JP2018174550A - Communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technology capable of improving a degree of freedom of semantics and of simplifying communication.SOLUTION: A communication system 10 connected with a plurality of communication devices, comprises a controller that, in a case where an operation is performed to a group including at least one communication device allocated with an index, controls an authenticated communication device by using a group identifier representing semantics of the group.SELECTED DRAWING: Figure 1

Description

  Embodiments described herein relate generally to a communication system.

  Conventionally, in a communication system having a HAN (Home Area Network) device or the like, a method for associating a group identifier assigned to each packet with a semantic includes a static associating method such as RFC (Request For Comment) 2375. And dynamic association methods such as RFC4566.

RFC 2375 (IPv6 Multicast Address Assignments) RFC 4566 (Session Description Protocol)

  RFC2375 does not require signaling for associating group identifiers with semantics, but the combination of group identifiers and semantics is fixed and limited. In RFC4566, a combination of a group identifier and a semantic is free, but signaling for associating a group identifier with a semantic is necessary, and a correspondence reference is required for each packet. As described above, the method for associating the group identifier with the semantics has advantages and disadvantages between the static association method and the dynamic association method.

  The problem to be solved by the present invention is to provide a communication system capable of improving the degree of freedom of semantics and simplifying communication.

  The communication system according to the embodiment is a communication system connected to a plurality of communication devices, and among the communication devices to which the identifiers of the leaf nodes of the group management tree are respectively assigned, the first communication device and the second communication device And an identifier of a leaf node of the group management tree corresponding to the first communication device and an identifier of the leaf node of the group management tree corresponding to the second communication device Is used as a group identifier of a group for individual communication, and has a control unit that controls an authenticated communication device.

1 is a block diagram showing a configuration of a communication system according to a first embodiment. The figure which shows the connection relation of the controller and apparatus which concern on 1st Embodiment. The figure which shows the correspondence of the node classification which concerns on 1st Embodiment. The block diagram which shows the hardware constitutions of each apparatus which concerns on 1st Embodiment. The block diagram which shows the function structure of the coordinator which concerns on 1st Embodiment. The figure which shows the group management tree and LeafID which concern on 1st Embodiment. The figure which shows the group allocation rule which concerns on 1st Embodiment. The whole sequence which shows the communication procedure which concerns on 1st Embodiment. The authentication sequence which concerns on 1st Embodiment. The key sharing sequence which concerns on 1st Embodiment. The figure which shows the default value of the group communication security policy which concerns on 1st Embodiment. The figure which shows security policy independent TLV contained in the MIH_Net_Group_Manipulate request message which concerns on 1st Embodiment. The figure which shows the security policy independent TLV contained in the MIH_Net_Group_Manipulate response message which concerns on 1st Embodiment. The figure which shows the security policy independent TLV contained in the MIH_MN_Group_Manipulate request message which concerns on 1st Embodiment. The figure which shows the security policy independent TLV contained in the MIH_MN_Group_Manipulate response message which concerns on 1st Embodiment. The figure which shows security policy independent TLV contained in the MIH_Push_Certificate request message which concerns on 1st Embodiment. The figure which shows security policy independent TLV contained in the MIH_Push_Certificate response message which concerns on 1st Embodiment. The figure which shows security policy independent TLV contained in the MIH_Configuration_Update indication message which concerns on 1st Embodiment. The figure which shows security policy independent TLV contained in the MIH_Revoke_Certificate request message which concerns on 1st Embodiment. The figure which shows the security policy independent TLV contained in the MIH_Revoke_Certificate response message which concerns on 1st Embodiment. A detailed sequence of the key sharing phase 1A according to the first embodiment. The detailed sequence of the key sharing phase 1B which concerns on 1st Embodiment. The detailed sequence of the key sharing phase 2 which concerns on 1st Embodiment. The detailed sequence of the key sharing phase 2 which concerns on 1st Embodiment. The detailed sequence of the encryption communication which concerns on 1st Embodiment. The detailed sequence of the certificate revoke which concerns on 1st Embodiment. The detailed sequence of the group key update which concerns on 1st Embodiment.

(First embodiment)
[System Architecture]
FIG. 1 is a block diagram illustrating a configuration example of a communication system according to the first embodiment. In the present embodiment, the security function of the ECHONET Lite node will be described as an example. The ECHONET Lite node supports PANA (Protocol for carrying Authentication for Network Access) defined by IEEE 802.21d and RFC5191 as a security function.

  As illustrated in FIG. 1, the communication system 10 includes a coordinator 20, a controller 30, and a device 40. Among these, one coordinator 20 exists in one ECHONET Lite domain (hereinafter, simply referred to as “domain”). For example, the domain is one HAN (Home Area Network). There is at least one controller 30 in one domain. That is, there are M (M ≧ 1) controllers 30. There is at least one device 40 in one domain. That is, there are N devices 40 (N ≧ 1). FIG. 2 is a diagram illustrating an example of a connection relationship between the controller 30 and the device 40 according to the first embodiment. As shown in FIG. 2, at least one controller 30 and device 40 exist in one domain. The device 40 belongs to a group (application system group) formed by the controller 30. Here, the device 40 may belong to a plurality of application system groups.

  Between the coordinator 20 and each controller 30, procedures of “mutual authentication” and “key sharing” are performed. Similarly, procedures of “mutual authentication” and “key sharing” are performed between the coordinator 20 and each device 40. Further, “encrypted communication” is performed between the controller 30 and the device 40. The encryption key used in the encryption communication is distributed from the coordinator 20 to each controller 30 and each device 40 in the key sharing procedure. The encryption communication may be performed between the controllers 30 or between the devices 40. Detailed procedures of mutual authentication, key sharing, and encryption communication will be described later.

