JP2022055738A - Communication system, master station device, slave station device, and computer program - Google Patents

Abstract

To reduce VLAN setting work.SOLUTION: There is provided a communication system comprising a master station device and slave station devices connected to the master station device via a VLAN. The master station device includes a storage unit for storing, for each slave station device, a VLAN ID for identifying the VLAN which the slave station device belongs to, and a first control unit for creating a specific control frame for controlling the slave station device, the specific control frame including a VLAN tag in which the VLAN ID is stored. The slave station devices include a second control unit for processing the specific control frame and creating a response frame, the second control unit referring to a destination address and Ethertype, irrespective of information of the VLAN tag in a received frame, and thereby assessing whether the received frame is the specific control frame.SELECTED DRAWING: Figure 1

Description

The present disclosure relates to communication systems, master station devices, slave station devices, and computer programs.

VLAN (Virtual Local Area Network) is defined in IEEE 802.1Q (Non-Patent Document 1). In a VLAN, one network is logically divided into a plurality of network segments. The VLAN ID of each communication device belonging to the VLAN is registered in advance, and the frame is transferred to the communication device belonging to the VLAN specified by the VLAN ID in the frame.

IEEE Standard for Local and metropolitan area networks --Virtual Bridged Local Area Networks, (US), IEEE, May 2006

When one master station device and a large number of slave station devices are connected by a VLAN and the master station device controls each slave station device via the VLAN, in the slave station device, the VLAN ID of the VLAN to which the slave station device belongs is It was registered. However, there is a problem that the work of setting the VLAN ID for each of a large number of slave station devices is complicated and costs a lot.

The communication system according to one aspect of the present disclosure is a communication system including a master station device and a slave station device connected to the master station device via a VLAN, and the master station device is the slave station. Each device includes a storage unit that stores a VLAN ID for identifying the VLAN to which the slave station device belongs, and a first control unit that creates a specific control frame for controlling the slave station device. The specific control frame includes a VLAN tag in which the VLAN ID is stored, the slave station device includes a second control unit that processes the specific control frame and creates a response frame, and the second control unit includes a second control unit. Regardless of the information of the VLAN tag in the receiving frame, it is determined whether or not the receiving frame is the specific control frame by referring to the destination address and the ether type.

The master station device according to one aspect of the present disclosure is a master station device connected to a slave station device via a VLAN, and is a VLAN for identifying the VLAN to which the slave station device belongs for each slave station device. The specific control frame includes a storage unit for storing an ID and a control unit for creating a specific control frame for controlling the slave station device, and the specific control frame includes a VLAN tag in which the VLAN ID is stored, and the specific control frame is included. The VLAN ID is not set in the slave station device before the control frame is transmitted to the slave station device.

The slave station device according to one aspect of the present disclosure is a slave station device connected to the master station device via a VLAN, and processes a specific control frame transmitted from the master station device to create a response frame. The specific control frame includes a VLAN tag containing a VLAN ID for identifying the VLAN to which the slave station device belongs, and the control unit includes the VLAN tag information in the receiving frame regardless of the information of the VLAN tag. By referring to the destination address and the ether type, it is determined whether or not the received frame is the specific control frame.

The computer program according to one aspect of the present disclosure is a computer program for operating a computer as a slave station device connected to a master station device via a VLAN, and is a specific specification transmitted to the computer from the master station device. A step of processing a control frame and creating a response frame is executed, and the received frame refers to the destination address and the ether type regardless of the information of the VLAN tag in the received frame, so that the received frame is the specific control frame. Includes determining whether or not.

The present disclosure can be realized not only as a master station apparatus having the above-mentioned characteristic configuration, but also as a method in which characteristic processing in the master station apparatus is a step, or a computer as a master station apparatus. It can be realized as a functioning computer program. Further, the present disclosure can be realized not only as a slave station device having the above-mentioned characteristic configuration, but also as a method in which characteristic processing in the slave station device is a step, or a computer as a slave station. It can be realized as a computer program that functions as a device. In the present disclosure, a part or all of a master station device is realized as a semiconductor integrated circuit, a part or all of a slave station device is realized as a semiconductor integrated circuit, and a communication system including a master station device and a slave station device is included. Can be realized as.

According to the present disclosure, it is not necessary to set the VLAN information in the slave station device.

It is a figure which shows an example of the structure of the communication system which concerns on embodiment. It is a block diagram which shows an example of the internal structure of a master station apparatus. It is a block diagram which shows an example of the hardware composition of the control part of a master station apparatus. It is a figure which shows an example of the structure of the specific control frame which is an Information OAM frame. It is a figure which shows an example of a VLAN list. It is a figure which shows an example of the structure of the specific control frame which is the Organization Specific OAM frame. It is a block diagram which shows an example of the internal structure of a slave station apparatus. It is a block diagram which shows an example of the hardware composition of the control part of a slave station apparatus. It is a flowchart which shows an example of the operation procedure in the master station apparatus which concerns on embodiment. It is a flowchart which shows an example of the operation procedure in the slave station apparatus which concerns on embodiment. It is a figure which shows an example of the structure of the specific control frame which is an Ethernet VSM frame.

<Summary of Embodiments of the present disclosure>
Hereinafter, the outlines of the embodiments of the present disclosure will be described in a list.

