erased bit value to each of the switches 500a to 500d in accordance with an instruction from the administrator unit 101 (step S110). Therefore, in this example, the erase digit information indicates the first, second, and third digits.
  • the switches 500a to 500d erase the first, second, and third digits of the shared secret key with the DaaS server unit 102 based on the erased digit information transmitted by the DaaS server unit 102 in the process of step S110.
  • the switches 500a to 500d use the remaining bit value string “101” based on the fourth, fifth, and sixth digit bit values as the shared secret key of the entire secret communication system (step S111).
  • the information processing unit 100 and the switches 500a to 500d can share the secret key with less effort and low cost by comparing the generated random number sequence with the received bit value sequence. it can. That is, the shared secret key can be distributed to the information processing unit 100 and the switches 500a to 500d with little effort and low cost. Further, according to the present embodiment, since the secret key is generated based on the polarization angle of the photon using the theory of quantum mechanics, the secret key may be leaked in the communication path of the photon. Absent. Therefore, the communication path between the information processing unit 100 and the switches 500a to 500d can be made highly confidential. Embodiment 2. FIG. Next, a secret communication system according to a second embodiment of the present invention will be described.
  • packets are encrypted with a shared secret key between the information processing unit 100 and the switches 500a-z and between the switches 500a-z, and are transmitted and received with high confidentiality.
  • the shared secret key used in the present embodiment is preferably the shared secret key of the entire confidential communication system generated in the first embodiment, but is a shared secret key generated by another method. Also good.
  • FIG. 3 is a block diagram illustrating a configuration example of the confidential communication system according to the second embodiment of this invention.
  • the same reference numerals as those in FIG. 1 are given to the same components as those of the confidential communication system of the first embodiment of the present invention shown in FIG. The description is omitted.
  • the confidential communication system includes an information processing unit 100 and switches 500a-z.
  • the information processing unit 100 is connected to the switches 500a to 500z via the communication line 200, respectively.
  • the switches 500a to z are connected to the LAN / WAN 300.
  • the switches 500a to 500z are connected to client computers 400a to 400z that transmit / receive packetized confidential information to / from each other.
  • FIG. 4 is a flowchart showing an operation in which the information processing unit 100 provides hash function information to each of the switches 500a-z.
  • the information processing unit 100 generates a hash function table (step S201).
  • the DaaS server unit 102 generates a hash function table in accordance with instructions from the administrator unit 101.
  • the hash function table is a table in which a large number of hash functions and identifiers for identifying them are associated in a table format.
  • the hash function table generation method will be described more specifically.
  • the DaaS server unit 102 obtains one hash function from a storage unit (not shown) in which a large number of hash functions are stored according to instructions from the administrator unit 101. Read it out. Further, the DaaS server unit 102 generates a random number in accordance with an instruction from the administrator unit 101.
  • the DaaS server unit 102 associates the read hash function with the generated random number in a table format to form a hash function table.
  • the random number generated by the DaaS server unit 102 has a function as an identifier for identifying a number of hash functions from each other.
  • the information processing unit 100 (more specifically, the DaaS server unit 102) encrypts the hash function table generated in the process of step S201 with the bit value string “101” of the shared secret key of the entire secret communication system,
  • the data is transmitted to the switches 500a to 500z (step S202).
  • Each switch 500a-z decrypts the transmitted hash function table with the bit value string “101” of the shared secret key of the entire secret communication system, and stores it in the respective storage means (not shown).
  • FIG. 5 is a flowchart showing an operation in which each switch 500a-z generates a one-time pad shared secret key.
  • each of the switches 500a to 500z calculates a hash value based on the hash function table and the bit value string “101” of the shared secret key of the entire secret communication system (step S301).
  • each of the switches 500a to 500z includes, in each hash function in the hash function table transmitted in the process of step S202 shown in FIG. To calculate the hash values.
  • Each switch 500a-z determines the hash value calculated in the process of step S301 as the one-time pad shared secret key (step S302).
  • Packets transmitted / received between the switches 500a-z are, for example, packets transmitted / received between the client computers 400a-z.
  • FIG. 6 is a sequence diagram showing an operation in which each switch 500a-z transmits and receives a packet between each other.
  • the switch 500a transmits a received packet to the switch 500b will be described. Therefore, only the switches 500a and 500b among the switches 500a to 500z are shown in FIG.
  • the switch 500a receives the packet transmitted to the switch 500b (step S401).
  • the packet received by the switch 500a in the process of step S401 is, for example, a packet transmitted from the client computer 400a connected to the switch 500a to the client computer 400b connected to the switch 500b.
  • the switch 500a transmits packet information indicating the packet information received in the process of step S401 to the information processing unit 100 via the communication line 200 (step S402).
  • the packet information transmitted in step S402 includes at least information indicating the transmission source and information indicating the transmission destination.
  • the information indicating the transmission source is, for example, an IP (Internet Protocol) address or a MAC (Media Access Control) address of the packet transmission source device.
  • the information indicating the transmission destination is, for example, a telephone number, an e-mail address, a URL (Uniform Resource Locator), or the like of a packet transmission destination device.
  • the packet information may include internal transfer setting information including topology information and flow entry information.
  • the topology information is information representing the connection state of other switches connected to the respective ports of the switches 500a to 500z when the switches 500a to 500z are PF switches.
  • the flow entry information is flow entry information stored in each switch 500a-z.
  • the information processing unit 100 that has received the packet information transmitted in step S402 performs address resolution and network resolution (step S404). That is, the information processing unit 100 performs route calculation.
  • the information processing unit 100 provides information indicating a packet transmission destination to a DNS (Domain Name System) function unit (not shown), for example, and obtains an address (for example, an IP address) of the packet transmission destination. To do. Then, the information processing unit 100 specifies the transmission path of the packet based on the IP address of the switch 500a and the IP address of the transmission destination of the packet. In this example, it is assumed that the transmission path is specified so that the packet is transmitted from the switch 500a to the switch 500b.
  • DNS Domain Name System
  • address resolution and network resolution methods may be other methods as long as the packet transmission route is specified as in this example.
  • the information processing unit 100 associates the flow table, the MPLS (Multi-Protocol Label Switching) label, and the hash function table, and transmits them to the switches 500a to 500z (steps S404 and S405).
  • the flow table transmitted in the processing of steps S404 and S405 is a table in which a series of routes (transmission routes) of packets received by the switch 500a in the processing of step S401 are specified.
  • the MPLS label is an MPLS label corresponding to the transmission path of the packet.
  • the MPLS label may be generated by the DaaS server unit 102 or may be generated by a dedicated device. For example, random numbers are used for the hash function table, the MPLS label, and the flow table.
  • the information processing unit 100 (specifically, for example, the DaaS server unit 102) stores the flow table, the MPLS label, and the hash function table in association with each other in a storage unit (not shown) (step S406). Further, the switches 500a to 500z store the flow table, the MPLS label, and the hash function table transmitted by the information processing unit 100 in the processes of steps S404 and S405 in association with each other in a storage unit (not shown) (steps S407, S405). S408).
  • the switch 500a that has received the packet in the process of step S401 randomly selects a hash function to be used for the one-time pad shared secret key using, for example, a random number from the hash functions included in the hash function table stored in the process of step S407. Select Then, the switch 500a applies the bit value string “101” of the shared secret key of the entire secret communication system to the selected hash function, calculates the hash value, and encrypts the packet (step S409).
  • the switch 500a encapsulates the packet encrypted in the process of step S409 (step S410). Specifically, the switch 500a encapsulates with the identifier associated with the hash function used in the process of step S409 in the hash function table and the MPLS label associated with the hash function table. Note that the switch 500a encapsulates the identifier and the MPLS label so as to be clearly indicated in the process of step S410.
  • the switch 500a transmits the packet encapsulated in the process of step S410 (step S411).
  • the packet transmitted in the process of step S411 is transferred from the switch 500a to the switch 500b based on the header of the MPLS label used for encapsulation.
  • the switch 500b When the switch 500b receives the packet transmitted by the switch 500a in step S411, the switch 500b decrypts the received packet with the one-time pad shared secret key (step S412). Specifically, the switch 500b releases the encapsulation of the packet based on the MPLS label and the identifier of the received packet. Then, the switch 500b applies the bit value string “101” of the shared secret key of the entire secret communication system to the hash function associated with the identifier in the hash function table stored in the storage unit, and the hash value And the packet is decoded. For example, the switch 500b transmits the decrypted packet to the connected client computer 400b.
  • the switch 500b transmits a BYE command (session end request) to the information processing unit 100 (step S413).
  • the information processing unit 100 (specifically, for example, the DaaS server unit 102) performs the following process based on the reception of the session end request transmitted in the process of step S413. That is, the information processing unit 100 deletes the flow table, the MPLS label, and the hash function table stored in the storage unit in the process of step S406 from the storage unit (step S414).
  • the information processing unit 100 (specifically, for example, the DaaS server unit 102) performs the following processing as steps S415 and S416. That is, the information processing unit 100 transmits to the switches 500a to 500z an instruction to delete the flow table, the MPLS label, and the hash function table stored in the storage unit in the processing of steps S407 and S408 from the storage unit (step S415, S416).
  • the switches 500a to 500z perform the following process according to the instruction transmitted by the information processing unit 100 in the processes of steps S415 and S416. In other words, the switches 500a to 500z delete the flow table, MPLS label, and hash function table stored in the storage unit in the processes of steps S407 and S408 from the storage unit (steps S417 and S418).
  • the one-time pad shared secret key can be distributed to each switch 500a-z included in the secret communication system using the secret key of the entire secret communication system. Therefore, it is possible to distribute a highly confidential one-time pad shared secret key in a short time to many information transmission apparatuses such as the switches 500a to 500z.
  • the one-time pad shared secret key is distributed using MPLS, it is compatible with the facilities of the current carrier. Therefore, since the present invention can be implemented by diverting the existing facilities of the telecommunications carrier, the telecommunications carrier can implement the present invention at low cost.
  • the packet destination switch 500b when the packet destination switch 500b receives the packet, it transmits a session end request to the information processing unit 100. Then, in response to receiving the session end request, the information processing unit 100 deletes information from the own unit and each of the switches 500a-z. Therefore, it is possible to satisfactorily reduce the risk of information leakage.
  • Embodiment 3. a secret communication system according to a third embodiment of the present invention will be described. Since the configuration of the confidential communication system of the present embodiment is the same as that of the first embodiment shown in FIG. 1, the same reference numerals as those in FIG. As shown in FIG.
  • the confidential communication system includes a plurality of switches (information transmission apparatuses) 500a to 500d connected to a communication network 300, and each switch 500a to 500d.
  • Each includes an information processing unit 100 connected by a communication line 200.
  • the information processing unit 100 and each of the switches 500a to 500d each generate a communication line connection shared secret key.
  • the information processing unit 100 compares each of the communication line connection shared secret keys with each other, generates the entire shared secret key of the information processing unit 100 and each of the switches 500a to 500d based on the comparison result, and compares The result is transmitted to each switch 500a-d.
  • Each of the switches 500a to 500d generates the entire shared secret key of the information processing unit 100 and each of the switches 500a to 500d based on the transmitted comparison result and the communication line connection shared secret key.
  • communication between the switches 500a to 500d connected to the communication network 300 can be made highly confidential with less effort and low cost.
  • Each of the information transmission devices is based on the transmitted comparison result and the communication line connection shared secret key.
  • a secret communication system characterized by generating an entire shared secret key for the information processing unit and each information transmission device.
  • the confidential communication system according to supplementary note 1, wherein each of the information processing unit and the information transmission device generates a communication line connection shared secret key based on a quantum cryptography technique.
  • the information processing unit delivers a hash function table including a plurality of hash functions respectively associated with identifiers to each of the information transmission apparatuses, and the information transmission apparatuses transmit and receive packets to and from each other.
  • the information transmission device on the packet transmission side encrypts the packet using a hash value obtained by applying the entire shared secret key to one hash function among a plurality of hash functions included in the hash function table, An identifier associated with one hash function is clearly specified, and the encrypted packet is transmitted.
  • the information transmission apparatus on the reception side of the packet is clearly specified in the packet.
  • the encrypted packet is decrypted using the hash value obtained by applying the whole shared secret key to the one hash function. Secure communications system according to Appendix 1 or Appendix 2, characterized in that.
  • the information processing unit encrypts and delivers a hash function table including a plurality of hash functions to each of the information transmission apparatuses with the entire shared secret key, and each of the information transmission apparatuses 4.
  • the confidential communication system according to appendix 3, wherein the hash function table encrypted and distributed is decrypted with the entire shared secret key.
  • the information transmission apparatus on the packet reception side requests the information processing unit to end the session, and the information processing unit transmits the packet stored in the unit.
  • the information corresponding to the transmission is erased, and each information transmission apparatus is requested to erase the information according to the transmission of the packet, and each information transmission apparatus transmits the packet in response to the information erasure request.
  • the confidential communication system according to supplementary note 3 or supplementary note 4, wherein information according to the above is deleted.
  • the confidential communication system according to any one of Supplementary note 1 to Supplementary note 5, wherein a communication line connecting the information processing unit and each of the information transmission apparatuses is an optical fiber.
  • Appendix 7 Each of a plurality of information transmission devices connected to a communication network and an information processing unit connected to each information transmission device via a communication line respectively generate a communication line connection shared secret key.
  • a global shared secret key generation unit side step for generating an overall global shared secret key of the information processing unit and each information transmission device based on the comparison result based on the result of the comparison step;
  • a comparison result transmission step in which the processing unit transmits the result of the comparison in the comparison step to each information transmission device;
  • Each of the information transmission devices generates an overall shared secret key between the information processing unit and each information transmission device based on the transmitted comparison result and the communication line connection shared secret key
  • a secret key distribution method in a secret communication system comprising: a secret key generation device side step.