  FIG. 3 is a diagram illustrating a correspondence example of node types according to the first embodiment. In FIG. 3, the correspondence between the ECHONET Lite node type, the PANA node type, and the IEEE 802.21d node type is given as an example. The coordinator 20 is a node that is a main body of group management and security management, and is defined as a new class of ECHONET Lite management and operation-related device groups. The controller 30 and the device 40 are an existing class of ECHONET Lite management and operation-related device groups. The coordinator 20 has the functions of PANA PAA (PANA Authentication Agent) and IEEE 802.21d PoS (Point of Service) with GM (Group Manager). The controller 30 and the device 40 have the functions of PANA PaC (PANA Client) and IEEE 802.21d PoS. The coordinator 20 may not be an ECHONET Lite node device. At this time, the communication system according to the present embodiment is also applicable to systems other than ECHONET Lite.

  FIG. 4 is a block diagram illustrating a hardware configuration example of each device according to the first embodiment. Here, the coordinator 20 will be described as an example. As shown in FIG. 4, the coordinator 20 includes a CPU (Central Processing Unit) 22, a RAM (Random Access Memory) 23, a ROM (Read Only Memory) 24, and a communication I / F 25. The above hardware is connected by a bus 21. The CPU 22 comprehensively controls the operation of the coordinator 20. The CPU 22 controls the overall operation of the coordinator 20 by executing a program stored in the ROM 24 or the like using the RAM 23 as a work area (working area). The communication I / F 25 is an interface for communicating with an external device (for example, the controller 30 or the device 40).

  FIG. 5 is a block diagram illustrating a functional configuration example of the coordinator 20 according to the first embodiment. As shown in FIG. 5, the coordinator 20 includes a control unit 210 and a communication unit 220. The control unit 210 comprehensively controls the operation of the coordinator 20 and executes various processes. Various processes will be described later. The communication unit 220 controls communication with the controller 30 and the device 40. The controller 30 and the device 40 also have a control unit and a communication unit, and execute various processes described later.

[Group Management]
The ECHONET Lite security can handle four types of groups: a HAN group, an individual communication group, an application system group, and a controller group. Among these, the HAN group (number of groups = 1) can be used for encrypted communication between all ECHONET Lite nodes in the domain. In the HAN group, one group encryption key “K1” is shared by all ECHONET Lite nodes in the domain.

  The individual communication group can be used for encrypted communication between two specific ECHONET Lite nodes. If the identifiers of two specific ECHONET Lite nodes are x and y, the group encryption key K_xy or the group encryption key K_yx (in this embodiment, K_xy = K_yx) is shared between the node x and the node y. .

  The application system group (number of groups = M) can be used for encrypted communication between ECHONET Lite nodes (including the controller 30) connected to a specific controller 30. If the identifier of the controller 30 is ctl, the group encryption key K_ctl is shared by the ECHONET Lite nodes connected to the controller ctl.

  The controller group (number of groups = 1) can be used for encrypted communication between all the controllers 30 in the domain. In the controller group, one group encryption key K2 is shared by all the controllers 30 in the domain.

  In the group communication by all the four types of groups described above, it is assumed that encrypted communication according to IEEE 802.21d is performed. Hereinafter, “+” is an operator representing concatenation of character strings, “Type” is a character for identifying any type of LeafID, EUI64 address or short address, “L” (LeafID), “E” (EUI64 address), “ S '(IEEE802.15.4 short address). IDx and IDy are identifiers of two ECHONET Lite nodes belonging to the individual communication group (LeafID, EUI64 address, IEEE802.15.4 short address), IDctl is an identifier of the controller 30 in the application system (LeafID, EUI64 address, IEEE802.15.4 short address).

  At this time, LeafID, EUI64 address, or IEEE802.15.4 short address may be used as IEEE802.21SourceIdentifier assigned to the packet. For example, IEEE 802.21 SourceIdentifier assigned to the packet is “L10”, “E00112233AABBCCDD”, “S0011”, or the like. Leaf ID is an identifier of a leaf node in the IEEE 802.21d group management tree, and can be used as an identifier of the IEEE 802.21d node. The identifier of the leaf node in the group management tree is an example of an index. For example, the index represents an identifier such as a MAC address.

  The LeafID length depends on the group management tree size. In the case of a group management tree with 256 leaf nodes, the LeafID length during BASE16 encoding is 2 bytes. In addition, the EUI64 address length at the time of BASE16 encoding is 16 bytes, and the IEEE 802.15.4 short address length at the time of BASE16 encoding is 4 bytes. Hereinafter, BASE16 encoding is used for encoding LeafID, EUI64 address, and IEEE 802.15.4 short address.

  FIG. 6 is a diagram illustrating an example of the group management tree and LeafID according to the first embodiment. In FIG. 6, LeafID is expressed in binary notation. In the group management tree, a leaf node and each communication node have a one-to-one correspondence. Each node of the group management tree corresponds to a unique 128-bit encryption key. Here, for a certain communication node, a list of encryption keys corresponding to each node existing on the path from the root node to the leaf node is referred to as a device key for the corresponding communication node. For example, for each node existing on the path from the root node to the leaf node, for N0, node 0, node 00, node 000, and node 0000 are obtained. A device key of a certain communication node is shared between the communication node and the GM. For example, if the communication nodes N0, N1, N2, and N3 are group members, the node key used for key encryption is the node key of the node 00. If communication nodes N1, N2, N3, N4, N6, and N7 are group members, the node keys used for key encryption are the node keys of node 00, node 0100, and node 011.