(1) The communication system according to the present embodiment is a communication system including a master station device and a slave station device connected to the master station device via a VLAN, and the master station device is the child. Each station device includes a storage unit that stores a VLAN ID for identifying the VLAN to which the slave station device belongs, and a first control unit that creates a specific control frame for controlling the slave station device. The specific control frame includes a VLAN tag in which the VLAN ID is stored, the slave station device includes a second control unit that processes the specific control frame and creates a response frame, and the second control unit includes the second control unit. , Regardless of the information of the VLAN tag in the received frame, it is determined whether or not the received frame is the specific control frame by referring to the destination address and the ether type. Since the VLAN tag is not used to identify the specific control frame in the slave station device, it is not necessary to set the VLAN information in the slave station device. Therefore, it is possible to reduce the work of setting the VLAN.

(2) The specific control frame may include a multicast destination address reserved for Ethernet OAM (“Ethernet” is a registered trademark. OAM: Operations, Administration, Maintenance) as a destination address. When transmitting a control frame by unicast, the address of the slave station device must be managed by the master station device. A frame having a multicast destination address reserved for Link OAM cannot pass through a VLAN network because it is specified in Non-Patent Document 1 to be discarded by an L2 switch (Layer 2 switch). Therefore, such a frame cannot be used as a specific control frame. By using the multicast destination address reserved for Ethernet OAM without such a disposal rule, it is not necessary to manage the address of the slave station device in the master station device, and the work of setting the VLAN can be further reduced. ..

(3) The specific control frame may include an ether type specified in Link OAM or an Ethernet type specified in Ethernet OAM. As a result, the slave station device is based on whether or not the ether type (0x8809) specified in the Link OAM or the ether type (0x8902) specified in the Ethernet OAM is stored in the type field of the received frame. , Specific control frame can be identified.

(4) The specific control frame includes an OAM subtype as a subtype of the ether type, and the second control unit further refers to the subtype so that the reception frame is the specific control frame. It may be determined whether or not there is. By using the OAM subtype (0x03) for the identification of the specific control frame in the slave station device, more accurate identification of the specific control frame becomes possible.

(5) The second control unit may determine whether or not the specific control frame is a genuine specific control frame based on the vendor code included in the specific control frame. As a result, an illegal specific control frame can be identified in the slave station device, and it is possible to prevent the slave station device from being illegally set.

(6) The specific control frame includes a field in which certificate information for proving a genuine specific control frame is stored, and the second control unit includes information stored in the field included in the specific control frame. Further, it may be determined whether or not the specific control frame is a genuine specific control frame. As a result, it is possible to more accurately identify an illegal specific control frame in the slave station device.

(7) The second control unit may create the response frame including the source address of the specific control frame as the destination address and the same VLAN tag as the VLAN tag of the specific control frame. Even if the VLAN ID is not set in advance in the slave station device, the slave station device can create a response frame and transmit the response frame from the slave station device to the master station device.

(8) When the VLAN ID of the slave station device for which a session has been established with the master station device is changed, the first control unit keeps the session state and stores the changed VLAN ID. A specific control frame containing a tag may be created. In the present disclosure, a specific control frame is identified without using a VLAN ID in the slave station device. Therefore, even if the VLAN ID is changed, it is not necessary to change the session state with the master station device in the slave station device. With the above configuration, when the VLAN ID assigned to the slave station device changes, it is not necessary to perform a new communication process (handshake) between the master station device and the slave station device to establish a session. ..

(9) The slave station device further includes a storage unit, and when the second control unit receives the specific control frame transmitted from the master station device, the VLAN included in the received specific control frame. When the ID is stored in the storage unit and the second control unit creates a control frame to be transmitted from the slave station device to the master station device, the VLAN ID stored in the storage unit is stored in the VLAN. You may create a control frame containing tags. As a result, even if the operator does not set the VLAN ID in the slave station device, the slave station device can create a control frame including the VLAN tag and transmit the control frame from the slave station device to the master station device.

(10) The specific control frame may be a Link OAM frame or an Ethernet OAM frame. As a result, the master station device can control the slave station device by using the Link OAM frame or the Ethernet OAM frame without setting the VLAN information in the slave station device.

(11) The master station device according to the present embodiment is a master station device connected to the slave station device via a VLAN, and for each of the slave station devices, a VLAN to which the slave station device belongs is identified. The specific control frame includes a storage unit for storing a VLAN ID and a control unit for creating a specific control frame for controlling the slave station device, and the specific control frame includes a VLAN tag in which the VLAN ID is stored. The VLAN ID is not set in the slave station device before the specific control frame is transmitted to the slave station device. Since the VLAN information is not set in the slave station device, it is possible to reduce the work of setting the VLAN.

(12) The slave station device according to the present embodiment is a slave station device connected to the master station device via a VLAN, and processes a specific control frame transmitted from the master station device to create a response frame. The specific control frame includes a VLAN tag in which a VLAN ID for identifying the VLAN to which the slave station device belongs is stored, and the control unit includes the information of the VLAN tag in the receiving frame. , The destination address and the ether type are used to determine whether or not the received frame is the specific control frame. Since the VLAN tag is not used to identify the specific control frame in the slave station device, it is not necessary to set the VLAN information in the slave station device. Therefore, it is possible to reduce the work of setting the VLAN.