Abstract

In order to enhance confidentiality in communication between information transmission devices such as switches in a communication network with little effort and at low cost, this confidential communication system is provided with a plurality of switches (500a-d) connected to a LAN/WAN (300) and an information processing unit (100) connected to each of the switches (500a-d) by a communication line (200). The information processing unit (100) and each of the switches (500a-d) respectively generate a mutually shared secret key. The information processing unit (100) compares each of the shared secret keys with each other, generates a general shared secret key on the basis of the result of comparison, and transmits the result of comparison to each of the switches (500a-d). Each of the switches (500a-d) generates a general shared secret key on the basis of the transmitted result of comparison and the secret keys shared with the information processing unit (100).

Description

機密通信システムおよび機密通信システムにおける秘密鍵配送方法Secret communication system and secret key distribution method in secret communication system
　本発明は、機密通信が行われる機密通信システムおよび機密通信システムにおける秘密鍵配送方法に関する。 The present invention relates to a secret communication system in which secret communication is performed and a secret key distribution method in the secret communication system.
　サーバと、当該サーバにそれぞれ接続された複数のスイッチとを含む情報処理システムがある。そのような情報処理システムでは、各スイッチにそれぞれクライアントコンピュータが接続される。そして、各クライアントコンピュータ間で機密通信が行われる場合には、共有秘密鍵が用いられて情報が暗号化される。 There is an information processing system including a server and a plurality of switches respectively connected to the server. In such an information processing system, a client computer is connected to each switch. When confidential communication is performed between the client computers, the shared secret key is used to encrypt the information.
　例えば、特許文献１には、いずれも通信ネットワークに接続された一方の鍵共有装置と他方の鍵共有装置とがワンタイムパッド鍵を共有することが記載されている。また、特許文献２には、秘密鍵に量子暗号を用いることが記載されている。 For example, Patent Document 1 describes that one key sharing apparatus and the other key sharing apparatus connected to a communication network share a one-time pad key. Patent Document 2 describes the use of quantum cryptography as a secret key.
特開２００７－１８０７５８号公報JP 2007-180758 A 特表２０１３－５２９８０４号公報Special table 2013-529804 gazette 国際公開第２０１３／０１４７３４号International Publication No. 2013/014734
　しかし、機密情報の通信において、特許文献１に記載されているワンタイムパッド鍵や特許文献２に記載されている量子暗号を用いるために、情報の送信側と受信側とは、秘密鍵を共有しなければならない。具体的には、情報を送受信する各クライアントコンピュータ、より具体的には各クライアントコンピュータが接続されている各スイッチが、秘密鍵を共有しなければならない。各装置に秘密鍵を共有させるために、特許文献１に記載されているワンタイムパッド鍵や特許文献２に記載されている量子暗号を用いた秘密鍵は、サーバおよび各スイッチに記載されて物理的に輸送され、各装置に人手で入力されている。 However, since the one-time pad key described in Patent Document 1 and the quantum cryptography described in Patent Document 2 are used in the communication of confidential information, the information transmitting side and the receiving side share a secret key. Must. Specifically, each client computer that transmits and receives information, more specifically, each switch to which each client computer is connected must share a secret key. In order for each device to share a secret key, a one-time pad key described in Patent Document 1 or a secret key using quantum cryptography described in Patent Document 2 is physically stored in a server and each switch. And are manually entered into each device.
　したがって、秘密鍵の輸送や各装置への入力に手間および費用を要するという問題がある。また、秘密鍵が漏えいしてしまうおそれがあるという問題がある。そして、クライアントコンピュータが接続されたスイッチが含まれるＬＡＮ（Ｌｏｃａｌ　Ａｒｅａ　Ｎｅｔｗｏｒｋ）やＷＡＮ（Ｗｉｄｅ　Ａｒｅａ　Ｎｅｔｗｏｒｋ）の規模が大きくなるほど、これらの問題は大きくなる。つまり、スイッチの数が多くなるほど、これらの問題は大きくなる。 Therefore, there is a problem that labor and cost are required for transporting the secret key and inputting it to each device. There is also a problem that the secret key may be leaked. These problems increase as the scale of a LAN (Local Area Network) or WAN (Wide Area Network) including a switch to which a client computer is connected increases. In other words, these problems become larger as the number of switches increases.
　そこで、本発明は、少ない手間および低コストで、通信ネットワークに接続されたスイッチ等の情報伝送装置間の通信を高機密化することができる機密通信システムおよび機密通信システムにおける秘密鍵配送方法を提供することを目的とする。 Accordingly, the present invention provides a secret communication system and a secret key distribution method in a secret communication system that can make communication between information transmission apparatuses such as switches connected to a communication network highly confidential with less effort and low cost. The purpose is to do.
　本発明による機密通信システムは、通信ネットワークに接続された複数の情報伝送装置と、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとを備え、情報処理ユニットと情報伝送装置のそれぞれとは、通信回線接続共有秘密鍵をそれぞれ生成し、情報処理ユニットは、通信回線接続共有秘密鍵のそれぞれを互いに比較し、当該情報処理ユニットと各情報伝送装置との全体の共有秘密鍵を比較の結果に基づいて生成し、比較の結果を各情報伝送装置に送信し、情報伝送装置のそれぞれは、送信された比較の結果と通信回線接続共有秘密鍵とに基づいて、情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成することを特徴とする。 A confidential communication system according to the present invention includes a plurality of information transmission devices connected to a communication network, and information processing units each connected to the information transmission devices via a communication line, the information processing unit and the information transmission device Each of the communication line connection shared secret keys is generated, and the information processing unit compares each of the communication line connection shared secret keys with each other, and the entire shared secret key between the information processing unit and each information transmission device. Is generated based on the comparison result, and the comparison result is transmitted to each information transmission device, and each of the information transmission devices is configured to process the information processing unit based on the transmitted comparison result and the communication line connection shared secret key. And an overall shared secret key for each information transmission apparatus.
　本発明による機密通信システムにおける秘密鍵配送方法は、通信ネットワークに接続された複数の情報伝送装置のそれぞれと、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとが、通信回線接続共有秘密鍵をそれぞれ生成する通信回線接続共有秘密鍵生成ステップと、情報処理ユニットが、通信回線接続共有秘密鍵生成ステップで生成された通信回線接続共有秘密鍵のそれぞれを互いに比較する比較ステップと、情報処理ユニットが、比較ステップの結果に基づいて、当該情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を比較の結果に基づいて生成する全体共有秘密鍵生成ユニット側ステップと、情報処理ユニットが、比較ステップにおける比較の結果を各情報伝送装置に送信する比較結果送信ステップと、情報伝送装置のそれぞれが、送信された比較の結果と通信回線接続共有秘密鍵とに基づいて、情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成する全体共有秘密鍵生成装置側ステップとを含むことを特徴とする。 In the secret key distribution method in the secret communication system according to the present invention, each of the plurality of information transmission devices connected to the communication network and each of the information processing units connected to each information transmission device by a communication line communicate with each other. A communication line connection shared secret key generation step for generating a line connection shared secret key, and a comparison step in which the information processing unit compares each of the communication line connection shared secret keys generated in the communication line connection shared secret key generation step with each other. And an overall shared secret key generation unit side step in which the information processing unit generates the entire overall shared secret key of the information processing unit and each information transmission apparatus based on the comparison result based on the result of the comparison step; The information processing unit transmits the comparison result in the comparison step to each information transmission device. And the information transmission device respectively generate an overall shared secret key for the information processing unit and each information transmission device based on the transmitted comparison result and the communication line connection shared secret key. And a secret key generation device side step.
　本発明によれば、少ない手間および低コストで、通信ネットワークに接続されたスイッチ等の情報伝送装置間の通信を高機密化することができる。 According to the present invention, communication between information transmission apparatuses such as switches connected to a communication network can be made highly confidential with less effort and low cost.
本発明の第１の実施形態の機密通信システムの構成例を示すブロック図である。It is a block diagram which shows the structural example of the confidential communication system of the 1st Embodiment of this invention. 情報処理ユニットとスイッチとがそれぞれ共有する共有秘密鍵を生成する動作を示すシーケンス図である。It is a sequence diagram which shows the operation | movement which produces | generates the shared secret key which an information processing unit and a switch each share. 本発明の第２の実施形態の機密通信システムの構成例を示すブロック図である。It is a block diagram which shows the structural example of the confidential communication system of the 2nd Embodiment of this invention. 情報処理ユニットが、各スイッチにハッシュ関数の情報を提供する動作を示すフローチャートである。It is a flowchart which shows the operation | movement in which an information processing unit provides the information of a hash function to each switch. 各スイッチがワンタイムパッド共有秘密鍵を生成する動作を示すフローチャートである。It is a flowchart which shows the operation | movement which each switch produces | generates a one time pad shared secret key. 各スイッチが互いの間でパケットを送受信する動作を示すシーケンス図である。It is a sequence diagram which shows the operation | movement which each switch transmits / receives a packet between each other.
実施形態１．
　本発明の第１の実施形態について、図面を参照して説明する。図１は本発明の第１の実施形態の機密通信システムの構成例を示すブロック図である。図１に示すように、本発明の第１の実施形態の機密通信システムは、情報処理ユニット１００、およびスイッチ（情報伝送装置）５００ａ～ｄを含む。情報処理ユニット１００は、スイッチ５００ａ～ｄと、それぞれ通信回線２００を介して接続されている。スイッチ５００ａ～ｄは、ＬＡＮまたはＷＡＮ（以下、ＬＡＮ／ＷＡＮ（通信ネットワーク）という）３００に接続されている。 Embodiment 1. FIG.
A first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration example of a confidential communication system according to the first embodiment of this invention. As shown in FIG. 1, the confidential communication system according to the first embodiment of the present invention includes an information processing unit 100 and switches (information transmission apparatuses) 500a to 500d. The information processing unit 100 is connected to the switches 500a to 500d via the communication line 200, respectively. The switches 500a to 500d are connected to a LAN or WAN (hereinafter referred to as LAN / WAN (communication network)) 300.
　また、スイッチ５００ａ～ｄには、パケット化された機密情報を情報処理ユニット１００と送受信するクライアントコンピュータ４００ａ～ｄ（図１において図示せず）がそれぞれ接続されている。そして、スイッチ５００ａ～ｄは、情報処理ユニット１００とクライアントコンピュータ４００ａ～ｄとの間でパケットが適切な通信経路を通って送受信されるように当該パケットを中継する。スイッチ５００ａ～ｄは、ＯｐｅｎＦｌｏｗ（登録商標）に対応したＰＦ（Ｐｒｏｇｒａｍｍａｂｌｅ　Ｆｌｏｗ）スイッチであることが好ましいが、以下に述べる機能を有していれば他のスイッチであってもよい。なお、通信回路２００は、例えば、光ファイバ等の光通信回線によって実現されるが、光子を伝送可能であれば他の通信媒体によって実現されてもよいし、無線通信回線であってもよい。また、図１には、４台のスイッチ５００ａ～ｄが例示されているが、スイッチ５００は４台未満であってもよいし、５台以上であってもよい。また、各スイッチ５００ａ～ｄにそれぞれ複数のクライアントコンピュータが接続されていてもよいし、他の装置が接続されていてもよい。 Further, client computers 400a to 400d (not shown in FIG. 1) for transmitting and receiving packetized confidential information to and from the information processing unit 100 are connected to the switches 500a to 500d, respectively. The switches 500a to 500d relay the packets so that the packets are transmitted and received through the appropriate communication path between the information processing unit 100 and the client computers 400a to 400d. The switches 500a to 500d are preferably PF (Programmable Flow) switches corresponding to OpenFlow (registered trademark), but may be other switches as long as they have the functions described below. The communication circuit 200 is realized by, for example, an optical communication line such as an optical fiber, but may be realized by another communication medium or a wireless communication line as long as photons can be transmitted. 1 illustrates four switches 500a to 500d, but the number of switches 500 may be less than four, or may be five or more. A plurality of client computers may be connected to each of the switches 500a to 500d, or other devices may be connected.
　図１に示す例では、情報処理ユニット１００は、アドミニストレータ部１０１、ＤａａＳ（Ｄｅｓｋｔｏｐ　ａｓ　ａ　Ｓｅｒｖｉｃｅ）サーバ部１０２、および単一光子発生部１０３を含む。単一光子発生部１０３は、ＤａａＳサーバ部１０２の指示に従って、所定の角度に直線偏光された光子を生成する。ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、スイッチ５００ａ～ｄやクライアントコンピュータ４００ａ～ｄと情報を送受信する。また、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、スイッチ５００ａ～ｄに、単一光子発生部１０３が生成した光子を送信する。 In the example shown in FIG. 1, the information processing unit 100 includes an administrator unit 101, a DaAS (Desktop as a Service) server unit 102, and a single photon generation unit 103. The single photon generation unit 103 generates photons linearly polarized at a predetermined angle in accordance with an instruction from the DaaS server unit 102. The DaS server unit 102 transmits and receives information to and from the switches 500a to 500d and the client computers 400a to 400d in accordance with instructions from the administrator unit 101. Further, the DaaS server unit 102 transmits the photons generated by the single photon generation unit 103 to the switches 500a to 500d in accordance with instructions from the administrator unit 101.
　なお、アドミニストレータ部１０１およびＤａａＳサーバ部１０２は、それぞれが別体のコンピュータによって実現されてもよいし、１台のコンピュータによって実現されてもよい。また、情報処理ユニット１００が単一光子発生部１０３を含む代わりに、ＤａａＳサーバ部１０２が、所定の角度に直線偏光された光子を生成する機能を有していてもよい。 Note that the administrator unit 101 and the DaaS server unit 102 may be realized by separate computers, or may be realized by a single computer. Further, instead of the information processing unit 100 including the single photon generation unit 103, the DaaS server unit 102 may have a function of generating photons linearly polarized at a predetermined angle.