  In group communication, MIHF GroupID defined by IEEE 802.21d is used as IEEE802.21DestinationIdentifier assigned to a packet. The value of MIHF GroupID varies depending on the group. FIG. 7 is a diagram illustrating an example of a group allocation rule according to the first embodiment. For the HAN group, MIHF Broadcast ID (= “”) is used as the MIHF Group ID. For an individual communication group, Type + IDx + '@' + IDy is used as MIHF GroupID. For example, the MIHF GroupID of the individual communication group is “L10 @ 20”, “E00112233AABCCDDD @ 00112233BBCCDDEFF”, “S0011 @ AABB”, and the like.

  For the application system group, Type + '@' + IDctl is used as MIHF GroupID. For example, the MIHF GroupID of the application system group is “L @ 20”, “E @ 00112233BBCCDDEFF”, “S @ AABB”, and the like. For the controller group, “Controllers” is used as the MIHF GroupID. Hereinafter, MIHF GroupID other than MIHF ID and MIHF Broadcast may be referred to as “ID (Type)”. For example, MIHF GroupID “L10 @ 20” is expressed as 10 @ 20 (L).

[Communication procedure]
FIG. 8 is an overall sequence illustrating an example of a communication procedure according to the first embodiment. As shown in FIG. 8, “1. Device registration” and “2. Authentication / key sharing” are performed between the coordinator 20 and the controller 30, and “3. Cryptographic communication” is performed between the controller 30 and the device 40. Is implemented. Similarly, “1. Device registration” and “2. Authentication / key sharing” are performed between the coordinator 20 and the device 40, and “3. Cryptographic communication” is performed between the controller 30 and the device 40. The In “1. device registration” and “2. authentication / key sharing”, the controller 30 and the device 40 can be activated in any order. Hereinafter, the controller 30 and the device 40 may be referred to as “participating nodes”.

  First, device registration is performed between the participating node and the coordinator 20. The participating node discovers the coordinator 20 using UPnP or ECHONET Lite (both without security). The coordinator 20 registers the transmission source when receiving a broadcast such as UPnP or ECHONET Lite. The registration content may be confirmed when authentication / key sharing described later is successful. At this time, if the authentication / key sharing fails, the registered contents are discarded.

  Next, authentication and key sharing are performed between the participating node and the coordinator 20. At the time of authentication between the participating node and the coordinator 20, certificates are exchanged for mutual authentication. If the authentication is successful, the coordinator 20 encrypts the 802.21d device key used for key sharing and distributes it to the participating nodes. In order to reduce the processing load at the time of rebooting, the participating nodes are assumed to hold the information distributed from the coordinator 20 in the nonvolatile memory at the time of authentication and key sharing.

  Key sharing between the participating nodes and the coordinator 20 is performed by distributing a group key from the coordinator 20 to the participating nodes. The group key may be distributed without a request from a participating node (push) or distributed according to a request from a participating node (pull). The coordinator 20 may distribute a certificate regarding another participating node to the participating node.

  Thereafter, encrypted communication is performed between the participating nodes. In addition to the encryption communication between the controller 30 and the device 40, the encryption communication may be performed between the controllers 30 and between the devices. The message used for encrypted communication includes an encrypted ECHONET Lite message, and can be given a digital signature by the source node. In the present embodiment, for example, when multicast is used for message transmission, if the domain range matches the IP link range, the All Nodes link local address (FF02: 0: 0: 0) is used as the multicast address. : 0: 0: 0: 1).

  FIG. 9 is an example of an authentication sequence according to the first embodiment. At the time of authentication, mutual authentication by EAP-TLS defined by RFC5216 using a certificate on PANA is performed. At this time, X. 509 certificate exchange and ECDH (elliptical Diffie-Hellman) key exchange are performed to establish mutual authentication and a session key. From the coordinator 20 to the participating nodes, an X.A. 509 certificates may also be distributed. If the authentication is successful, the coordinator 20 distributes at least the 802.21d device key of the participating node, the 802.21 dLeafID of the coordinator 20, and the 802.21 dLeafID of the participating node to the participating node. It is necessary to encrypt and distribute the 802.21d device key of the participating node. For encryption at this time, an encryption function defined in RFC 6786 is used. The established PANA session may be deleted immediately.

  FIG. 10 is an example of a key sharing sequence according to the first embodiment. The key sharing is divided into a phase (phase 1) performed after the completion of authentication between the participating node and the coordinator 20, and a phase (phase 2) performed when the participating node finds a communication peer that performs cryptographic communication. Phase 1 is divided into phase 1A, which is key sharing between the coordinator 20 and the controller 30, and phase 1B, which is key sharing between the coordinator 20 and the device 40. Note that either phase 1A or phase 1B may be performed first. Phase 2 is divided into phase 2A, which is key sharing between the coordinator 20 and the controller 30, and phase 2B, which is key sharing between the coordinator 20 and the device 40. Note that either phase 2A or phase 2B may be performed first. In each of the phases 1A, 1B, 2A, and 2B, key sharing is performed using IEEE 802.21d. Hereinafter, each phase will be described.

  In phase 1A, the coordinator 20 distributes the individual communication group key between the coordinator 20 and the controller 30 to the controller 30 by push (see (1) in FIG. 10). Then, the coordinator 20 distributes the HAN group key to the controller 30 by pushing (see (2) in FIG. 10). Subsequently, the coordinator 20 distributes the controller group key to the controller 30 by pushing (see (3) in FIG. 10). Thereafter, the coordinator 20 distributes the application system group key to the controller 30 by pushing (see (4) in FIG. 10).

  In phase 1B, the coordinator 20 distributes the group key for individual communication between the coordinator 20 and the device 40 to the device 40 by push (see (5) in FIG. 10). Then, the coordinator 20 distributes the HAN group key to the device 40 by pushing (see (6) in FIG. 10).