(13) The computer program according to the present embodiment is a computer program for operating a computer as a slave station device connected to a master station device via a VLAN, and is transmitted to the computer from the master station device. The receiving frame is controlled by the specific control frame by processing the specific control frame and executing a step of creating a response frame, and the step refers to the destination address and the ether type regardless of the information of the VLAN tag in the receiving frame. Includes determining whether or not it is a frame. Since the VLAN tag is not used to identify the specific control frame in the slave station device, it is not necessary to set the VLAN information in the slave station device. Therefore, it is possible to reduce the work of setting the VLAN.

<Details of Embodiments of the present disclosure>
Hereinafter, the details of the embodiment of the present invention will be described with reference to the drawings. In addition, at least a part of the embodiments described below may be arbitrarily combined.

In this embodiment, a communication system that communicates by Link OAM will be described.

[1. Communication system configuration]
FIG. 1 is a diagram showing an example of a configuration of a communication system according to the present embodiment. As shown in FIG. 1, the communication system 10 includes a master station device 1, a slave station device 2, a network 3, and a management server 7.

The network 3 includes the same number of VLANs as the slave station device 2. The slave station device 2 and the VLAN have a one-to-one correspondence. Each VLAN has a different VLAN ID from each other. That is, a unique VLAN ID is assigned to each of the slave station devices 2. In the present embodiment, the VLAN ID assigned to the own device is not set in the slave station device 2. The network 3 includes at least one L2 switch 4.

The network 3 includes a communication cable such as an optical fiber or a coaxial cable. A wireless communication transmission line can be adopted instead of the communication line.
The master station device 1 located on the upper side of the communication system 10 is communicably connected to the upper network 5, and the slave station device 2 located on the lower side of the communication system 10 is communicably connected to the lower network 6. There is. The lower network 6 is composed of, for example, a home LAN (Local Area Network) or an in-house LAN.

The master station device 1 and the slave station device 2 are communication devices that can transmit and receive communication data that are PDUs (Protocol Data Units) such as Ethernet (registered trademark) frames and IP packets, and are compatible with Ethernet OAM. Further, the master station device 1 and the slave station device 2 have the function of Link OAM specified in IEEE802.3ah.
Link OAM is an OAM function and a control protocol that is premised on use in P2P (Point to Point) for the purpose of monitoring physical lines and communication status between opposing Ethernet devices.

The master station device 1 is connected to the management server 7. The management server 7 can transmit various commands to the master station device 1.

[2. Internal configuration of master station device]
FIG. 2 is a block diagram showing an example of the internal configuration of the master station device 1. As shown in FIG. 2, the master station apparatus 1 of the present embodiment has an upper interface unit 11, a control unit (first control unit) 12, a first processing unit 13, a second processing unit 14, and a lower interface unit 15. , Uplink buffer 16, downlink buffer 17, storage unit 18, and external interface unit 19.

The upper interface unit 11 includes an integrated circuit that executes communication processing of layer 1 and layer 2 with respect to electrical signals in the upstream direction and the downstream direction.
The control unit 12, the first processing unit 13, and the second processing unit 14 execute an integrated circuit (integrated circuit) that executes communication processing in accordance with a predetermined communication standard such as IEEE 802.3ah for the communication data in the uplink direction and the downlink direction. For example, it consists of a MAC chip).

FIG. 3 is a block diagram showing an example of the hardware configuration of the control unit 12. In a specific example, the control unit 12 inputs a processor 12a, a non-volatile memory 12b composed of a ROM (Read Only Memory), a volatile memory 12c composed of a RAM (Random Access Memory), and communication data and a control signal. It has an input / output unit 12d for outputting. The processor 12a includes, for example, a CPU (Central Processing Unit).

The master station program 12e is stored in the non-volatile memory 12b. The master station apparatus 1 is configured to include a computer, and the function of the master station apparatus 1 is exhibited by executing the master station program 12e, which is a computer program stored in the storage device of the computer, by the processor 12a. .. The master station program 12e can be stored in a recording medium such as a CD-ROM or a flash memory. The master station program 12e can be distributed by a recording medium or a communication means and downloaded to the non-volatile memory 12b via the input / output unit 12d. The processor 12a can execute the master station program 12e. When the processor 12a executes the master station program 12e, the master station apparatus 1 can execute a process as described later.

The configuration of the control unit 12 is not limited to the above. The control unit 12 may be, for example, an ASIC (Application Specific Integrated Circuit) or a programmable logic device such as a gate array or FPGA (Field Programmable Gate Array). In this case, the ASIC or the programmable logic device is configured to be able to execute the same processing as the master station program 12e.

See FIG. 2 again. The first processing unit 13 and the second processing unit 14 consist of logic circuit devices designed to enable specific information processing, and include, for example, at least one of an ASIC and a programmable logic device.

The lower interface unit 15 includes a communication device including an element for transmitting and receiving an electric signal or an optical signal.
The lower interface unit 15 converts the signal received from the network 3 into communication data (frame) composed of electric signals, and outputs the converted communication data to the first processing unit 13. If there is communication data in the downlink buffer 17, the lower interface unit 15 converts the communication data into an electric signal or an optical signal, and sends the converted signal to the network 3.

The first processing unit 13 has the functions of the VLAN determination unit 13a and the control frame determination unit 13b.

The VLAN determination unit 13a determines whether or not the communication data includes a VLAN tag regardless of whether the received communication data (received frame) is a user frame or a control frame. Further, when the receiving frame includes a VLAN tag, the VLAN determination unit 13a determines whether or not the receiving frame is communication data to be transferred. The storage unit 18 stores a VLAN table in which a VLAN ID to be transferred is registered. The VLAN determination unit 13a refers to the VLAN table and determines whether or not the received frame should be transferred. When the received frame is communication data to be transferred, the communication data is given to the control frame determination unit 13b. If the received frame is not the communication data to be transferred, the communication data is discarded.