　図２は、情報処理ユニット１００とスイッチ５００ａ～ｄとがそれぞれ共有する共有秘密鍵を生成する動作を示すシーケンス図である。図２に示す例では、ＢＢ８４の方式に基づいて量子暗号が各スイッチ５００ａ～ｄに配送される。図２に示すように、ＤａａＳサーバ部１０２および各スイッチ５００ａ～ｄは、「０」または「１」のビット値がランダムに並べられた互いに同じ桁数の乱数列をそれぞれ生成する（ステップＳ１０１，Ｓ１０２）。なお、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って自ら乱数列を生成してもよいし、図示しない乱数発生装置が発生した乱数列の提供を受けてもよい。 FIG. 2 is a sequence diagram showing an operation of generating a shared secret key shared by the information processing unit 100 and the switches 500a to 500d. In the example shown in FIG. 2, the quantum cipher is delivered to each of the switches 500a to 500d based on the BB84 method. As shown in FIG. 2, the DaS server unit 102 and each of the switches 500a to 500d respectively generate a random number sequence having the same number of digits in which bit values of “0” or “1” are randomly arranged (step S101, S102). The DaaS server unit 102 may generate a random number sequence in accordance with an instruction from the administrator unit 101, or may receive provision of a random number sequence generated by a random number generator (not shown).
　ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、ステップＳ１０１の処理で生成した乱数列に従った光子を通信回線２００を介してスイッチ５００ａ～ｄに送信する（ステップＳ１０３）。具体的には、ＤａａＳサーバ部１０２は、当該乱数列においてビット値「１」の桁に応じた光子を送信する場合に、垂直方向（つまり０°）の直線偏光または垂直方向に対して１３５°の直線偏光のいずれかをランダムに選択する。そして、ＤａａＳサーバ部１０２は、ステップＳ１０３の処理で、選択した直線偏光の光子を送信する。 The DaAS server unit 102 transmits photons according to the random number sequence generated in the process of step S101 to the switches 500a to 500d via the communication line 200 according to the instruction of the administrator unit 101 (step S103). Specifically, when transmitting the photon corresponding to the digit of the bit value “1” in the random number sequence, the DaaS server unit 102 is 135 ° with respect to the linearly polarized light in the vertical direction (that is, 0 °) or the vertical direction. One of the linearly polarized light is randomly selected. Then, the DaaS server unit 102 transmits the selected linearly polarized photon in the process of step S103.
　また、ＤａａＳサーバ部１０２は、当該乱数列においてビット値「０」の桁に応じた光子を送信する場合に、水平方向（つまり９０°）の直線偏光または垂直方向に対して４５°の直線偏光のいずれかをランダムに選択する。そして、ＤａａＳサーバ部１０２は、ステップＳ１０３の処理で、選択した直線偏光の光子を送信する。 Further, when transmitting the photon corresponding to the digit of the bit value “0” in the random number sequence, the DaaS server unit 102 linearly polarized light in the horizontal direction (that is, 90 °) or linearly polarized light of 45 ° with respect to the vertical direction. One of the above is selected at random. Then, the DaaS server unit 102 transmits the selected linearly polarized photon in the process of step S103.
　各スイッチ５００ａ～ｄは、ステップＳ１０３の処理でＤａａＳサーバ部１０２によって送信された光子を受信すると、受信した光子の偏光状態を観測する（ステップＳ１０４）。具体的には、例えば、ステップＳ１０２の処理で生成された乱数列に従って、スイッチ５００ａ～ｄに内蔵されている光子受信機（図示せず）が有するフィルタ（図示せず）に、ステップＳ１０３の処理で送信された光子を入射させる。フィルタは、例えば、方解石の結晶である。光子を当該フィルタに入射させる場合に、各スイッチ５００ａ～ｄは、ステップＳ１０２の処理でそれぞれ生成した乱数列に従って、フィルタの向きを異ならせる。 Each switch 500a to 500d receives the photon transmitted by the DaaS server unit 102 in the process of step S103, and observes the polarization state of the received photon (step S104). Specifically, for example, according to the random number sequence generated in step S102, a filter (not shown) included in a photon receiver (not shown) built in switches 500a to 500d is processed in step S103. The photon transmitted in is made incident. The filter is, for example, a calcite crystal. When causing photons to enter the filter, each of the switches 500a to 500d changes the direction of the filter according to the random number sequence generated in the process of step S102.
　乱数列に従ってフィルタの向きを異ならせるとは、例えば、当該乱数列においてビット値が「１」である桁に応じた光子を受信する場合には、垂直方向の直線偏光または水平方向の直線偏光の光子が出力されるように、フィルタの向きを設定する。また、例えば、当該乱数列においてビット値が「０」である桁に応じた光子を受信する場合には、垂直方向に対して４５°または垂直方向に対して１３５°の直線偏光の光子が出力されるように、フィルタの向きを設定する。なお、各スイッチ５００ａ～ｄのフィルタの角度は、ＤａａＳサーバ部１０２の偏光角度や、通信回線２００の捻じれ等に応じて調整されているとする。具体的には、ＤａａＳサーバ部１０２の偏光角度が０°や４５°、１３５°等である光子が送信された場合には、偏光角度が０°や４５°、１３５°等のＤａａＳサーバ部１０２における偏光角度と同じ角度で各スイッチ５００ａ～ｄに入射するものとする。 Differentiating the direction of the filter according to the random number sequence means that, for example, when receiving a photon corresponding to a digit whose bit value is “1” in the random number sequence, the linearly polarized light in the vertical direction or the linearly polarized light in the horizontal direction The direction of the filter is set so that photons are output. Also, for example, when receiving a photon corresponding to a digit whose bit value is “0” in the random number sequence, a linearly polarized photon of 45 ° with respect to the vertical direction or 135 ° with respect to the vertical direction is output. Set the filter orientation to be Note that the angles of the filters of the switches 500a to 500d are adjusted according to the polarization angle of the DaaS server unit 102, the twist of the communication line 200, and the like. Specifically, when a photon having a polarization angle of 0 °, 45 °, 135 °, or the like of the DaaS server unit 102 is transmitted, the DaaS server unit 102 having a polarization angle of 0 °, 45 °, 135 °, or the like. It is assumed that the light beams are incident on the switches 500a to 500d at the same angle as the polarization angle in FIG.
　そして、各スイッチ５００ａ～ｄは、フィルタの向きが垂直方向の直線偏光である場合、または垂直方向に対して１３５°の直線偏光である場合に光子がフィルタを通過したときに、光子の当該桁の観測結果であるビット値が「１」であるとする。また、各スイッチ５００ａ～ｄは、フィルタの向きが水平方向の直線偏光である場合、または垂直方向に対して４５°の直線偏光である場合に光子がフィルタを通過したときに、光子の当該桁の観測結果であるビット値が「０」であるとする。 Each of the switches 500a to 500d is arranged so that when the photon passes through the filter when the direction of the filter is linearly polarized light in the vertical direction or when the filter is linearly polarized light of 135 ° with respect to the vertical direction, It is assumed that the bit value that is the observation result is “1”. Also, each switch 500a-d has a corresponding photon digit when the photon passes through the filter when the direction of the filter is linearly polarized light in the horizontal direction or when it is 45 ° linearly polarized light with respect to the vertical direction. Assume that the bit value that is the observation result of is “0”.
　各スイッチ５００ａ～ｄは、ステップＳ１０３の処理で送信された光子をすべて受信した場合に、以下に示す処理を行う。すなわち、各スイッチ５００ａ～ｄは、ステップＳ１０４の処理で設定した各桁のフィルタの向きを示す情報であるフィルタ方向情報を通信回線２００を介してＤａａＳサーバ部１０２に送信する（ステップＳ１０５）。したがって、フィルタ方向情報は、ビット値の各桁に応じて、光子が通過する偏光角度（つまり、フィルタの角度）を示す情報である。なお、各スイッチ５００ａ～ｄは、ステップＳ１０５の処理で、ステップＳ１０４の処理における観測結果を示す情報を送信しない。 Each switch 500a to 500d performs the following process when all the photons transmitted in the process of step S103 are received. That is, each of the switches 500a to 500d transmits the filter direction information, which is information indicating the filter direction of each digit set in the process of step S104, to the DaaS server unit 102 via the communication line 200 (step S105). Therefore, the filter direction information is information indicating the polarization angle (that is, the filter angle) through which the photon passes in accordance with each digit of the bit value. Each of the switches 500a to 500d does not transmit information indicating the observation result in the process of step S104 in the process of step S105.
　ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、比較処理を行う。すなわち、ＤａａＳサーバ部１０２は、ステップＳ１０５の処理で送信されたフィルタ方向情報によって示される偏光角度とステップＳ１０３の処理で送信した光子の偏光角度とが合致するか否かを各桁ごとに判定する比較処理を行う。そして、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、対応するスイッチ５００ａ～ｄに、それぞれの比較処理の結果に基づいて互いのビット値が合致した桁を示す桁番号情報をそれぞれ送信する（ステップＳ１０６）。 The DaaS server unit 102 performs a comparison process in accordance with an instruction from the administrator unit 101. That is, the DaaS server unit 102 determines, for each digit, whether the polarization angle indicated by the filter direction information transmitted in step S105 matches the polarization angle of the photon transmitted in step S103. Perform a comparison process. Then, in accordance with the instruction from the administrator unit 101, the DaaS server unit 102 transmits to the corresponding switches 500a to 500d digit number information indicating the digits whose bit values match each other based on the result of each comparison process ( Step S106).
　ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、それぞれの比較処理の結果合致しなかった桁を消去し、合致した桁のみからなるビット値列をスイッチ５００ａ～ｄのそれぞれとの共有秘密鍵とする（ステップＳ１０７）。また、各スイッチ５００ａ～ｄは、ステップＳ１０６の処理でＤａａＳサーバ部１０２から送信された桁番号情報によって示される桁以外の桁を消去し、残部のみからなるビット値列をＤａａＳサーバ部１０２との共有秘密鍵とする（ステップＳ１０８）。 In accordance with an instruction from the administrator unit 101, the DaaS server unit 102 deletes digits that do not match as a result of the respective comparison processes, and generates a bit value string consisting only of the matched digits as a shared secret key with each of the switches 500a to 500d. (Step S107). Also, each of the switches 500a to 500d deletes digits other than the digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106, and converts the bit value string consisting only of the remainder to the DaaS server unit 102. The shared secret key is used (step S108).
　ステップＳ１０４，Ｓ１０７，１０８における処理を具体例を挙げて説明する。例えば、ＤａａＳサーバ部１０２がステップＳ１０１の処理で生成した乱数列が「１０１１１０１００１」であったとする。ここで、ステップＳ１０３の処理で送信された光子の偏光角度を、垂直方向を「ａ」、垂直方向に対して１３５°を「ｂ」、水平方向を「ｃ」、および垂直方向に対して４５°を「ｄ」として表す。そうすると、ステップＳ１０１の処理で生成された乱数列に応じた光子の偏光角度はそれぞれ、例えば、「ａｄａｂａｄａｃｄａ」で表される。 The processing in steps S104, S107, and 108 will be described with a specific example. For example, it is assumed that the random number sequence generated by the DaaS server unit 102 in the process of step S101 is “1011101001”. Here, the polarization angle of the photon transmitted in the process of step S103 is “a” in the vertical direction, “b” in the vertical direction of 135 °, “c” in the horizontal direction, and 45 in the vertical direction. ° is expressed as “d”. Then, the polarization angle of the photon corresponding to the random number sequence generated in the process of step S101 is represented by, for example, “adabadacda”.
　また、スイッチ５００ａがステップＳ１０２の処理で生成した乱数列が「１００１１０１１０１」であるとする。ステップＳ１０３の処理で光子が送信されたときのスイッチ５００ａのフィルタの角度（フィルタ方向情報が示す角度）を、垂直方向を「ａ」、垂直方向に対して１３５°を「ｂ」、水平方向を「ｃ」、および垂直方向に対して４５°を「ｄ」として表す。そうすると、ステップＳ１０２の処理で生成された乱数列に応じたフィルタの角度はそれぞれ、例えば、「ａｄｂｃｃｄｃｃｄａ」で表される。そして、ステップＳ１０４の処理におけるスイッチ５００ａの観測結果は、「１０―――０－１０１」で表される。なお、「－」は、観測しなかった、つまり光子がフィルタを通過しなかったことを表す。 Also, assume that the random number sequence generated by the switch 500a in step S102 is “1001101101”. When the photon is transmitted in the process of step S103, the switch angle of the switch 500a (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”. Then, the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by “adbccdccda”, for example. Then, the observation result of the switch 500a in the process of step S104 is represented by “10——0—101”. Note that “−” indicates that no observation was made, that is, no photon passed through the filter.
　ＤａａＳサーバ部１０２は、比較処理で、光子の偏光角度とフィルタ情報が示す角度とを比較する。そうすると、第１，２，６，８，９，１０桁目が互いに合致することがわかる。そこで、ＤａａＳサーバ部１０２は、ステップＳ１０６の処理で、第１，２，６，８，９，１０桁目が合致することを示す桁番号情報をスイッチ５００ａに送信する。 The DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the first, second, sixth, eighth, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the first, second, sixth, eighth, ninth, and tenth digits match in the process of step S106 to the switch 500a.
　そして、ＤａａＳサーバ部１０２は、ステップＳ１０７の処理で、ステップＳ１０１の処理で生成された乱数列において、第１，２，６，８，９，１０桁目のビット値からなるビット値列「１００１０１」をスイッチ５００ａとの共有秘密鍵とする。また、スイッチ５００ａは、観測結果において、ステップＳ１０６の処理でＤａａＳサーバ部１０２から送信された桁番号情報によって示される第１，２，６，８，９，１０桁目のみからなるビット値列「１００１０１」をステップＳ１０８の処理でＤａａＳサーバ部１０２との共有秘密鍵とする。 Then, the DaaS server unit 102, in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “100101” including the bit values of the first, second, sixth, eighth, ninth, and tenth digits. Is a shared secret key with the switch 500a. In addition, the switch 500a, in the observation result, indicates a bit value string “only the first, second, sixth, eighth, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106. 100101 "is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
　また、スイッチ５００ｂがステップＳ１０２の処理で生成した乱数列が「０００１１０１００１」であるとする。ステップＳ１０３の処理で光子が送信されたときのスイッチ５００ｂのフィルタの角度（フィルタ方向情報が示す角度）を、垂直方向を「ａ」、垂直方向に対して１３５°を「ｂ」、水平方向を「ｃ」、および垂直方向に対して４５°を「ｄ」として表す。そうすると、ステップＳ１０２の処理で生成された乱数列に応じたフィルタの角度はそれぞれ、例えば、「ｂｄｄｃａｄａｂｄａ」で表される。そして、ステップＳ１０４の処理におけるスイッチ５００ｂの観測結果は、「―０――１０１―０１」で表される。なお、「－」は、観測しなかった、つまり光子がフィルタを通過しなかったことを表す。 Also, assume that the random number sequence generated by the switch 500b in the process of step S102 is “0001101001”. When the photon is transmitted in the process of step S103, the switch angle of the switch 500b (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”. Then, the angle of the filter according to the random number sequence generated in the process of step S102 is represented by “bddcadabda”, for example. The observation result of the switch 500b in the process of step S104 is represented by “−0−101-01”. Note that “−” indicates that no observation was made, that is, no photon passed through the filter.