  In phase 2A, the coordinator 20 distributes the group key for individual communication between the controller 30 and the device 40 to the controller 30 by pulling or pushing (see (7) in FIG. 10). Here, when phase 2A is performed prior to phase 2B, pull is performed, and when phase 2B is performed prior to phase 2A, push is performed. Then, the coordinator 20 sends the X. 509 certificates are distributed by push (see (8) in FIG. 10).

  In phase 2B, the coordinator 20 distributes the group key for individual communication between the controller 30 and the device 40 to the device 40 by pull or push (see (9) in FIG. 10). Here, when phase 2A is performed prior to phase 2B, pull is performed, and when phase 2B is performed prior to phase 2A, push is performed. Then, the coordinator 20 distributes the application system group key to the device 40 by pushing (see (10) in FIG. 10). Subsequently, the coordinator 20 transmits the X. of the controller 30 to the device 40. 509 certificates are distributed by push (see (11) in FIG. 10).

  In the key sharing sequence shown in FIG. 10, (3) is unnecessary when the controller group key is not used. Also, (4) and (10) are unnecessary when the application system group key is not used. Further, (8) is unnecessary when the transmission source signature of the device 40 is not given in encrypted communication. Further, group key distribution by push can be replaced with group key distribution by pull.

  The IEEE 802.21d message exchanged between the coordinator 20 and the participating node in each step other than (1) and (5) is transmitted to the individual communication group between the coordinator 20 and the participating node. Further, the IEEE 802.21d message exchanged in (1) and (5) is transmitted to the individual node. Each step (1) to (11) shown in FIG. 10 can be classified into three basic procedures: “group key distribution by push”, “group key distribution by pull”, and “certificate distribution by push”. Hereinafter, these three types of procedures will be described.

  At the time of group key distribution by push, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the participating nodes. The participating node that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20.

  At the time of group key distribution by pull, the participating node transmits an MIH_MN_Group_Manipulate request message to the coordinator 20. The coordinator 20 that has received the MIH_MN_Group_Manipulate request message transmits an MIH_MN_Group_Manipulate response message to the participating nodes.

  At the time of certificate distribution by push, the coordinator 20 transmits an MIH_Push_Certificate request message to the participating nodes. The participating node that has received the MIH_Push_Certificate request message transmits an MIH_Push_Certificate response message to the coordinator 20.

  In encryption communication, unicast encryption communication and multicast encryption communication are supported. In unicast encryption communication and multicast encryption communication, an MIH_Configuration_Update indication message including an encrypted ECHONET Lite message is used. The MIH_Configuration_Update indication message of unicast encryption communication is transmitted to the individual communication group. The MIH_Configuration_Update indication message for multicast cryptographic communication is transmitted to a group other than the individual communication group.

  At the time of certificate revocation, the coordinator 20 transmits an MIH_Revoke_Certificate request message by multicast or unicast. When transmitting by multicast, the node (controller 30 or device 40) that has received the MIH_Revoke_Certificate request message within the domain range transmits the MIH_Revoke_Certificate response message to the coordinator 20 by unicast.

  The unicast MIH_Revoke_Certificate request message at the time of certificate revocation is transmitted to the individual communication group between the coordinator 20 and the participating node. The multicast MIH_Revoke_Certificate request message is transmitted to the HAN group. The MIH_Revoke_Certificate response message is transmitted to the individual communication group between the coordinator 20 and the participating node. Certificate revocation by unicast can be used in combination with certificate revocation by multicast.

  At the time of key update, the coordinator 20 activates group key distribution by push. At this time, the MIH_Net_Group_Manipulate request message is broadcasted by multicast or transmitted to individual nodes by unicast. The participating node (controller 30 or device 40) that has received the MIH_Net_Group_Manipulate request message transmits the MIH_Net_Group_Manipulate response message to the coordinator 20 by unicast.

  The unicast MIH_Net_Group_Manipulate request message at the time of key update is transmitted to the individual communication group between the coordinator 20 and the participating node. The multicast MIH_Net_Group_Manipulate request message is transmitted to the HAN group. The MIH_Net_Group_Manipulate response message is transmitted to the individual communication group between the coordinator 20 and the participating node. Unicast key update can be used together with multicast group key update.

  The key update for a certain group is activated when a member leaves the group, when the group is deleted, or when re-registration by a member of the group occurs. In addition, it is preferable to avoid communication interruption due to key update, and the following implementation is recommended for packet transmission and packet reception. In packet transmission, the old key is used for a certain period (T) after the new key is received from the coordinator 20, and thereafter the new key is used. In packet reception, either the old key or the new key can be used for a certain period (2T) after the new key is received from the coordinator 20. Here, “T” is the maximum value of the key update time, for example, the default value is 180 seconds.

  When a node that has not received a new key due to a failure to receive a new key at the time of key update, when receiving a message encrypted with the new key and addressed to the group to which the node belongs, the group key is distributed by pull. Just start. As a result of the key update, if the coordinator 20 does not receive the MIH_Net_Group_Manipulate response message from any of the nodes belonging to the group for a certain period 2T, the key update fails. The coordinator 20 that failed to update the key may attempt to retry the key update, so that a new key may be generated each time the key update is retried.

  When deleting a certain group, a key update specifying an empty Complete Subtree is performed for the group to be deleted. Alternatively, the key update including only one unused leaf node of the group management tree is executed in the Complete Subtree.

[Security]
Of the security common processing applied to all IEEE 802.21d messages used in the present embodiment, a portion of which details are not defined in IEEE 802.21d is defined. There are two types of security for protecting the IEEE 802.21d message: confidentiality and source authentication. Of these, confidentiality is realized by AES-CCM. The source authentication is realized by ECDSA having a key length of 256 bits. When the confidentiality is valid, SAID (Security Association Identifier) TLV (Type Length Value) and Security TLV are used. When the sender authentication is valid, the Signature TLV is used. If both confidentiality and source authentication are valid, SAID TLV, Security TLV, and Signature TLV are used. Hereinafter, a security policy relating to protection of the IEEE 802.21d message and a method for updating a sequence number used in AES-CCM will be described.