The control frame determination unit 13b determines whether or not the reception frame given by the VLAN determination unit 13a is a control frame. The control frame includes each communication frame of Link OAM, LACP, and Ethernet OAM. In particular, the Link OAM control frame includes an Information OAM control frame and an Organization Specific OAM control frame. In the present embodiment, the control frame of Link OAM is a specific control frame defined as described later. The control frame determination unit 13b indicates whether the input communication data is a control frame including a specific control frame (for example, a control frame by LACP is included in addition to the specific control frame), or a PDU other than the control frame (for example, a PDU other than the control frame). Protocol Data Unit).

When the input communication data is determined to be a control frame, the first processing unit 13 outputs the control frame to the control unit 12. When it is determined that the input communication data is not a control frame, the first processing unit 13 outputs the communication data to the uplink buffer 16.

The upper interface unit 11 converts the transmission signal received from the upper network 5 into communication data, and outputs the converted communication data to the second processing unit 14.
If there is communication data in the uplink buffer 16, the upper interface unit 11 converts the communication data into a transmission signal and sends the converted transmission signal to the upper network 5.

The second processing unit 14 has the functions of the VLAN determination unit 14a and the merging unit 14b.

The VLAN determination unit 14a determines whether or not the received communication data includes a VLAN tag. Further, when the received data includes a VLAN tag, the VLAN determination unit 14a refers to the VLAN table of the storage unit 18 and determines whether or not the received data should be transferred. If the received data is communication data to be transferred, the communication data is given to the merging unit 14b. If the received data is not the communication data to be transferred, the communication data is discarded.

The control unit 12 creates a specific control frame as described later, and outputs the specific control frame to the second processing unit 14. The output specific control frame is given to the merging unit 14b. The control unit 12 can also create a control frame other than the specific control frame (for example, a control frame by LACP) and output it to the merging unit 14b. The merging unit 14b outputs a control frame (including a specific control frame) given by the control unit 12. Further, the merging unit 14b outputs the communication data given by the VLAN determination unit 14a. The communication data (including the control frame) output from the merging unit 14b is written in the downlink buffer 17.

The external interface unit 19 is connected to the management server 7 via a communication line. The external interface unit 19 can receive the command transmitted from the management server 7. The external interface unit 19 is connected to the control unit 12. The command received by the external interface unit 19 from the management server 7 is given to the control unit 12.

The control unit 12 creates a specific control frame for controlling the slave station device. The specific control frame is a Link OAM frame. More specifically, the specific control frame is an Information OAM frame or an Organization Specific OAM frame. The Information OAM frame is a kind of Link OAM frame, and the Organization Specific OAM frame is also a kind of Link OAM frame.

FIG. 4 is a diagram showing an example of the configuration of a specific control frame which is an Information OAM frame. The Information OAM frame has fields such as a destination address 101, a source address 102, a length / type 104, a subtype 105, a flag 106, and data. Since the use of VLAN is not assumed in Link OAM, a general Information OAM frame does not include a VLAN tag. However, the Information OAM frame as the specific control frame according to the present embodiment has a field of the VLAN tag 103 between the source address 102 and the length / type 104. In the example of FIG. 4, the two-stage VLAN tag field is provided, but it may be one-stage. However, since the VLAN ID that can be specified by the one-stage VLAN tag is 0-4095, the number of VLAN IDs used is limited to 4096 or less.

The destination address 101 stores the multicast destination address of the Ethernet OAM. The multicast destination address reserved for Ethernet OAM is 01-80-C2-00-00-3x (x is a hexadecimal number between 0 and F). The frame in which the multicast destination address (01-80-C2-00-00-02) reserved for Link OAM is stored in the destination address 101 is discarded by the L2 switch 4 (see FIG. 1). On the other hand, the frame in which the multicast destination address of the Ethernet OAM is stored in the destination address 101 is forwarded by the L2 switch 4. Therefore, the specific control frame can be transmitted to the target slave station device.

The MAC address of the master station device 1 is stored in the source address 102.

The VLAN ID is stored in the VLAN tag 103. As described above, each slave station device 2 is assigned a unique VLAN ID. The control unit 12 stores the VLAN ID assigned to the target slave station device 2 in the VLAN tag 103 of the specific control frame.

The VLAN list 18a is stored in the storage unit 18. The VLAN list 18a is used to identify the VLAN ID assigned to the target slave station device 2. FIG. 5 is a diagram showing an example of a VLAN list. In the example shown in FIG. 5, the number of the slave station device 2 and the two-stage VLAN ID are associated with each other. That is, in this example, a dual VLAN ID including the VLAN ID 1 and the VLAN ID 2 is defined. For example, when the control unit 12 transmits a specific control frame to the slave station device 2 of # 1, the control unit 12 refers to the VLAN list 18a and sets 1 and 101 as the VLAN ID 1 and the VLAN ID 2 corresponding to the slave station device number # 1, respectively. Identify. Similarly, when the control unit 12 transmits the specific control frame to the slave station device 2 of # 2, the control unit 12 refers to the VLAN list 18a and sets 1 and 102 as the VLAN ID 1 and the VLAN ID 2 corresponding to the slave station device number # 2. Identify each. The control unit 12 stores the specified VLAN IDs (VLAN ID1 and VLAN ID2) in the VLAN tag 103 of the specific control frame.