　ＤａａＳサーバ部１０２は、比較処理で、光子の偏光角度とフィルタ情報が示す角度とを比較する。そうすると、第２，５，６，７，９，１０桁目が互いに合致することがわかる。そこで、ＤａａＳサーバ部１０２は、ステップＳ１０６の処理で、第２，５，６，７，９，１０桁目が合致することを示す桁番号情報をスイッチ５００ｂに送信する。 The DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the second, fifth, sixth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the second, fifth, sixth, seventh, ninth and tenth digits match to the switch 500b in the process of step S106.
　そして、ＤａａＳサーバ部１０２は、ステップＳ１０７の処理で、ステップＳ１０１の処理で生成された乱数列において、第２，５，６，７，９，１０桁目のビット値からなるビット値列「０１０１０１」をスイッチ５００ｂとの共有秘密鍵とする。また、スイッチ５００ｂは、観測結果において、ステップＳ１０６の処理でＤａａＳサーバ部１０２から送信された桁番号情報によって示される第２，５，６，７，９，１０桁目のみからなるビット値列「０１０１０１」をステップＳ１０８の処理でＤａａＳサーバ部１０２との共有秘密鍵とする。 Then, the DaaS server unit 102, in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “010101” including the bit values of the second, fifth, sixth, seventh, ninth and tenth digits. Is a shared secret key with the switch 500b. In addition, the switch 500b has a bit value string “only the second, fifth, sixth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result. "010101" is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
　また、スイッチ５００ｃがステップＳ１０２の処理で生成した乱数列が「００１１１１１００１」であるとする。ステップＳ１０３の処理で光子が送信されたときのスイッチ５００ｃのフィルタの角度（フィルタ方向情報が示す角度）を、垂直方向を「ａ」、垂直方向に対して１３５°を「ｂ」、水平方向を「ｃ」、および垂直方向に対して４５°を「ｄ」として表す。そうすると、ステップＳ１０２の処理で生成された乱数列に応じたフィルタの角度はそれぞれ、例えば、「ｂｄａｃａａａｂｄａ」で表される。そして、ステップＳ１０４の処理におけるスイッチ５００ｃの観測結果は、「－０１－１－１－０１」で表される。なお、「－」は、観測しなかった、つまり光子がフィルタを通過しなかったことを表す。 Further, it is assumed that the random number sequence generated by the switch 500c in the process of step S102 is “0011111001”. When the photon is transmitted in step S103, the angle of the filter of the switch 500c (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”. Then, the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by “bdacaaaabda”, for example. The observation result of the switch 500c in the process of step S104 is represented by “−01-1-1-01”. Note that “−” indicates that no observation was made, that is, no photon passed through the filter.
　ＤａａＳサーバ部１０２は、比較処理で、光子の偏光角度とフィルタ情報が示す角度とを比較する。そうすると、第２，３，５，７，９，１０桁目が互いに合致することがわかる。そこで、ＤａａＳサーバ部１０２は、ステップＳ１０６の処理で、第２，３，５，７，９，１０桁目が合致することを示す桁番号情報をスイッチ５００ｃに送信する。 The DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the second, third, fifth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the second, third, fifth, seventh, ninth, and tenth digits match to the switch 500c in the process of step S106.
　そして、ＤａａＳサーバ部１０２は、ステップＳ１０７の処理で、ステップＳ１０１の処理で生成された乱数列において、第２，３，５，７，９，１０桁目のビット値からなるビット値列「０１１１０１」をスイッチ５００ｃとの共有秘密鍵とする。また、スイッチ５００ｃは、観測結果において、ステップＳ１０６の処理でＤａａＳサーバ部１０２から送信された桁番号情報によって示される第２，３，５，７，９，１０桁目のみからなるビット値列「０１１１０１」をステップＳ１０８の処理でＤａａＳサーバ部１０２との共有秘密鍵とする。 Then, the DaaS server unit 102, in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “011101” including the bit values of the second, third, fifth, seventh, ninth and tenth digits. Is a shared secret key with the switch 500c. Further, the switch 500c indicates that the bit value string “only the second, third, fifth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result“ “011101” is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
　また、スイッチ５００ｄがステップＳ１０２の処理で生成した乱数列が「１１１１００１００１」であるとする。ステップＳ１０３の処理で光子が送信されたときのスイッチ５００ｄのフィルタの角度（フィルタ方向情報が示す角度）を、垂直方向を「ａ」、垂直方向に対して１３５°を「ｂ」、水平方向を「ｃ」、および垂直方向に対して４５°を「ｄ」として表す。そうすると、ステップＳ１０２の処理で生成された乱数列に応じたフィルタの角度はそれぞれ、例えば、「ａａａｃｂｄａｂｄａ」で表される。そして、ステップＳ１０４の処理におけるスイッチ５００ｄの観測結果は、「１－１－－０１－０１」で表される。なお、「－」は、観測しなかった、つまり光子がフィルタを通過しなかったことを表す。 Further, it is assumed that the random number sequence generated by the switch 500d in the process of step S102 is “1111001001”. When the photon is transmitted in the process of step S103, the switch angle of the switch 500d (the angle indicated by the filter direction information) is “a” for the vertical direction, “b” for 135 ° with respect to the vertical direction, and “b” for the horizontal direction. “C” and 45 ° with respect to the vertical direction are represented as “d”. Then, the angle of the filter corresponding to the random number sequence generated in the process of step S102 is represented by, for example, “aaacbdabda”. The observation result of the switch 500d in the process of step S104 is represented by “1-1-1--01-01”. Note that “−” indicates that no observation was made, that is, no photon passed through the filter.
　ＤａａＳサーバ部１０２は、比較処理で、光子の偏光角度とフィルタ情報が示す角度とを比較する。そうすると、第１，３，６，７，９，１０桁目が互いに合致することがわかる。そこで、ＤａａＳサーバ部１０２は、ステップＳ１０６の処理で、第１，３，６，７，９，１０桁目が合致することを示す桁番号情報をスイッチ５００ｄに送信する。 The DaaS server unit 102 compares the polarization angle of the photon with the angle indicated by the filter information in the comparison process. Then, it can be seen that the first, third, sixth, seventh, ninth and tenth digits match each other. Therefore, the DiaS server unit 102 transmits digit number information indicating that the first, third, sixth, seventh, ninth, and tenth digits match to the switch 500d in the process of step S106.
　そして、ＤａａＳサーバ部１０２は、ステップＳ１０７の処理で、ステップＳ１０１の処理で生成された乱数列において、第１，３，６，７，９，１０桁目のビット値からなるビット値列「１１０１０１」をスイッチ５００ｄとの共有秘密鍵とする。また、スイッチ５００ｄは、観測結果において、ステップＳ１０６の処理でＤａａＳサーバ部１０２から送信された桁番号情報によって示される第１，３，６，７，９，１０桁目のみからなるビット値列「１１０１０１」をステップＳ１０８の処理でＤａａＳサーバ部１０２との共有秘密鍵とする。 Then, the DaaS server unit 102, in the process of step S107, in the random number sequence generated in the process of step S101, the bit value sequence “110101” including the bit values of the first, third, sixth, seventh, ninth and tenth digits. Is a shared secret key with the switch 500d. Further, the switch 500d indicates that the bit value string “only the first, third, sixth, seventh, ninth and tenth digits indicated by the digit number information transmitted from the DaaS server unit 102 in the process of step S106 in the observation result“ 110101 ”is set as a shared secret key with the DaaS server unit 102 in the process of step S108.
　そして、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、各スイッチ５００ａ～ｄとの共有秘密鍵のそれぞれを互いに比較し、合致する桁のビット値からなるビット値列を機密通信システム全体の共有秘密鍵とする（ステップＳ１０９）。 Then, the DaaS server unit 102 compares each of the shared secret keys with the switches 500a to 500d according to an instruction from the administrator unit 101, and shares a bit value string consisting of the bit values of the matching digits for the entire secret communication system. A secret key is set (step S109).
　具体的には、ＤａａＳサーバ部１０２は、ステップＳ１０９の処理で、スイッチ５００ａとの共有秘密鍵「１００１０１」と、スイッチ５００ｂとの共有秘密鍵「０１０１０１」と、スイッチ５００ｃとの共有秘密鍵「０１１１０１」と、スイッチ５００ｄとの共有秘密鍵「１１０１０１」とを各桁ごとに互いに比較して合致しない桁のビット値を消去する。そして、ＤａａＳサーバ部１０２は、残部のビット値によるビット値列を機密通信システム全体の共有秘密鍵とする。具体的には、ＤａａＳサーバ部１０２は、ステップＳ１０９の処理で各共有秘密鍵を各桁ごとに互いに比較すると、第１，２，３桁目のビット値が互いに合致しない。そこで、ＤａａＳサーバ部１０２は、各共有秘密鍵であるビット値列から第１，２，３桁目を消去する。そして、ＤａａＳサーバ部１０２は、残部である第４，５，６桁目のビット値によるビット値列「１０１」を機密通信システム全体の共有秘密鍵とする。 Specifically, in step S109, the DaaS server unit 102 shares the shared secret key “100101” with the switch 500a, the shared secret key “010101” with the switch 500b, and the shared secret key “011101” with the switch 500c. ”And the shared secret key“ 110101 ”with the switch 500d are compared with each other for each digit, and the bit value of the digit that does not match is erased. Then, the DaaS server unit 102 uses the remaining bit value string as the shared secret key of the entire secret communication system. Specifically, when the DaaS server unit 102 compares each shared secret key with each digit in the process of step S109, the bit values of the first, second, and third digits do not match each other. Therefore, the DaaS server unit 102 deletes the first, second, and third digits from the bit value sequence that is each shared secret key. The DaaS server unit 102 uses the remaining bit value string “101” based on the fourth, fifth, and sixth bit values as the shared secret key of the entire secret communication system.
　ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、消去したビット値の桁を示す消去桁情報を各スイッチ５００ａ～ｄに送信する（ステップＳ１１０）。したがって、本例では、消去桁情報は、第１，２，３桁を示す。 The DaAS server unit 102 transmits erase digit information indicating the digit of the erased bit value to each of the switches 500a to 500d in accordance with an instruction from the administrator unit 101 (step S110). Therefore, in this example, the erase digit information indicates the first, second, and third digits.
　スイッチ５００ａ～ｄは、ステップＳ１１０の処理でＤａａＳサーバ部１０２によって送信された消去桁情報に基づいて、ＤａａＳサーバ部１０２との共有秘密鍵の第１，２，３桁目を消去する。そして、スイッチ５００ａ～ｄは、残部である第４，５，６桁目のビット値によるビット値列「１０１」を機密通信システム全体の共有秘密鍵とする（ステップＳ１１１）。 The switches 500a to 500d erase the first, second, and third digits of the shared secret key with the DaaS server unit 102 based on the erased digit information transmitted by the DaaS server unit 102 in the process of step S110. The switches 500a to 500d use the remaining bit value string “101” based on the fourth, fifth, and sixth digit bit values as the shared secret key of the entire secret communication system (step S111).
　本実施形態によれば、情報処理ユニット１００とスイッチ５００ａ～ｄとが、生成した乱数列と受信したビット値列とを比較等することで、少ない手間および低コストで秘密鍵を共有することができる。つまり、少ない手間および低コストで情報処理ユニット１００とスイッチ５００ａ～ｄとに共有秘密鍵を配布することができる。また、本実施形態によれば、量子力学の理論を活用して光子の偏光角度に基づいて秘密鍵を生成するように構成されているので、当該光子の通信路において秘密鍵が漏えいするおそれがない。したがって、情報処理ユニット１００とスイッチ５００ａ～ｄとの間の通信路を高機密化することができる。
実施形態２．
　次に、本発明の第２の実施形態の機密通信システムについて説明する。本実施形態では、情報処理ユニット１００とスイッチ５００ａ～ｚとの間、および各スイッチ５００ａ～ｚの互いの間で、パケットが共有秘密鍵で暗号化されて高機密で送受信される。なお、本実施形態で用いられる共有秘密鍵は、第１の実施形態において生成された機密通信システム全体の共有秘密鍵であることが好ましいが、他の方法で生成された共有秘密鍵であってもよい。 According to this embodiment, the information processing unit 100 and the switches 500a to 500d can share the secret key with less effort and low cost by comparing the generated random number sequence with the received bit value sequence. it can. That is, the shared secret key can be distributed to the information processing unit 100 and the switches 500a to 500d with little effort and low cost. Further, according to the present embodiment, since the secret key is generated based on the polarization angle of the photon using the theory of quantum mechanics, the secret key may be leaked in the communication path of the photon. Absent. Therefore, the communication path between the information processing unit 100 and the switches 500a to 500d can be made highly confidential.
Embodiment 2. FIG.
Next, a secret communication system according to a second embodiment of the present invention will be described. In the present embodiment, packets are encrypted with a shared secret key between the information processing unit 100 and the switches 500a-z and between the switches 500a-z, and are transmitted and received with high confidentiality. The shared secret key used in the present embodiment is preferably the shared secret key of the entire confidential communication system generated in the first embodiment, but is a shared secret key generated by another method. Also good.
　図３は、本発明の第２の実施形態の機密通信システムの構成例を示すブロック図である。図３に示す本発明の第２の実施形態の機密通信システムの構成において、図１に示す本発明の第１の実施形態の機密通信システムと同様な構成要素には、図１と同じ符号を付し、説明を省略する。 FIG. 3 is a block diagram illustrating a configuration example of the confidential communication system according to the second embodiment of this invention. In the configuration of the confidential communication system of the second embodiment of the present invention shown in FIG. 3, the same reference numerals as those in FIG. 1 are given to the same components as those of the confidential communication system of the first embodiment of the present invention shown in FIG. The description is omitted.
　図３に示すように、本発明の第２の実施形態の機密通信システムは、情報処理ユニット１００、およびスイッチ５００ａ～ｚを含む。なお、本実施形態のスイッチ５００ａ～ｚの構成は、第１の実施形態のスイッチ５００ａ～ｄにおける構成と同様であるので説明を省略する。情報処理ユニット１００は、スイッチ５００ａ～ｚと、それぞれ通信回線２００を介して接続されている。スイッチ５００ａ～ｚは、ＬＡＮ／ＷＡＮ３００に接続されている。また、スイッチ５００ａ～ｚには、パケット化された機密情報を互いに送受信するクライアントコンピュータ４００ａ～ｚがそれぞれ接続されている。 As shown in FIG. 3, the confidential communication system according to the second embodiment of the present invention includes an information processing unit 100 and switches 500a-z. Note that the configuration of the switches 500a to 500z of the present embodiment is the same as the configuration of the switches 500a to 500d of the first embodiment, and thus description thereof is omitted. The information processing unit 100 is connected to the switches 500a to 500z via the communication line 200, respectively. The switches 500a to z are connected to the LAN / WAN 300. The switches 500a to 500z are connected to client computers 400a to 400z that transmit / receive packetized confidential information to / from each other.
　次に、本発明の第２の実施形態の機密通信システムの動作について説明する。まず、各スイッチ５００ａ～ｚが互いにパケットを送受信するための準備として、情報処理ユニット１００が、各スイッチ５００ａ～ｚにハッシュ関数の情報を提供する動作について説明する。図４は、情報処理ユニット１００が、各スイッチ５００ａ～ｚにハッシュ関数情報を提供する動作を示すフローチャートである。 Next, the operation of the confidential communication system according to the second embodiment of the present invention will be described. First, an operation in which the information processing unit 100 provides hash function information to each switch 500a-z will be described as preparation for the switches 500a-z to transmit / receive packets to / from each other. FIG. 4 is a flowchart showing an operation in which the information processing unit 100 provides hash function information to each of the switches 500a-z.