  The security policy includes a security policy for individual communication and a security policy for group communication. In the present embodiment, individual communication refers to one-to-one communication using an MIHF ID for the IEEE 802.21d Destination Identifier. The group communication refers to many-to-many communication using MIHF GroupID as the IEEE 802.21d Destination Identifier. As a special case of group communication, communication having two group members is called individual group communication. Individual communication and individual group communication are distinguished from the viewpoint of a security policy.

  For individual communications, confidentiality is always disabled and source authentication is always enabled. Regarding group communication, security policies such as an overall policy, a source-specific policy, and a message-specific policy are defined for each group. The overall policy is a security policy applied to the entire target group. In the overall policy, either “valid” or “invalid” policy is set. The transmission source policy is a security policy applied to each transmission source in the same group. In the transmission source policy, a transmission source to which an exception to the overall policy is applied is specified. For example, the source-specific policy has an exception = “invalid” when the overall policy is “valid” and an exception = “valid” when the overall policy is “invalid”. The policy for each transmission source is specified by a list of transmission source identifiers to which an exception of the entire policy is applied, a Bloom Filter, or a Complete Subtree.

  The message policy is a policy applied to each message in the same group. The message-specific policy specifies a message to which an exception to the overall policy is applied. For example, the message-specific policy has an exception = “invalid” when the overall policy is “valid”, and an exception = “valid” when the overall policy is “invalid”. The message-specific policy is specified by a list of message identifiers, a Bloom Filter, or a bitmap to which an exception of the entire policy is applied.

  FIG. 11 is a diagram illustrating an example of default values of the group communication security policy according to the first embodiment. In FIG. 11, the portions indicated by shading cannot be changed. For example, the security policies that can be changed by the setting are a source-specific policy and a message-specific policy related to source authentication other than the individual communication group. The changeable security policy is set by either setting in advance, embedding policy information in a group identifier, or notifying by a group operation command. The group operation command is MIH_MN_Group_Manipulate or MIH_Net_Group_Manipulate.

  The IEEE 802.21d AES-CCM uses a 13-octet Nonce. This Nonce is a concatenation of Transaction ID (2 octets), Sequence Number (10 octets), and Fragment Number (1 octet). Of these, fields other than SequenceNumber are fields of the packet header. In IEEE 802.21d, a Sequence Number is managed for each group. At the time of authentication and key sharing, “SequenceNumber = 0” is notified to each node. The SequenceNumber is reset to zero at the time of key update, and is notified to each node using a key update procedure.

  When the node is rebooted, the rebooted node performs re-registration with respect to the coordinator 20 by MIH Re-registration (MIH Registration with Request Code = 1) to the coordinator 20 when the Sequence Number used before the reboot is not held. The coordinator 20 performs key update for each group to which the re-registered node belongs. At this time, authentication by PANA and re-authentication are unnecessary. In the present embodiment, since the Sequence Number is 10 octets, it is assumed that the Sequence Number never goes around during the group lifetime. Note that “group alive” means that the number of nodes included in the target group is 1 or more.

[IEEE 802.21d message TLV]
The security policy-independent TLV included in the IEEE 802.21d message used in this embodiment will be described. The security policy-independent TLV is a TLV other than the SAID TLV, the Security TLV, and the Signature TLV in the IEEE 802.21d TLV.

  FIG. 12 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Net_Group_Manipulate request message according to the first embodiment. As shown in FIG. 12, the SourceIdentifier is an identifier of the coordinator 20. In the case of unicast, DestinationIdentifier is an identifier of a participating node or an identifier of an individual communication group between the coordinator 20 and the participating node. The DestinationIdentifier is an identifier of the HAN group in the case of multicast. TargetIdentifier is a group identifier, and LeafID is used in the case of an individual communication group or an application system group.

  ResponseFlag is a response request flag and specifies a value “1”. GroupKeyData is an encrypted group key. When empty CompleteSubtree is specified, GroupKeyData and SAIDNotification are not required. CompleteSubtree is CompleteSubtree data used for decoding GroupKeyData. SequenceNumber is the initial value of the SequenceNumber part of the AES-CCM Nonce field of the transmission packet at the time of encrypted communication. TargetAddress is included in the message in the case of the group for individual communication, and specifies the IP address of the communication peer node for the participating node. SAID Notification designates an SAID corresponding to GroupKeyData.

  FIG. 13 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Net_Group_Manipulate response message according to the first embodiment. As shown in FIG. 13, SourceIdentifier is an identifier of a participating node. DestinationIdentifier is an identifier of the coordinator 20 or a group identifier for individual communication between the coordinator 20 and the participating node. TargetIdentifier is a group identifier, and LeafID is used in the case of an individual communication group or an application system group. GroupStatus is the group operation result, and specifies Join operation successful (value “0”).

  FIG. 14 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_MN_Group_Manipulate request message according to the first embodiment. As shown in FIG. 14, SourceIdentifier is an identifier of a participating node. The DestinationIdentifier is a group identifier for individual communication between the coordinator 20 and the participating node. TargetIdentifier is a group identifier. In the case of an individual communication group, an identifier other than LeafID is designated. GroupAction is a group operation type, and specifies Join the group (value “0”).