See FIG. 4 again. Length / type 104 is a field that specifies the ether type. The length / type 104 stores the ether type "0x8809" specified in the Link OAM.

The subtype 105 stores a subtype value "0x03" indicating OAM.

There are two states in a Link OAM session. One state is a state in which the session is disconnected (hereinafter referred to as "session disconnected state"), and the other state is a state in which the session is established (hereinafter referred to as "session established state"). The flag 106 stores a value indicating the state of the session between the master station device 1 and the slave station device 2. For example, if the sessions of both devices have not been established, "40" is stored in the flag 106. If the session of the transmitting device (in this case, the master station device 1) is established and the session of the opposite device (in this case, the slave station device 2) is not established, "72" is stored in the flag 106. If a session of both devices is established, "80" is stored in the flag 106.

The data fields of the Information OAM frame include the Local Information TLV field, the Remote Information TLV field, and the Information TLV # 3 field. The Local Information TLV field includes each field of OUI (Organizationally Unique Identifier) 107 and Vendor Specific Info 108.

The vendor-specific identification number is stored in the UI 107. The Vendor Specific Info 108 stores arbitrary information defined by the vendor. In this embodiment, encrypted certificate information is stored in Vendor Specific Info 108.

FIG. 6 is a diagram showing an example of the configuration of a specific control frame which is an Organization Specific OAM frame. The Organization Specific OAM frame has fields such as destination address 201, source address 202, length / type 204, subtype 205, flag 206, and data. Like the Information OAM frame, the general Organization Specific OAM frame does not contain a VLAN tag. However, the Organization Specific OAM ram as the specific control frame according to this embodiment has a field of VLAN tag 203 between the source address 202 and the length / type 204.

The values stored in the destination address 201, source address 202, VLAN tag 203, length / type 204, subtype 205, and flag 206 fields are the same as in the Information OAM frame, so the description thereof will be omitted.

The data field of the Organization Specific OAM frame includes a plurality of fields such as OUI207. The vendor-specific identification number is stored in the UI 207.

The specific control frame as described above is sent from the lower interface unit 15 to the network 3 (see FIG. 2). In the L2 switch 4 (see FIG. 1) included in the network 3, the VLAN ID and the number of the port connected to the slave station device 2 to which the VLAN ID is assigned are stored in association with each other. The L2 switch 4 identifies a port corresponding to the VLAN ID stored in the VLAN tags 103 and 203 included in the specific control frame, and outputs the specific control frame from the port. The specific control frame is received by the slave station device 2 connected to the port, that is, the slave station device 2 corresponding to the VLAN ID. With the above configuration, it is not necessary to manage the MAC address of the slave station device 2 in the master station device 1, and the setting work related to the VLAN is reduced.

[3. Internal configuration of slave station device]
FIG. 7 is a block diagram showing an example of the internal configuration of the slave station device 2. As shown in FIG. 7, the slave station device 2 of the present embodiment has a lower interface unit 21, a control unit (second control unit) 22, a first processing unit 23, a second processing unit 24, and an upper interface unit 25. , Upstream buffer 26, downlink buffer 27, and storage unit 28.

The lower interface unit 21 includes an integrated circuit that executes communication processing of layer 1 and layer 2 with respect to electrical signals in the upstream direction and the downstream direction.
The control unit 22, the first processing unit 23, and the second processing unit 24 are integrated circuits that execute communication processing in accordance with a predetermined communication standard such as IEEE 802.3ah for the communication data in the uplink direction and the downlink direction (the integrated circuit). For example, it consists of a MAC chip).

FIG. 8 is a block diagram showing an example of the hardware configuration of the control unit 22. In a specific example, the control unit 22 includes a processor 22a, a non-volatile memory 22b composed of a ROM, a volatile memory 22c composed of a RAM, and an input / output unit 22d for inputting / outputting communication data and control signals. .. The processor 22a includes, for example, a CPU (Central Processing Unit).

The slave station program 22e is stored in the non-volatile memory 22b. The slave station device 2 is configured to include a computer, and the function of the slave station device 2 is exhibited by executing the slave station program 22e, which is a computer program stored in the storage device of the computer, by the processor 22a. .. The slave station program 22e can be stored in a recording medium such as a CD-ROM or a flash memory. The slave station program 22e can be distributed by a recording medium or a communication means and downloaded to the non-volatile memory 22b via the input / output unit 22d. The processor 22a can execute the slave station program 22e. When the processor 22a executes the slave station program 22e, the slave station device 2 can execute a process as described later.

The configuration of the control unit 22 is not limited to the above. The control unit 22 may be, for example, an ASIC or a programmable logic device such as a gate array or FPGA. In this case, the ASIC or the programmable logic device is configured to be able to execute the same processing as the slave station program 22e.

See FIG. 7 again. The first processing unit 23 and the second processing unit 24 consist of logic circuit devices designed to enable specific information processing, and include, for example, at least one of an ASIC and a programmable logic device.

The upper interface unit 25 includes a communication device including an element for transmitting and receiving an electric signal or an optical signal.
The upper interface unit 25 converts the signal received from the network 3 into communication data (frame) composed of electric signals, and outputs the converted communication data to the first processing unit 23. If there is communication data in the uplink buffer 26, the upper interface unit 25 converts the communication data into an electric signal or an optical signal, and sends the converted signal to the network 3.