　まず、情報処理ユニット１００が、ハッシュ関数表を生成する（ステップＳ２０１）。具体的には、ＤａａＳサーバ部１０２が、アドミニストレータ部１０１の指示に従ってハッシュ関数表を生成する。ハッシュ関数表とは、多数のハッシュ関数とそれらを互いに識別する識別子とがテーブル形式で対応付けられた表である。ハッシュ関数表の生成方法をより具体的に説明すると、ＤａａＳサーバ部１０２は、多数のハッシュ関数が記憶されている記憶手段（図示せず）から、アドミニストレータ部１０１の指示に従って、一のハッシュ関数を読みだす。また、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、乱数を生成する。そして、ＤａａＳサーバ部１０２は、アドミニストレータ部１０１の指示に従って、読みだした一のハッシュ関数と生成した乱数とをテーブル形式で対応付け、ハッシュ関数表とする。なお、ＤａａＳサーバ部１０２によって生成された乱数は、多数のハッシュ関数を互いに識別する識別子としての機能を有する。 First, the information processing unit 100 generates a hash function table (step S201). Specifically, the DaaS server unit 102 generates a hash function table in accordance with instructions from the administrator unit 101. The hash function table is a table in which a large number of hash functions and identifiers for identifying them are associated in a table format. The hash function table generation method will be described more specifically. The DaaS server unit 102 obtains one hash function from a storage unit (not shown) in which a large number of hash functions are stored according to instructions from the administrator unit 101. Read it out. Further, the DaaS server unit 102 generates a random number in accordance with an instruction from the administrator unit 101. Then, in accordance with an instruction from the administrator unit 101, the DaaS server unit 102 associates the read hash function with the generated random number in a table format to form a hash function table. The random number generated by the DaaS server unit 102 has a function as an identifier for identifying a number of hash functions from each other.
　情報処理ユニット１００（より具体的には、ＤａａＳサーバ部１０２）は、ステップＳ２０１の処理で生成したハッシュ関数表を機密通信システム全体の共有秘密鍵のビット値列「１０１」で暗号化して、各スイッチ５００ａ～ｚに送信する（ステップＳ２０２）。各スイッチ５００ａ～ｚは、送信されたハッシュ関数表を機密通信システム全体の共有秘密鍵のビット値列「１０１」で復号し、それぞれの記憶手段（図示せず）に記憶させる。 The information processing unit 100 (more specifically, the DaaS server unit 102) encrypts the hash function table generated in the process of step S201 with the bit value string “101” of the shared secret key of the entire secret communication system, The data is transmitted to the switches 500a to 500z (step S202). Each switch 500a-z decrypts the transmitted hash function table with the bit value string “101” of the shared secret key of the entire secret communication system, and stores it in the respective storage means (not shown).
　次に、各スイッチ５００ａ～ｚがワンタイムパッド共有秘密鍵を生成する動作について説明する。図５は、各スイッチ５００ａ～ｚがワンタイムパッド共有秘密鍵を生成する動作を示すフローチャートである。まず、各スイッチ５００ａ～ｚは、ハッシュ関数表と機密通信システム全体の共有秘密鍵のビット値列「１０１」とに基づいてハッシュ値を算出する（ステップＳ３０１）。具体的には、各スイッチ５００ａ～ｚは、図４に示されたステップＳ２０２の処理で送信されたハッシュ関数表におけるハッシュ関数のそれぞれに、機密通信システム全体の共有秘密鍵のビット値列「１０１」を適用して、ハッシュ値をそれぞれ算出する。 Next, the operation of each switch 500a-z generating a one-time pad shared secret key will be described. FIG. 5 is a flowchart showing an operation in which each switch 500a-z generates a one-time pad shared secret key. First, each of the switches 500a to 500z calculates a hash value based on the hash function table and the bit value string “101” of the shared secret key of the entire secret communication system (step S301). Specifically, each of the switches 500a to 500z includes, in each hash function in the hash function table transmitted in the process of step S202 shown in FIG. To calculate the hash values.
　各スイッチ５００ａ～ｚは、ステップＳ３０１の処理でそれぞれ算出したハッシュ値をワンタイムパッド共有秘密鍵に決定する（ステップＳ３０２）。 Each switch 500a-z determines the hash value calculated in the process of step S301 as the one-time pad shared secret key (step S302).
　次に、機密通信システムにおいて、各スイッチ５００ａ～ｚが互いの間でパケットを送受信する動作について説明する。各スイッチ５００ａ～ｚ間で送受信されるパケットは、例えば、各クライアントコンピュータ４００ａ～ｚ間で送受信されるパケットでもある。 Next, the operation in which each switch 500a-z transmits and receives packets between each other in the confidential communication system will be described. Packets transmitted / received between the switches 500a-z are, for example, packets transmitted / received between the client computers 400a-z.
　図６は、各スイッチ５００ａ～ｚが互いの間でパケットを送受信する動作を示すシーケンス図である。本例では、スイッチ５００ａが、受信したパケットをスイッチ５００ｂに送信する場合について説明するので、図６には、スイッチ５００ａ～ｚのうち、スイッチ５００ａ，ｂのみが示されている。図６に示すように、スイッチ５００ａは、スイッチ５００ｂに送信されたパケットを受信する（ステップＳ４０１）。なお、ステップＳ４０１の処理でスイッチ５００ａが受信したパケットは、例えば、スイッチ５００ａに接続されたクライアントコンピュータ４００ａからスイッチ５００ｂに接続されたクライアントコンピュータ４００ｂ宛に送信されたパケットである。 FIG. 6 is a sequence diagram showing an operation in which each switch 500a-z transmits and receives a packet between each other. In this example, the case where the switch 500a transmits a received packet to the switch 500b will be described. Therefore, only the switches 500a and 500b among the switches 500a to 500z are shown in FIG. As illustrated in FIG. 6, the switch 500a receives the packet transmitted to the switch 500b (step S401). Note that the packet received by the switch 500a in the process of step S401 is, for example, a packet transmitted from the client computer 400a connected to the switch 500a to the client computer 400b connected to the switch 500b.
　スイッチ５００ａは、ステップＳ４０１の処理で受信したパケットの情報を示すパケット情報を通信回線２００を介して情報処理ユニット１００に送信する（ステップＳ４０２）。なお、ステップＳ４０２の処理で送信されるパケット情報は、少なくとも送信元を示す情報、および送信先を示す情報を含む。送信元を示す情報とは、例えば、パケットの送信元の装置のＩＰ（Ｉｎｔｅｒｎｅｔ　Ｐｒｏｔｏｃｏｌ）アドレスやＭＡＣ（Ｍｅｄｉａ　Ａｃｃｅｓｓ　Ｃｏｎｔｒｏｌ）アドレス等である。また、送信先を示す情報とは、例えば、パケットの送信先の装置の電話番号、電子メールアドレス、ＵＲＬ（Ｕｎｉｆｏｒｍ　Ｒｅｓｏｕｒｃｅ　Ｌｏｃａｔｏｒ）等である。 The switch 500a transmits packet information indicating the packet information received in the process of step S401 to the information processing unit 100 via the communication line 200 (step S402). Note that the packet information transmitted in step S402 includes at least information indicating the transmission source and information indicating the transmission destination. The information indicating the transmission source is, for example, an IP (Internet Protocol) address or a MAC (Media Access Control) address of the packet transmission source device. The information indicating the transmission destination is, for example, a telephone number, an e-mail address, a URL (Uniform Resource Locator), or the like of a packet transmission destination device.
　なお、パケット情報には、トポロジ情報とフローエントリ情報とからなる内部転送設定情報が含まれていてもよい。トポロジ情報とは、各スイッチ５００ａ～ｚがＰＦスイッチである場合に、各スイッチ５００ａ～ｚのそれぞれのポートに接続された他のスイッチ等の接続状態を表す情報である。フローエントリ情報は、各スイッチ５００ａ～ｚに記憶されているフローエントリの情報である。 Note that the packet information may include internal transfer setting information including topology information and flow entry information. The topology information is information representing the connection state of other switches connected to the respective ports of the switches 500a to 500z when the switches 500a to 500z are PF switches. The flow entry information is flow entry information stored in each switch 500a-z.
　ステップＳ４０２の処理で送信されたパケット情報を受信した情報処理ユニット１００は、アドレス解決およびネットワーク解決を行う（ステップＳ４０４）。つまり、情報処理ユニット１００は、経路計算を行う。 The information processing unit 100 that has received the packet information transmitted in step S402 performs address resolution and network resolution (step S404). That is, the information processing unit 100 performs route calculation.
　具体的には、情報処理ユニット１００は、例えば、図示しないＤＮＳ（Ｄｏｍａｉｎ　Ｎａｍｅ　Ｓｙｓｔｅｍ）機能部にパケットの送信先を示す情報を提供し、当該パケットの送信先のアドレス（例えば、ＩＰアドレス）を取得する。そして、情報処理ユニット１００は、スイッチ５００ａのＩＰアドレスとパケットの送信先のＩＰアドレスとに基づいて、当該パケットの送信経路を特定する。本例では、当該パケットは、スイッチ５００ａからスイッチ５００ｂに送信されるように送信経路が特定されたとする。 Specifically, the information processing unit 100 provides information indicating a packet transmission destination to a DNS (Domain Name System) function unit (not shown), for example, and obtains an address (for example, an IP address) of the packet transmission destination. To do. Then, the information processing unit 100 specifies the transmission path of the packet based on the IP address of the switch 500a and the IP address of the transmission destination of the packet. In this example, it is assumed that the transmission path is specified so that the packet is transmitted from the switch 500a to the switch 500b.
　なお、アドレス解決およびネットワーク解決の方法は、本例のように、パケットの送信経路が特定されれば、他の方法であってもよい。 Note that the address resolution and network resolution methods may be other methods as long as the packet transmission route is specified as in this example.
　情報処理ユニット１００は、フローテーブルとＭＰＬＳ（Ｍｕｌｔｉ－Ｐｒｏｔｏｃｏｌ　Ｌａｂｅｌ　Ｓｗｉｔｃｈｉｎｇ）ラベルとハッシュ関数表とを対応付けて各スイッチ５００ａ～ｚに送信する（ステップＳ４０４，Ｓ４０５）。なお、ステップＳ４０４，Ｓ４０５の処理で送信されるフローテーブルとは、ステップＳ４０１の処理でスイッチ５００ａが受信したパケットの一連の経路（送信経路）が特定されたテーブルである。また、ＭＰＬＳラベルとは、当該パケットの送信経路に応じたＭＰＬＳラベルである。なお、ＭＰＬＳラベルは、ＤａａＳサーバ部１０２によって生成されてもよいし、専用の装置によって生成されてもよい。ハッシュ関数表とＭＰＬＳラベルおよびフローテーブルとは、例えば乱数が用いられて、それぞれランダムに選択されて対応付けられる。 The information processing unit 100 associates the flow table, the MPLS (Multi-Protocol Label Switching) label, and the hash function table, and transmits them to the switches 500a to 500z (steps S404 and S405). Note that the flow table transmitted in the processing of steps S404 and S405 is a table in which a series of routes (transmission routes) of packets received by the switch 500a in the processing of step S401 are specified. The MPLS label is an MPLS label corresponding to the transmission path of the packet. The MPLS label may be generated by the DaaS server unit 102 or may be generated by a dedicated device. For example, random numbers are used for the hash function table, the MPLS label, and the flow table.
　情報処理ユニット１００（具体的には、例えば、ＤａａＳサーバ部１０２）は、フローテーブルとＭＰＬＳラベルとハッシュ関数表とを対応付けて記憶手段（図示せず）に記憶させる（ステップＳ４０６）。また、スイッチ５００ａ～ｚは、ステップＳ４０４，Ｓ４０５の処理で情報処理ユニット１００が送信したフローテーブルとＭＰＬＳラベルとハッシュ関数表とを対応付けて記憶手段（図示せず）に記憶させる（ステップＳ４０７，Ｓ４０８）。 The information processing unit 100 (specifically, for example, the DaaS server unit 102) stores the flow table, the MPLS label, and the hash function table in association with each other in a storage unit (not shown) (step S406). Further, the switches 500a to 500z store the flow table, the MPLS label, and the hash function table transmitted by the information processing unit 100 in the processes of steps S404 and S405 in association with each other in a storage unit (not shown) (steps S407, S405). S408).
　ステップＳ４０１の処理でパケットを受信したスイッチ５００ａは、ステップＳ４０７の処理で記憶されたハッシュ関数表に含まれるハッシュ関数から、例えば乱数を用いて、ワンタイムパッド共有秘密鍵に使用するハッシュ関数をランダムに選択する。そして、スイッチ５００ａは、選択したハッシュ関数に機密通信システム全体の共有秘密鍵のビット値列「１０１」を適用して、ハッシュ値を算出し、当該パケットを暗号化する（ステップＳ４０９）。 The switch 500a that has received the packet in the process of step S401 randomly selects a hash function to be used for the one-time pad shared secret key using, for example, a random number from the hash functions included in the hash function table stored in the process of step S407. Select Then, the switch 500a applies the bit value string “101” of the shared secret key of the entire secret communication system to the selected hash function, calculates the hash value, and encrypts the packet (step S409).
　さらに、スイッチ５００ａは、ステップＳ４０９の処理で暗号化されたパケットをカプセル化する（ステップＳ４１０）。具体的には、スイッチ５００ａは、ステップＳ４０９の処理で使用したハッシュ関数にハッシュ関数表で対応付けられている識別子と、当該ハッシュ関数表に対応付けられているＭＰＬＳラベルとでカプセル化する。なお、スイッチ５００ａは、ステップＳ４１０の処理で、識別子とＭＰＬＳラベルとが明示されるようにカプセル化する。 Furthermore, the switch 500a encapsulates the packet encrypted in the process of step S409 (step S410). Specifically, the switch 500a encapsulates with the identifier associated with the hash function used in the process of step S409 in the hash function table and the MPLS label associated with the hash function table. Note that the switch 500a encapsulates the identifier and the MPLS label so as to be clearly indicated in the process of step S410.
　そして、スイッチ５００ａは、ステップＳ４１０の処理でカプセル化されたパケットを送信する（ステップＳ４１１）。ステップＳ４１１の処理で送信されたパケットは、カプセル化に用いられたＭＰＬＳラベルのヘッダに基づいてスイッチ５００ａからスイッチ５００ｂに向けて転送されていく。 Then, the switch 500a transmits the packet encapsulated in the process of step S410 (step S411). The packet transmitted in the process of step S411 is transferred from the switch 500a to the switch 500b based on the header of the MPLS label used for encapsulation.
　スイッチ５００ｂは、スイッチ５００ａがステップＳ４１１の処理で送信したパケットを受信すると、受信した当該パケットをワンタイムパッド共有秘密鍵で復号する（ステップＳ４１２）。具体的には、スイッチ５００ｂは、受信したパケットのＭＰＬＳラベルと識別子とに基づいて当該パケットのカプセル化を解除する。そして、スイッチ５００ｂは、記憶手段に記憶されているハッシュ関数表において当該識別子に対応付けられているハッシュ関数に機密通信システム全体の共有秘密鍵のビット値列「１０１」を適用して、ハッシュ値を算出し、当該パケットを復号する。スイッチ５００ｂは、例えば、接続されているクライアントコンピュータ４００ｂに、復号したパケットを送信する。 When the switch 500b receives the packet transmitted by the switch 500a in step S411, the switch 500b decrypts the received packet with the one-time pad shared secret key (step S412). Specifically, the switch 500b releases the encapsulation of the packet based on the MPLS label and the identifier of the received packet. Then, the switch 500b applies the bit value string “101” of the shared secret key of the entire secret communication system to the hash function associated with the identifier in the hash function table stored in the storage unit, and the hash value And the packet is decoded. For example, the switch 500b transmits the decrypted packet to the connected client computer 400b.
　また、スイッチ５００ｂは、ＢＹＥコマンド（セッション終了要求）を情報処理ユニット１００に送信する（ステップＳ４１３）。情報処理ユニット１００（具体的には、例えば、ＤａａＳサーバ部１０２）は、ステップＳ４１３の処理で送信されたセッション終了要求を受信したことに基づいて、以下の処理を行う。すなわち、情報処理ユニット１００は、ステップＳ４０６の処理で記憶手段に記憶させたフローテーブル、ＭＰＬＳラベル、およびハッシュ関数表を当該記憶手段から消去する（ステップＳ４１４）。 In addition, the switch 500b transmits a BYE command (session end request) to the information processing unit 100 (step S413). The information processing unit 100 (specifically, for example, the DaaS server unit 102) performs the following process based on the reception of the session end request transmitted in the process of step S413. That is, the information processing unit 100 deletes the flow table, the MPLS label, and the hash function table stored in the storage unit in the process of step S406 from the storage unit (step S414).