  FIG. 15 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_MN_Group_Manipulate response message according to the first embodiment. As shown in FIG. 15, SourceIdentifier is an identifier of the coordinator 20. The DestinationIdentifier is a group identifier for individual communication between the coordinator 20 and the participating node. TargetIdentifier is a group identifier, and LeafID is used in the case of an individual communication group or an application system group. GroupKeyData is an encrypted group key. CompleteSubtree is CompleteSubtree data used for decoding GroupKeyData. SequenceNumber is an initial value of the Sequence Number part of the AES-CCM Nonce field of the transmission packet at the time of encrypted communication. SAID Notification designates an SAID corresponding to GroupKeyData.

  FIG. 16 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Push_Certificate request message according to the first embodiment. As shown in FIG. 16, SourceIdentifier is an identifier of a participating node. The DestinationIdentifier is an identifier of an individual communication group between the coordinator 20 and the participating node in the case of unicast. The DestinationIdentifier is an identifier of the HAN group in the case of multicast. Certificate is a communication peer node that performs cryptographic communication with a participating node. 509 certificate.

  FIG. 17 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Push_Certificate response message according to the first embodiment. As shown in FIG. 17, SourceIdentifier is an identifier of the coordinator 20. DestinationIdentifier is an identifier of an individual communication group between the coordinator 20 and the participating node. CertificateSerialNumber is an X.distributed by the HIM_Push_Certificate request message. 509 is the serial number of the certificate. Certificate Status is the status of the distributed certificate, and if the certificate is valid, Certificate Valid (value “0”) is entered.

  FIG. 18 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Configuration_Update indication message according to the first embodiment. As shown in FIG. 18, SourceIdentifier is an identifier of a transmission source node. DestinationIdentifier is a destination identifier. In the case of unicast encryption communication, the identifier of the individual communication group is used. Here, the identifier of the individual communication group is IDx + '@' + IDy (L) or IDy + '@' + IDx (L). In addition, in the case of multicast encrypted communication, the DestinationIdentifier uses the application system group identifier ('@' + IDctl (L)) when using the application system group, and the HAN group identifier ("") when using other groups. Is done. The ConfigurationData includes an ECHONET Lite message.

  FIG. 19 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Revoke_Certificate request message according to the first embodiment. As shown in FIG. 19, the SourceIdentifier is an identifier of the coordinator 20. The DestinationIdentifier is an identifier of an individual communication group between the coordinator 20 and the participating node in the case of unicast. The DestinationIdentifier is an identifier of the HAN group in the case of multicast. CertificateSerialNumber is the serial number of the revoked certificate. CertificateRevocation is the digital signature of the issuer of the revoked certificate.

  FIG. 20 is a diagram illustrating an example of a security policy-independent TLV included in the MIH_Revoke_Certificate response message according to the first embodiment. As shown in FIG. 20, SourceIdentifier is an identifier of a participating node. DestinationIdentifier is an identifier of an individual communication group between the coordinator 20 and the participating node. CertificateSerialNumber is the serial number of the revoked certificate. Certificate Status is the status of the certificate to be revoked. If the revocation is successful, Certificate Valid (value “1”) is set.

  Next, a detailed sequence for key sharing, cryptographic communication, certificate revocation, and key update according to the present embodiment will be described.

[Detailed sequence of key sharing phase 1]
FIG. 21 is an example of a detailed sequence of the key sharing phase 1A according to the first embodiment. In FIG. 21, IDctl represents the identifier of the controller 30, IDcdn represents the identifier of the coordinator 20, and IDdev represents the identifier of the device 40. Further, (1) to (4) shown in FIG. 21 correspond to (1) to (4) shown in FIG.

  As shown in (1) of FIG. 21, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30. In the MIH_Net_Group_Manipulate request message, “src = IDcdn (L), dst = IDctl (L), GroupKeyData (K_cdn, ctlIdNidLidID = IDNIDLIDID = IdCidID, IDNidID” included. In addition, the controller 30 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDcdn (L), TargetID = IDdev @ IDcdn (L), GroupStatus, Signature”.

  As shown in (2) of FIG. 21, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {GroupKeyDataNoKet}, CompleteSubget, ResponseID”. It is. The controller 30 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message. The MIH_Net_Group_Manipulate response message includes “src = IDctl (L), dst = IDctl @ IDcdn (L), SAID, Security {TargetID =“ ”, GroupStatus}”.

  As shown in (3) of FIG. 21, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30. In the MIH_Net_Group_Manipulate request message, “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {GroupKeyDataTitleIDN”, CompleteSubrate, ResponseID ” included. The controller 30 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDctl (L), dst = IDctl @ IDcdn (L), SAID, Security {TargetID =“ Controllers ”, GroupStatus}”.

  As shown in (4) of FIG. 21, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30. In the MIH_Net_Group_Manipulate request message, “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {GroupKeyDataStiFidIDLlIDID, GroupIDFlID, IDIdNl, IDIdNl, IDIdNl, IDIdNl, IDIdlL Is included. The controller 30 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDctl (L), dst = IDctl @ IDcdn (L), SAID, Security {TargetID = @ IDctl (L), GroupStatus}”.

  Note that in the key sharing phase 1A, prior to (1) in FIG. 21, MIH registration defined by IEEE 802.21-2008 may be performed from the controller 30 to the coordinator 20.

  FIG. 22 is an example of a detailed sequence of the key sharing phase 1B according to the first embodiment. In FIG. 22, IDctl represents the identifier of the controller 30, IDcdn represents the identifier of the coordinator 20, and IDdev represents the identifier of the device 40. Further, (5) and (6) shown in FIG. 22 correspond to (5) and (6) shown in FIG.

  As shown in (5) of FIG. 22, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the device 40. In the MIH_Net_Group_Manimate request message, “src = IDcdn (L), dst = IDdev (L), GroupKeyData (K_cdn, dev), CompleteSubtree, ResponseIDcNidIDNidID = IDNIDIDIDID included. The device 40 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDcdn (L), TargetID = IDdev @ IDcdn (L), GroupStatus, Signature”.