The first processing unit 23 has the functions of the control frame determination unit 23a and the VLAN determination unit 23b.

The control frame determination unit 23a determines whether or not the received communication data (received frame) is a control frame including a specific control frame. Specifically, the control frame determination unit 23a controls whether the input communication data is a control frame of Link OAM (specific control frame) or a control frame by a control protocol other than Link OAM (for example, LACP). Determine if it is a PDU other than the frame.

When the input communication data is determined to be a control frame, the first processing unit 23 outputs the control frame to the control unit 22. When it is determined that the input communication data is not a control frame, the communication data is given to the VLAN determination unit 23b.

The VLAN determination unit 23b determines whether or not the given communication data includes a VLAN tag. Further, when the receiving frame includes a VLAN tag, the VLAN determination unit 23b determines whether or not the receiving frame is communication data to be transferred. The storage unit 28 stores a VLAN table in which a VLAN ID to be transferred is registered. The VLAN determination unit 23b refers to the VLAN table and determines whether or not the received frame should be transferred. If the received frame is communication data to be transferred, the communication data is output to the downlink buffer 27. If the received frame is not the communication data to be transferred, the communication data is discarded.

The lower interface unit 21 converts the transmission signal received from the lower network 6 into communication data, and outputs the converted communication data to the second processing unit 24.
If there is communication data in the downlink buffer 27, the lower interface unit 21 converts the communication data into a transmission signal and sends the converted transmission signal to the lower network 6.

The second processing unit 24 has the functions of the VLAN determination unit 24a and the merging unit 24b.

The VLAN determination unit 24a determines whether or not the received communication data includes a VLAN tag. Further, when the received data includes a VLAN tag, the VLAN determination unit 24a refers to the VLAN table of the storage unit 28 and determines whether or not the received data should be transferred. When the received data is communication data to be transferred, the communication data is given to the merging unit 24b. If the received data is not the communication data to be transferred, the communication data is discarded.

When the specific control frame is received, the control unit 22 processes the specific control frame, creates a response frame as described later, and outputs the response frame to the second processing unit 24. The output response frame is given to the confluence portion 24b. The merging unit 24b outputs a specific control frame given by the control unit 22. Further, the merging unit 24b outputs the communication data given by the VLAN determination unit 24a. The communication data (including the specific control frame) output from the merging unit 24b is written in the uplink buffer 26.

The storage unit 28 stores the VLAN ID stored in the VLAN tags 103 and 203 included in the most recently received specific control frame. That is, when the slave station device 2 receives the specific control frame, the VLAN ID of the storage unit 28 is overwritten with the VLAN ID included in the received specific control frame. This VLAN ID is a VLAN ID assigned to the slave station device 2. That is, the storage unit 28 stores the VLAN ID assigned to the own device.

In the slave station device 2, information about the VLAN of the specific control frame other than the VLAN ID of the own device is not stored in advance. When the slave station device 2 receives the specific control frame from the master station device 1, the slave station device 2 learns (stores) the VLAN ID assigned to the own device. Therefore, the work of setting the VLAN is reduced.

The storage unit 28 stores the MAC address stored in the source addresses 102 and 202 included in the most recently received specific control frame, that is, the MAC address of the master station device 1. The MAC address stored in the storage unit 28 is used to create a response frame.

The control unit 22 determines whether or not the received frame is a specific control frame by referring to the destination address and the ether type regardless of the information of the VLAN tag in the received frame. In this determination, the control unit 22 does not refer to the VLAN tag in the given receive frame. The control unit 22 refers to the destination address and the value of the length / type field in the given received frame, the destination address is the multicast destination address of the Ethernet OAM, and the value of the length / type is specified in the Link OAM. If it is an Ethernet type "0x8809", it is determined that it is a specific control frame. Subtype values may be used to identify the particular control frame in the slave station device 2. That is, if the destination address is the multicast destination address of Ethernet OAM, the length / type value is "0x8809", and the subtype is the value "0x03" indicating OAM, the control unit 22 receives. It can be determined that the frame is a specific control frame.

When the control unit 22 receives the specific control frame, the control unit 22 creates a response frame. The type of response frame is the same as that of the specific control frame. If the specific control frame is an Information OAM frame, a response frame that is an Information OAM frame is created. If the specific control frame is an Organization Specific OAM frame, a response frame that is an Organization Specific OAM frame is created. The response frame includes a VLAN tag as in the specific control frame.

See FIGS. 4 and 6. The MAC addresses of the master station device 1 stored in the storage unit 28 are stored in the destination addresses 101 and 201 of the response frame. That is, the response frame is transmitted unicast. The MAC address of the own device (slave station device 2) is stored in the source addresses 102 and 202 of the response frame.

The VLAN tags 103 and 203 of the response frame store the same VLAN ID as the VLAN ID stored in the VLAN tags 103 and 203 of the specific control frame. That is, the VLAN IDs assigned to the own device are stored in the VLAN tags 103 and 203 of the response frame. Further, the response frame lengths / types 104, 204 and subtypes 105, 205 also store the same values as the specific control frame lengths / types 104, 204 and subtypes 105, 205. That is, the response frame lengths / types 104 and 204 store the ether type "0x8809" specified in Link OAM, and the subtypes 105 and 205 store the value "0x03" indicating OAM.