　また、情報処理ユニット１００（具体的には、例えば、ＤａａＳサーバ部１０２）は、ステップＳ４１５，Ｓ４１６として以下の処理を行う。すなわち、情報処理ユニット１００は、スイッチ５００ａ～ｚに、ステップＳ４０７，Ｓ４０８の処理で記憶手段に記憶させたフローテーブル、ＭＰＬＳラベル、およびハッシュ関数表を当該記憶手段から消去する指示を送信する（ステップＳ４１５，Ｓ４１６）。
スイッチ５００ａ～ｚは、ステップＳ４１５，Ｓ４１６の処理で情報処理ユニット１００によって送信された指示に従って、以下の処理を行う。すなわち、スイッチ５００ａ～ｚは、ステップＳ４０７，Ｓ４０８の処理で記憶手段に記憶されたフローテーブル、ＭＰＬＳラベル、およびハッシュ関数表を当該記憶手段から消去する（ステップＳ４１７，Ｓ４１８）。 Further, the information processing unit 100 (specifically, for example, the DaaS server unit 102) performs the following processing as steps S415 and S416. That is, the information processing unit 100 transmits to the switches 500a to 500z an instruction to delete the flow table, the MPLS label, and the hash function table stored in the storage unit in the processing of steps S407 and S408 from the storage unit (step S415, S416).
The switches 500a to 500z perform the following process according to the instruction transmitted by the information processing unit 100 in the processes of steps S415 and S416. In other words, the switches 500a to 500z delete the flow table, MPLS label, and hash function table stored in the storage unit in the processes of steps S407 and S408 from the storage unit (steps S417 and S418).
　本実施形態によれば、機密通信システム全体の共有秘密鍵を用いて当該機密通信システムに含まれる各スイッチ５００ａ～ｚにワンタイムパッド共有秘密鍵を配布することができる。したがって、各スイッチ５００ａ～ｚという多くの情報伝送装置に、機密性が高いワンタイムパッド共有秘密鍵を短時間で配布することが可能になる。 According to the present embodiment, the one-time pad shared secret key can be distributed to each switch 500a-z included in the secret communication system using the secret key of the entire secret communication system. Therefore, it is possible to distribute a highly confidential one-time pad shared secret key in a short time to many information transmission apparatuses such as the switches 500a to 500z.
　また、ＭＰＬＳを使用してワンタイムパッド共有秘密鍵を配布するので、現在の通信事業者の設備と親和性がある。したがって、通信事業者の既存の設備を流用して本発明の実施をすることができるので、通信事業者は、低コストで本発明の実施をすることができる。 Also, since the one-time pad shared secret key is distributed using MPLS, it is compatible with the facilities of the current carrier. Therefore, since the present invention can be implemented by diverting the existing facilities of the telecommunications carrier, the telecommunications carrier can implement the present invention at low cost.
　本実施形態によれば、パケットの送信先のスイッチ５００ｂが当該パケットを受信すると情報処理ユニット１００にセッション終了要求を送信する。そして、情報処理ユニット１００が、セッション終了要求を受信したことに応じて、自ユニットおよび各スイッチ５００ａ～ｚから情報を消去させる。したがって、情報が漏えいするおそれを良好に低減することができる。
実施形態３．
　次に、本発明の第３の実施形態の機密通信システムについて説明する。本実施形態の機密通信システムの構成は、図１に示す第１の実施形態における構成と同様なため、各要素には図１と同じ符号を付し、説明を省略する。図１に示すように、本発明の第３の実施形態の機密通信システムは、通信ネットワーク３００に接続された複数のスイッチ（情報伝送装置）５００ａ～ｄと、各スイッチ５００ａ～ｄとの間をそれぞれ通信回線２００で接続された情報処理ユニット１００とを備える。 According to the present embodiment, when the packet destination switch 500b receives the packet, it transmits a session end request to the information processing unit 100. Then, in response to receiving the session end request, the information processing unit 100 deletes information from the own unit and each of the switches 500a-z. Therefore, it is possible to satisfactorily reduce the risk of information leakage.
Embodiment 3. FIG.
Next, a secret communication system according to a third embodiment of the present invention will be described. Since the configuration of the confidential communication system of the present embodiment is the same as that of the first embodiment shown in FIG. 1, the same reference numerals as those in FIG. As shown in FIG. 1, the confidential communication system according to the third embodiment of the present invention includes a plurality of switches (information transmission apparatuses) 500a to 500d connected to a communication network 300, and each switch 500a to 500d. Each includes an information processing unit 100 connected by a communication line 200.
　情報処理ユニット１００とスイッチ５００ａ～ｄのそれぞれとは、通信回線接続共有秘密鍵をそれぞれ生成する。情報処理ユニット１００は、通信回線接続共有秘密鍵のそれぞれを互いに比較し、自情報処理ユニット１００と各スイッチ５００ａ～ｄとの全体の共有秘密鍵を比較の結果に基づいて生成して、比較の結果を各スイッチ５００ａ～ｄに送信する。 The information processing unit 100 and each of the switches 500a to 500d each generate a communication line connection shared secret key. The information processing unit 100 compares each of the communication line connection shared secret keys with each other, generates the entire shared secret key of the information processing unit 100 and each of the switches 500a to 500d based on the comparison result, and compares The result is transmitted to each switch 500a-d.
　スイッチ５００ａ～ｄのそれぞれは、送信された比較の結果と通信回線接続共有秘密鍵とに基づいて、情報処理ユニット１００と各スイッチ５００ａ～ｄとの全体の全体共有秘密鍵を生成する。 Each of the switches 500a to 500d generates the entire shared secret key of the information processing unit 100 and each of the switches 500a to 500d based on the transmitted comparison result and the communication line connection shared secret key.
　本実施形態によれば、少ない手間および低コストで、通信ネットワーク３００に接続されたスイッチ５００ａ～ｄ間の通信を高機密化することができる。 According to this embodiment, communication between the switches 500a to 500d connected to the communication network 300 can be made highly confidential with less effort and low cost.
　なお、上記の実施形態の一部又は全部は、以下の付記のようにも記載されうるが、以下には限られない。
（付記１）通信ネットワークに接続された複数の情報伝送装置と、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとを備え、前記情報処理ユニットと前記情報伝送装置のそれぞれとは、通信回線接続共有秘密鍵をそれぞれ生成し、前記情報処理ユニットは、前記通信回線接続共有秘密鍵のそれぞれを互いに比較し、当該情報処理ユニットと各情報伝送装置との全体の共有秘密鍵を前記比較の結果に基づいて生成し、前記比較の結果を各情報伝送装置に送信し、前記情報伝送装置のそれぞれは、送信された前記比較の結果と前記通信回線接続共有秘密鍵とに基づいて、前記情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成することを特徴とする機密通信システム。
（付記２）前記情報処理ユニットと前記情報伝送装置のそれぞれとは、量子暗号技術に基づいて、通信回線接続共有秘密鍵をそれぞれ生成する付記１に記載の機密通信システム。
（付記３）前記情報処理ユニットは、前記情報伝送装置のそれぞれに、識別子にそれぞれ対応付けられた複数のハッシュ関数が含まれたハッシュ関数表を配送し、前記各情報伝送装置は互いにパケットを送受信し、パケットの送信側の情報伝送装置は、ハッシュ関数表に含まれた複数のハッシュ関数のうち一のハッシュ関数に前記全体共有秘密鍵を適用したハッシュ値を用いて前記パケットを暗号化し、前記一のハッシュ関数に対応付けられた識別子を明示して、暗号化された前記パケットを送信し、前記各情報伝送装置のうち前記パケットの受信側の情報伝送装置は、前記パケットに明示されている前記識別子に基づいて前記一のハッシュ関数に前記全体共有秘密鍵を適用した前記ハッシュ値を用いて、暗号化された前記パケットを復号することを特徴とする付記１または付記２に記載の機密通信システム。
（付記４）前記情報処理ユニットは、前記各情報伝送装置のそれぞれに、複数のハッシュ関数が含まれたハッシュ関数表を前記全体共有秘密鍵で暗号化して配送し、前記各情報伝送装置のそれぞれは、暗号化されて配送されたハッシュ関数表を前記全体共有秘密鍵で復号する付記３に記載の機密通信システム。
（付記５）前記パケットの受信側の情報伝送装置は、前記パケットを受信するとセッションを終了することを前記情報処理ユニットに要求し、前記情報処理ユニットは、自ユニットに記憶されている前記パケットの送信に応じた情報を消去し、かつ、各情報伝送装置に前記パケットの送信に応じた情報の消去を要求し、前記各情報伝送装置は、情報の消去の要求に応じて、前記パケットの送信に応じた情報を消去することを特徴とする付記３または付記４に記載の機密通信システム。
（付記６）前記情報処理ユニットと前記各情報伝送装置とが互いに接続されている通信回線は光ファイバであることを特徴とする付記１から付記５のうちいずれかに記載の機密通信システム。
（付記７）通信ネットワークに接続された複数の情報伝送装置のそれぞれと、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとが、通信回線接続共有秘密鍵をそれぞれ生成する通信回線接続共有秘密鍵生成ステップと、前記情報処理ユニットが、前記通信回線接続共有秘密鍵生成ステップで生成された前記通信回線接続共有秘密鍵のそれぞれを互いに比較する比較ステップと、前記情報処理ユニットが、前記比較ステップの結果に基づいて、当該情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を前記比較の結果に基づいて生成する全体共有秘密鍵生成ユニット側ステップと、前記情報処理ユニットが、前記比較ステップにおける前記比較の結果を各情報伝送装置に送信する比較結果送信ステップと、前記情報伝送装置のそれぞれが、送信された前記比較の結果と前記通信回線接続共有秘密鍵とに基づいて、前記情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成する全体共有秘密鍵生成装置側ステップとを含むことを特徴とする機密通信システムにおける秘密鍵配送方法。 In addition, although a part or all of said embodiment can be described also as the following additional remarks, it is not restricted to the following.
(Supplementary Note 1) A plurality of information transmission devices connected to a communication network, and information processing units connected to each information transmission device via communication lines, respectively, each of the information processing unit and the information transmission device Each generates a communication line connection shared secret key, and the information processing unit compares each of the communication line connection shared secret keys with each other, and the entire shared secret key between the information processing unit and each information transmission device Is generated based on the result of the comparison, and the result of the comparison is transmitted to each information transmission device. Each of the information transmission devices is based on the transmitted comparison result and the communication line connection shared secret key. A secret communication system characterized by generating an entire shared secret key for the information processing unit and each information transmission device.
(Supplementary note 2) The confidential communication system according to supplementary note 1, wherein each of the information processing unit and the information transmission device generates a communication line connection shared secret key based on a quantum cryptography technique.
(Supplementary Note 3) The information processing unit delivers a hash function table including a plurality of hash functions respectively associated with identifiers to each of the information transmission apparatuses, and the information transmission apparatuses transmit and receive packets to and from each other. The information transmission device on the packet transmission side encrypts the packet using a hash value obtained by applying the entire shared secret key to one hash function among a plurality of hash functions included in the hash function table, An identifier associated with one hash function is clearly specified, and the encrypted packet is transmitted. Among the information transmission apparatuses, the information transmission apparatus on the reception side of the packet is clearly specified in the packet. Based on the identifier, the encrypted packet is decrypted using the hash value obtained by applying the whole shared secret key to the one hash function. Secure communications system according to Appendix 1 or Appendix 2, characterized in that.
(Supplementary Note 4) The information processing unit encrypts and delivers a hash function table including a plurality of hash functions to each of the information transmission apparatuses with the entire shared secret key, and each of the information transmission apparatuses 4. The confidential communication system according to appendix 3, wherein the hash function table encrypted and distributed is decrypted with the entire shared secret key.
(Supplementary Note 5) When receiving the packet, the information transmission apparatus on the packet reception side requests the information processing unit to end the session, and the information processing unit transmits the packet stored in the unit. The information corresponding to the transmission is erased, and each information transmission apparatus is requested to erase the information according to the transmission of the packet, and each information transmission apparatus transmits the packet in response to the information erasure request. The confidential communication system according to supplementary note 3 or supplementary note 4, wherein information according to the above is deleted.
(Supplementary note 6) The confidential communication system according to any one of Supplementary note 1 to Supplementary note 5, wherein a communication line connecting the information processing unit and each of the information transmission apparatuses is an optical fiber.
(Appendix 7) Each of a plurality of information transmission devices connected to a communication network and an information processing unit connected to each information transmission device via a communication line respectively generate a communication line connection shared secret key. A communication line connection shared secret key generation step, a comparison step in which the information processing unit compares each of the communication line connection shared secret keys generated in the communication line connection shared secret key generation step, and the information processing unit. A global shared secret key generation unit side step for generating an overall global shared secret key of the information processing unit and each information transmission device based on the comparison result based on the result of the comparison step; A comparison result transmission step in which the processing unit transmits the result of the comparison in the comparison step to each information transmission device; Each of the information transmission devices generates an overall shared secret key between the information processing unit and each information transmission device based on the transmitted comparison result and the communication line connection shared secret key A secret key distribution method in a secret communication system, comprising: a secret key generation device side step.
　以上、実施形態を参照して本願発明を説明したが、本願発明は上記実施形態に限定されるものではない。本願発明の構成や詳細には、本願発明のスコープ内で当業者が理解し得る様々な変更をすることができる。 The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.
　この出願は、２０１４年２月２７日に出願された日本出願特願２０１４－０３６４７２を基礎とする優先権を主張し、その開示の全てをここに取り込む。 This application claims priority based on Japanese Patent Application No. 2014-036472 filed on February 27, 2014, the entire disclosure of which is incorporated herein.
　１００　　情報処理ユニット
　１０１　　アドミニストレータ部
　１０２　　ＤａａＳサーバ部
　１０３　　単一光子発生部
　２００　　通信回線
　３００　　ＬＡＮ／ＷＡＮ
　４００ａ～ｚ　　クライアントコンピュータ
　５００ａ～ｚ　　スイッチ DESCRIPTION OF SYMBOLS 100 Information processing unit 101 Administrator part 102 DiaS server part 103 Single photon generation part 200 Communication line 300 LAN / WAN
400a-z client computer 500a-z switch