  As shown in (6) of FIG. 22, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the device 40. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {GroupKeyData (K1), CompleteSubsure, ResponseID, NoIDS”. It is. The device 40 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {TargetID =“ ”, GroupStatus}”.

  In the key sharing phase 1B, prior to (5) in FIG. 22, MIH registration defined by IEEE 802.21-2008 may be performed from the device 40 to the coordinator 20.

[Detailed sequence of key sharing phase 2]
FIG. 23 is an example of a detailed sequence of the key sharing phase 2 according to the first embodiment. In FIG. 23, a case where Phase 2A precedes Phase 2B is taken as an example. In FIG. 23, IDctl represents the identifier of the controller 30, IDcdn represents the identifier of the coordinator 20, and IDdev represents the identifier of the device 40. Further, (7) to (11) shown in FIG. 23 correspond to (7) to (11) shown in FIG.

  As shown in (7) of FIG. 23, the controller 30 transmits an MIH_MN_Group_Manipulate request message to the coordinator 20. The MIH_MN_Group_Manipulate request message includes “src = IDctl (L), dst = IDctl @ IDcdn (L), SAID, Security {TargetID = IDdev @ IDctl (E or S), GroupAction}”. The coordinator 20 that has received the MIH_MN_Group_Manipulate request message transmits an MIH_MN_Group_Manipulate response message to the controller 30. The MIH_MN_Group_Manipulate response message includes: “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {GroupKeyData (N_ctl, devIDLIDID, ID, ID, ID) } "Is included.

  As shown in (8) of FIG. 23, the coordinator 20 transmits an MIH_Push_Certificate request message to the controller 30. The MIH_Push_Certificate request message includes “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {Certificate (CERTdev)}”. The controller 30 that has received the MIH_Push_Certificate request message transmits an MIH_Push_Certificate response message to the coordinator 20. The MIH_Push_Certificate response message includes “src = IDctl (L), dst = IDctl @ IDcdn (L), SAID, Security {CertificateSerialNumber, CertificateStatus}}.

  As shown in (9) of FIG. 23, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the device 40. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {GroupKeyDataId (K_cttlDetID = TlIdID = TlIdID = Id, IDtdn ID = L), SAIDNotif, SequenceNum} ”. The device 40 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {TargetID = IDdev @ IDctl (L), GroupStatus}”.

  As shown in (10) of FIG. 23, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the device 40. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {GroupKeyData (K_ctl), CompleteSubID, IDID = IDID, ID = IDT, ID = IDT, ID = DtID, IDT} Is included. The device 40 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {TargetID = @ IDctl (L), GroupStatus}”.

  As illustrated in (11) of FIG. 23, the coordinator 20 transmits an MIH_Push_Certificate request message to the device 40. The MIH_Push_Certificate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {Certificate (CERctctl)}”. The device 40 that has received the MIH_Push_Certificate request message transmits an MIH_Push_Certificate response message to the coordinator 20. The MIH_Push_Certificate response message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {CertificateSerialNumber, CertificateStatus}”.

  When the key sharing phase 2B is used for key sharing for communication between the controllers 30, the device 40 (IDdev) in the key sharing phase 2B communicates with the controller 30 (IDctl ′) of the communication partner of the controller 30 (IDctl) in the key sharing phase 2A. ) And (7) is omitted. When the key sharing phase 2A is used for key sharing for inter-device communication, the controller 30 (IDctl) in the key sharing phase 2A communicates with the device 40 (IDdev ′) of the communication partner of the device 40 (IDdev) in the key sharing phase 2B. And (7) is omitted.

  FIG. 24 is an example of a detailed sequence of the key sharing phase 2 according to the first embodiment. In FIG. 24, a case where Phase 2B precedes Phase 2A is taken as an example. In FIG. 24, IDctl represents the identifier of the controller 30, IDcdn represents the identifier of the coordinator 20, and IDdev represents the identifier of the device 40. Further, (7) to (11) shown in FIG. 24 correspond to (7) to (11) shown in FIG.

  As illustrated in (9) of FIG. 24, the device 40 transmits an MIH_MN_Group_Manipulate request message to the coordinator 20. The MIH_MN_Group_Manipulate request message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {TargetID = IDdev @ IDctl (E or S), GroupAction}”. The coordinator 20 that has received the MIH_MN_Group_Manipulate request message transmits an MIH_MN_Group_Manipulate response message to the device 40. The MIH_MN_Group_Manipulate response message includes "src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {GroupKeyData (K_ctl, devID, ID, ID, ID, ID, ID) } "Is included.

  As shown in (10) of FIG. 24, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the device 40. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {GroupKeyData (K_ctl), CompleteSubID, IDID = IDID, ID = IDT, ID = IDT, ID = DtID, IDT} Is included. The device 40 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDdev (L), dst = IDdev @ IDcdn (L), SAID, Security {TargetID = @ IDctl (L), GroupStatus}”.

  As shown in (11) of FIG. 24, the coordinator 20 transmits an MIH_Push_Certificate request message to the device 40. The MIH_Push_Certificate request message includes “src = IDcdn (L), dst = IDdev @ IDcdn (L), SAID, Security {Certificate (CERctctl)}”. The device 40 that has received the MIH_Push_Certificate request message transmits an MIH_Push_Certificate response message to the coordinator 20. The MIH_Push_Certificate response message includes “src = IDdev (L), dst = IDcdn (L), SAID, Security {CertificateSerialNumber, CertificateStatus}”.