The control unit 22 stores a value indicating the state of the session at that time in the fields of the flags 106 and 206 of the response frame. For example, if the sessions of both devices have not been established, "40" is stored in flags 106 and 206. If the session of the transmitting device (in this case, the slave station device 2) is established and the session of the opposite device (in this case, the master station device 1) is not established, "72" is stored in the flags 106 and 206. To. If a session of both devices is established, "80" is stored in flags 106 and 206.

When the response frame is an Information OAM frame, the same value as the specific control frame is stored in each of the OUI 107 and the Vendor Specific Info 108. That is, the vendor-specific identification number is stored in the UI 107, and the encrypted certificate information is stored in the Vendor Specific Info 108 (see FIG. 4). The Vendor Specific Info 108 in the response frame may have a different value from the Vendor Specific Info in the specific control frame. For example, the Vendor Specific Info 108 in the response frame may store information for proving that the device is a legitimate slave station device.

When the response frame is an Organization Specific OAM frame, the same value as the specific control frame is stored in the OUI 207. That is, the vendor-specific identification number is stored in the UI 207 (see FIG. 6).

The response frame as described above is sent from the upper interface unit 25 to the network 3 (see FIG. 7). The response frame is transmitted to the master station device 1 having the MAC address specified as the destination address via the network 3.

Further, the control unit 22 can create a control frame (a control frame emitted from the slave station device 2, a general control frame different from the specific control frame) that is not a response frame. In this case, the control unit 22 uses the MAC address of the master station device 1 stored in the storage unit 28 and the VLAN ID assigned to the own device. Specifically, the control unit 22 stores the MAC address of the master station device 1 in the destination addresses 101 and 201 of the control frame which is the Link OAM frame, and stores the MAC address of the own device 2 in the source addresses 102 and 202. (See FIGS. 4 and 6). Further, the control unit 22 adds the VLAN tags 103 and 203 between the source addresses 102 and 202 and the length / type 104 and 204, and stores the VLAN ID assigned to the own device in the VLAN tags 103 and 203. .. The control unit 22 stores the ether type "0x8809" specified in Link OAM in the length / type 104 and 204 of the control frame, and stores the value "0x03" indicating OAM in the subtypes 105 and 205. .. The control unit 22 stores a value indicating the state of the session at that time in the fields of the flags 106 and 206 of the control frame.

When the control frame is an Information OAM frame, the OUI 107 stores the vendor-specific identification number, and the Vendor Specific Info 108 stores the encrypted certificate information (see FIG. 4). When the control frame is an Organization Specific OAM frame, the vendor-specific identification number is stored in the OUI 207 (see FIG. 6).

[4. Operation of communication system]
The operation of the communication system 10 according to the present embodiment will be described below. FIG. 9 is a flowchart showing an example of the operation procedure in the master station apparatus according to the present embodiment, and FIG. 10 is a flowchart showing an example of the operation procedure in the slave station apparatus according to the present embodiment. The following operations of the master station apparatus are realized by the processor 12a executing the master station program 12e, and the operations of the slave station apparatus are realized by the processor 22a executing the slave station program 22e.

See FIG. The transmission of the specific control frame is executed periodically. The master station device 1 manages a transmission timer for transmitting a specific control frame and a reception timer for receiving a response frame for each slave station device 2. The processor 12a of the master station apparatus 1 sets a value corresponding to the transmission cycle of the specific control frame in the transmission timer (step S101). As a result, the transmission timer starts.

The processor 12a determines whether or not the transmission condition of the specific control frame is satisfied (step S102). The transmission condition of the specific control frame includes the following three items, and when any one or more of the three items is satisfied, the transmission condition is satisfied.
(1) The master station device 1 is instructed by the management server 7 to set the slave station device 2.
(2) The transmission of the specific control frame has timed out (the transmission timer has expired).
(3) The reception of the response frame has timed out (the reception timer has expired).

If the transmission condition of the specific control frame is not satisfied (NO in step S102), the processor 12a executes step S102 again.

When the transmission condition of the specific control frame is satisfied (YES in step S102), the processor 12a uses the VLAN list 18a stored in the storage unit 18 to indicate the VLAN corresponding to the slave station device 2 to be transmitted of the specific control frame. Read the ID (step S103).

Next, the processor 12a creates a specific control frame having the above-described configuration (step S104). The read VIN ID is stored in the VIN tags 103 and 203 of the specific control frame. The processor 12a transmits the created specific control frame to the network 3 (step S105). The processor 12a sets a value corresponding to the reception period of the response frame in the reception timer (step S106).

See FIG. The specific control frame transmitted from the master station device 1 is transferred to the target slave station device 2 by the L2 switch 4. The processor 22a of the slave station device 2 determines whether or not a specific control frame has been received (step S201). In this process, it is determined whether or not the received frame is a specific control frame. The values of the destination address, length / type, and subtype are used for the determination. Receive if the destination address is a multicast destination address reserved for Ethernet OAM, the length / type value is the ether type specified in Link OAM, and the subtype is a value indicating OAM. It is determined that the frame is a specific control frame, and otherwise, the received frame is determined not to be a specific control frame.

If the specific control frame has not been received (NO in step S201), the processor 22a re-executes step S201.

When the specific control frame is received (YES in step S201), the processor 22a determines the type of the specific control frame (step S202). The value "0x00" indicating Information OAM is stored in the Code field of the Information OAM frame. The value "0xFE" indicating Organization Specific OAM is stored in the Code field of the Organization Specific OAM frame. The processor 22a refers to the Code field in the frame, and determines whether the type of the specific control frame is Information OAM or Organization Specific OAM.