Claims (7)

  1. 　通信ネットワークに接続された複数の情報伝送装置と、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとを備え、
    　前記情報処理ユニットと前記情報伝送装置のそれぞれとは、通信回線接続共有秘密鍵をそれぞれ生成し、
    　前記情報処理ユニットは、
    　前記通信回線接続共有秘密鍵のそれぞれを互いに比較し、
    　当該情報処理ユニットと各情報伝送装置との全体の共有秘密鍵を前記比較の結果に基づいて生成し、
    　前記比較の結果を各情報伝送装置に送信し、
    　前記情報伝送装置のそれぞれは、
    　送信された前記比較の結果と前記通信回線接続共有秘密鍵とに基づいて、前記情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成する
    　ことを特徴とする機密通信システム。     A plurality of information transmission devices connected to a communication network, and an information processing unit connected to each information transmission device by a communication line,
    Each of the information processing unit and the information transmission device generates a communication line connection shared secret key,
    The information processing unit includes:
    Each of the communication line connection shared secret keys is compared with each other,
    An overall shared secret key of the information processing unit and each information transmission device is generated based on the result of the comparison,
    Send the result of the comparison to each information transmission device,
    Each of the information transmission devices
    A secret communication system, characterized in that, based on the transmitted comparison result and the communication line connection shared secret key, an overall shared secret key for the information processing unit and each information transmission apparatus is generated.
  2. 　前記情報処理ユニットと前記情報伝送装置のそれぞれとは、量子暗号技術に基づいて、通信回線接続共有秘密鍵をそれぞれ生成する
    　請求項１に記載の機密通信システム。     The confidential communication system according to claim 1, wherein each of the information processing unit and each of the information transmission apparatuses generates a communication line connection shared secret key based on quantum cryptography.
  3. 　前記情報処理ユニットは、前記情報伝送装置のそれぞれに、識別子にそれぞれ対応付けられた複数のハッシュ関数が含まれたハッシュ関数表を配送し、
    　前記各情報伝送装置は互いにパケットを送受信し、パケットの送信側の情報伝送装置は、ハッシュ関数表に含まれた複数のハッシュ関数のうち一のハッシュ関数に前記全体共有秘密鍵を適用したハッシュ値を用いて前記パケットを暗号化し、前記一のハッシュ関数に対応付けられた識別子を明示して、暗号化された前記パケットを送信し、
    　前記各情報伝送装置のうち前記パケットの受信側の情報伝送装置は、前記パケットに明示されている前記識別子に基づいて前記一のハッシュ関数に前記全体共有秘密鍵を適用した前記ハッシュ値を用いて、暗号化された前記パケットを復号する
    　ことを特徴とする請求項１または請求項２に記載の機密通信システム。     The information processing unit delivers a hash function table including a plurality of hash functions respectively associated with identifiers to each of the information transmission devices,
    Each information transmission apparatus transmits and receives packets to and from each other, and the information transmission apparatus on the packet transmission side applies a hash value obtained by applying the entire shared secret key to one hash function among a plurality of hash functions included in the hash function table. And encrypting the packet using, specifying an identifier associated with the one hash function, and transmitting the encrypted packet,
    Of the information transmission devices, the information transmission device on the reception side of the packet uses the hash value obtained by applying the whole shared secret key to the one hash function based on the identifier specified in the packet. The encrypted communication system according to claim 1 or 2, wherein the encrypted packet is decrypted.
  4. 　前記情報処理ユニットは、前記各情報伝送装置のそれぞれに、複数のハッシュ関数が含まれたハッシュ関数表を前記全体共有秘密鍵で暗号化して配送し、
    　前記各情報伝送装置のそれぞれは、暗号化されて配送されたハッシュ関数表を前記全体共有秘密鍵で復号する
    　請求項３に記載の機密通信システム。     The information processing unit distributes a hash function table including a plurality of hash functions to each of the information transmission devices by encrypting with the entire shared secret key,
    4. The confidential communication system according to claim 3, wherein each of the information transmission apparatuses decrypts the hash function table that has been encrypted and distributed with the entire shared secret key.
  5. 　前記パケットの受信側の情報伝送装置は、前記パケットを受信するとセッションを終了することを前記情報処理ユニットに要求し、
    　前記情報処理ユニットは、自ユニットに記憶されている前記パケットの送信に応じた情報を消去し、かつ、各情報伝送装置に前記パケットの送信に応じた情報の消去を要求し、
    　前記各情報伝送装置は、情報の消去の要求に応じて、前記パケットの送信に応じた情報を消去する
    　ことを特徴とする請求項３または請求項４に記載の機密通信システム。     The information transmission device on the receiving side of the packet requests the information processing unit to end the session when the packet is received,
    The information processing unit deletes information corresponding to the transmission of the packet stored in the unit, and requests each information transmission apparatus to delete information corresponding to the transmission of the packet;
    5. The confidential communication system according to claim 3, wherein each of the information transmission apparatuses erases information according to transmission of the packet in response to a request for erasing information.
  6. 　　前記情報処理ユニットと前記各情報伝送装置とが互いに接続されている通信回線は光ファイバである
    　ことを特徴とする請求項１から請求項５のうちいずれかに記載の機密通信システム。     The confidential communication system according to any one of claims 1 to 5, wherein a communication line in which the information processing unit and each information transmission device are connected to each other is an optical fiber.
  7. 　通信ネットワークに接続された複数の情報伝送装置のそれぞれと、各情報伝送装置との間をそれぞれ通信回線で接続された情報処理ユニットとが、通信回線接続共有秘密鍵をそれぞれ生成し、
    　前記情報処理ユニットが、生成された前記通信回線接続共有秘密鍵のそれぞれを互いに比較し、
    　前記情報処理ユニットが、前記比較結果に基づいて、当該情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を前記比較の結果に基づいて生成し、
    　前記情報処理ユニットが、前記比較の結果を各情報伝送装置に送信し、
    　前記情報伝送装置のそれぞれが、送信された前記比較の結果と前記通信回線接続共有秘密鍵とに基づいて、前記情報処理ユニットと各情報伝送装置との全体の全体共有秘密鍵を生成する
    　ことを特徴とする機密通信システムにおける秘密鍵配送方法。     Each of the plurality of information transmission devices connected to the communication network and the information processing unit connected to each information transmission device by a communication line respectively generate a communication line connection shared secret key,
    The information processing unit compares each of the generated communication line connection shared secret keys with each other,
    The information processing unit generates an entire shared secret key of the information processing unit and each information transmission device based on the comparison result based on the comparison result,
    The information processing unit transmits the result of the comparison to each information transmission device,
    Each of the information transmission devices generates an overall shared secret key of the information processing unit and each of the information transmission devices based on the transmitted comparison result and the communication line connection shared secret key. A secret key distribution method in a secret communication system.
PCT/JP2015/000701 2014-02-27 2015-02-16 Confidential communication system, and method for delivering secret key in confidential communication system WO2015129196A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2014036472 2014-02-27
JP2014-036472 2014-02-27