  As shown in (7) of FIG. 24, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30. The MIH_Net_Group_Manipulate request message includes “src = IDcdn (L), dst = IDctl @ IDcdn (L), SAID, Security {GroupKeyDataId (K_ctlDtIdId = TlIdID = TlIdID, IDttlID = Id, L), SAIDNotif, SequenceNum} ”. The controller 30 that has received the MIH_Net_Group_Manipulate request message transmits an MIH_Net_Group_Manipulate response message to the coordinator 20. The MIH_Net_Group_Manipulate response message includes “src = IDctl (L), dst = IDctl @ cdn (L), SAID, Security {TargetID = IDdev @ IDctl (L), GroupStatus}”.

  As shown in (8) of FIG. 24, the coordinator 20 transmits an MIH_Push_Certificate request message to the controller 30. The MIH_Push_Certificate request message includes “src = IDcdn (L), dst = IDctl (L), SAID, Security {Certificate (CERTdev)}”. The controller 30 that has received the MIH_Push_Certificate request message transmits an MIH_Push_Certificate response message to the coordinator 20. The MIH_Push_Certificate response message includes “src = IDclt (L), dst = IDcdn (L), SAID, Security {CertificateSerialNumber, CertificateStatus}”.

[Detailed sequence of encrypted communication]
FIG. 25 is an example of a detailed sequence of cryptographic communication according to the first embodiment. As illustrated in FIG. 25, the controller 30 or the device 40 transmits and receives an MIH_Configuration_Update indication message to the controller 30 or the device 40 in unicast encryption communication and multicast encryption communication. The MIH_Configuration_Update indication message is transmitted / received by the controller 30 or the device 40 (IDx) and the controller 30 or the device 40 (IDy).

[Detailed sequence of certificate revocation]
FIG. 26 is an example of a detailed sequence of certificate revocation according to the first embodiment. As shown in FIG. 26, the coordinator 20 transmits an MIH_Revoke_Certificate request message to the controller 30 or the device 40 by multicast or unicast. As a result, the controller 30 or the device 40 transmits an MIH_Revoke_Certificate response message to the coordinator 20.

[Detailed sequence of group key update]
FIG. 27 is an example of a detailed sequence of group key update according to the first embodiment. As shown in FIG. 27, the coordinator 20 transmits an MIH_Net_Group_Manipulate request message to the controller 30 or the device 40 by multicast or unicast. As a result, the controller 30 or the device 40 transmits an MIH_Net_Group_Manipulate response message to the coordinator 20.

  According to the present embodiment, a group identifier is transmitted and received in a group including a variable value field that represents the group semantic in the structure of the group identifier, and the value of which is unchanged during the lifetime of the group. Communication can be simplified while improving.

  Information including processing procedures, control procedures, specific names, various data, parameters, and the like shown in the document and drawings can be arbitrarily changed unless otherwise specified. Each component of the illustrated control apparatus is functionally conceptual and does not necessarily need to be physically configured as illustrated. In other words, the specific form of distribution or integration of each device is not limited to the illustrated one, and all or a part thereof is functionally or physically distributed or arbitrarily distributed in arbitrary units according to various burdens or usage conditions. Can be integrated.

  In addition, the coordinator 20, the controller 30, and the device 40 included in the communication system 10 according to the above-described embodiment can be realized by using a general-purpose computer device as basic hardware, for example. The program to be executed has a module configuration including each function described above. The program can be installed in an installable or executable format and recorded on a computer-readable recording medium such as a CD-ROM, CD-R, or DVD, or provided in advance in a ROM or the like. May be.

  Further, the above-described embodiments are presented as examples, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the scope of the invention. Moreover, each embodiment can be combined suitably as long as the contents do not contradict each other. Each embodiment and its modifications are included in the scope and gist of the invention, and are included in the invention described in the claims and the equivalents thereof.

10 Communication System 20 Coordinator 30 Controller 40 Equipment

Claims (10)

A communication system connected to a plurality of communication devices,
When an operation is performed on an individual communication group composed of a first communication device and a second communication device among communication devices each assigned an identifier of a leaf node of a group management tree, the first A character string including the identifier of the leaf node of the group management tree corresponding to one communication device and the identifier of the leaf node of the group management tree corresponding to the second communication device is used as the group identifier of the group for the individual communication, A control unit for controlling the authenticated communication device,
The group identifier has a different format depending on the type of group,
Communications system.   The communication system according to claim 1, wherein the control unit performs control using the group identifier including a variable value field whose value is unchanged during the lifetime of the group to be operated.   The communication system according to claim 1, wherein the control unit performs control by using the group identifier that is different for each group when there are a plurality of groups.   The communication system according to claim 2, wherein the control unit performs control using the group identifier including the variable value field including an identifier of a representative communication device among communication devices existing in the group.   The communication system according to any one of claims 1 to 4, wherein the control unit encrypts a packet including the group identifier using a group common key that is different for each group.   The communication system according to claim 5, wherein the control unit distributes the group common key using IEEE 802.21d.   The control unit notifies an identifier of a leaf node of the group management tree corresponding to the other communication device of the individual communication group in response to a request from one communication device of the individual communication group. The communication system according to 1.   The communication system according to claim 1, wherein the control unit distributes an identifier and a device key of a leaf node corresponding to the communication device when the communication device is initially connected.   The communication system according to any one of claims 1 to 8, wherein the control unit performs control using the group identifier including information representing a security policy.   The group identifier of the group for individual communication corresponds to information indicating a type of group identifier, an identifier of a leaf node of a group management tree corresponding to the first communication device, a predetermined symbol, and the second communication device. The communication system according to any one of claims 1 to 9, wherein the identifier of the leaf node of the group management tree to be displayed is expressed in a format connected by an operator representing connection of character strings.

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