Publications (1)

Publication Number Publication Date
WO2015129196A1 true WO2015129196A1 (en) 2015-09-03

Family

ID=54008534

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2015/000701 WO2015129196A1 (en) 2014-02-27 2015-02-16 Confidential communication system, and method for delivering secret key in confidential communication system

Country Status (1)

Country Link
WO (1) WO2015129196A1 (en)

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004080663A (en) * 2002-08-22 2004-03-11 Abel Systems Inc Method, apparatus, and program for generating encoding/decoding key, and computer readable recording medium
WO2006003522A1 (en) * 2004-06-29 2006-01-12 Non-Elephant Encryption Systems (Barbados) Inc. A key agreement protocol based on swapping probabilistic adjusting key generation
JP2007053591A (en) * 2005-08-18 2007-03-01 Nec Corp Quantum encryption key distribution system and method
WO2012025987A1 (en) * 2010-08-24 2012-03-01 三菱電機株式会社 Communication terminal, communication system, communication method and communication program

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004080663A (en) * 2002-08-22 2004-03-11 Abel Systems Inc Method, apparatus, and program for generating encoding/decoding key, and computer readable recording medium
WO2006003522A1 (en) * 2004-06-29 2006-01-12 Non-Elephant Encryption Systems (Barbados) Inc. A key agreement protocol based on swapping probabilistic adjusting key generation
JP2007053591A (en) * 2005-08-18 2007-03-01 Nec Corp Quantum encryption key distribution system and method
WO2012025987A1 (en) * 2010-08-24 2012-03-01 三菱電機株式会社 Communication terminal, communication system, communication method and communication program

Similar Documents

Publication Publication Date Title
US11316677B2 (en) Quantum key distribution node apparatus and method for quantum key distribution thereof
JP6641029B2 (en) Key distribution and authentication method and system, and device
EP2401836B1 (en) Pair-wise keying for tunneled virtual private networks technical field
WO2017185999A1 (en) Method, apparatus and system for encryption key distribution and authentication
US10938554B2 (en) Managing private key access in multiple nodes
EP3157225B1 (en) Encrypted ccnx
WO2017114123A1 (en) Key configuration method and key management center, and network element
US20170201382A1 (en) Secure Endpoint Devices
US8566590B2 (en) Encryption information transmitting terminal
US20170126623A1 (en) Protected Subnet Interconnect
EP2638659A1 (en) Method and apparatus to use identify information for digital signing and encrypting content integrity and authenticity in content oriented networks
KR101485279B1 (en) Switch equipment and data processing method for supporting link layer security transmission
CN1938980A (en) Method and apparatus for cryptographically processing data
EP3721579B1 (en) Secure content routing using one-time pads
EP3909196B1 (en) One-time pads encryption hub
KR20170059393A (en) Transparent encryption in a content centric network
Farinacci et al. Locator/ID separation protocol (LISP) data-plane confidentiality
US9832179B2 (en) Stateless server-based encryption associated with a distribution list
WO2016134631A1 (en) Processing method for openflow message, and network element
KR101880999B1 (en) End to end data encrypting system in internet of things network and method of encrypting data using the same
KR101575050B1 (en) Different Units Same Security
JP2005244379A (en) Vpn system, vpn apparatus, and encryption key distribution method used for them
KR101575040B1 (en) Different Units Same Security for instrumentation control
KR101578910B1 (en) Different Units Same Security For Visual Observation System
WO2015129196A1 (en) Confidential communication system, and method for delivering secret key in confidential communication system

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 15754794

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 15754794

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: JP