When the type of the specific control frame is Information OAM (“Information OAM” in step S202), the processor 22a determines whether or not the specific control frame is a genuine frame (step S203). In this process, the values of OUI 107 and Vendor Specific Info 108 in the frame are referred to. The storage unit 28 of the slave station device 2 stores a genuine vendor identification number and a genuine certificate information. The certificate information stored in the storage unit 28 is the decrypted information. The processor 22a compares the value of the UI 107 in the frame with the vendor's identification information stored in the storage unit 28, and determines whether or not they match. Further, the processor 22a decodes the value of Vendor Specific Info 108 in the frame, compares the decoded value with the certificate information stored in the storage unit 28, and determines whether or not they match. If both the vendor's identification information and the certificate information match the values stored in the storage unit 28, the processor 22a determines that it is a genuine specific control frame, and at least one of the vendor's identification information and the certificate information. Does not match the value stored in the storage unit 28, it is determined that the specific control frame is invalid.

If the received specific control frame is not a genuine specific control frame (NO in step S203), the processor 22a returns to step S201.

When the received specific control frame is a genuine specific control frame (YES in step S203), the processor 22a uses the MAC address and the VLAN tag of the master station device 1 stored in the source addresses 102 and 202 of the specific control frame. The VLAN ID (VLAN ID assigned to the own device) stored in 103 and 203 is written to the storage unit 28 (step 204). Further, the processor 22a creates a response frame, which is an Information OAM frame, as described above (step S205).

When the type of the specific control frame is Organization Specific OAM (“Organization Specific OAM” in step S202), the processor 22a determines whether or not the specific control frame is a genuine frame (step S206). In this process, the value of UI207 in the frame is referred to. The processor 22a compares the value of the UI 207 in the frame with the vendor's identification information stored in the storage unit 28, and determines whether or not they match. When the vendor identification information matches the value stored in the storage unit 28, the processor 22a determines that it is a genuine specific control frame, and when the vendor identification information does not match the value stored in the storage unit 28. , It is determined that the specific control frame is invalid.

If the received specific control frame is not a genuine specific control frame (NO in step S206), the processor 22a returns to step S201.

When the received specific control frame is a genuine specific control frame (YES in step S206), the processor 22a uses the MAC address and the VLAN tag of the master station device 1 stored in the source addresses 102 and 202 of the specific control frame. The VLAN ID (VLAN ID assigned to the own device) stored in 103 and 203 is written to the storage unit 28 (step 207).

The processor 22a changes the setting of its own device according to the setting information included in the specific control frame (step S208). For example, when the VLAN ID for the user frame is stored in the data field of the specific control frame, the processor 22a updates the VLAN ID of the VLAN table stored in the storage unit 28.

The processor 22a creates a response frame, which is an Organization Specific OAM frame, as described above (step S209). For example, the data field of this response frame stores information on the success or failure of the setting.

The processor 22a transmits the created response frame to the network 3 (step S210). After that, the processor 22a returns to step S201.

See FIG. 9 again. After step S106, the processor 12a of the master station apparatus 1 determines whether or not a response frame has been received (step S107). When the response frame has not been received (NO in step S107), the processor 12a determines whether the reception timer has reached the timeout time, that is, has timed out (step S108). If the receive timer has not timed out (NO in step S108), the processor 12a returns to step S107.

If the receive timer has timed out (YES in step S108), the processor 12a returns to step S102. In this case, the above (3) Time-out for receiving the response frame is satisfied. Therefore, the process proceeds to YES in step S102.

When the response frame is received (YES in step S107), the processor 12a determines whether or not the response frame is a genuine frame (step S109). Since this process is the same as the above-mentioned steps S204 and S206, the description thereof will be omitted.

If the received response frame is not a genuine response frame (NO in step S109), the processor 12a returns to step S107.

When the received response frame is a genuine response frame (YES in step S109), the processor 12a has the VLAN ID stored in the VLAN tags 103 and 203 of the response frame stored in the storage unit 18 in the VLAN list 18a. It is determined whether or not it matches the VLAN ID registered in (step S110).

If the VLAN ID stored in the VLAN tags 103 and 203 of the response frame does not match the VLAN ID registered in the VLAN list 18a (NO in step S110), the processor 12a returns to step S107.

When the VLAN ID stored in the VLAN tags 103 and 203 of the response frame matches the VLAN ID registered in the VLAN list 18a (YES in step S110), the processor 12a identifies the slave station device 2 by the VLAN ID. (Step S111). Further, the processor 12a updates the state information of the slave station device 2 with the value included in the response frame (step S112). Further, the processor 12a returns to step S101.

[5. Modification example]
[5-1. First modification]
In the first modification, the VLAN ID of the slave station device 2 can be changed. For example, the management server 7 instructs the master station device 1 to change the VLAN ID of the slave station device 2. At this time, the management server 7 designates the number of the slave station device 2 whose VLAN ID is to be changed and the new VLAN ID. The processor 12a of the master station device 1 rewrites the VLAN ID corresponding to the number of the designated slave station device to a new VLAN ID in the VLAN list 18a stored in the storage unit 18.

In the master station device 1, the state information of the slave station device 2 whose VLAN ID has been changed does not change before and after the change of the VLAN ID. For example, when the session state between the master station device 1 and the slave station device 2 is a state in which the sessions of both devices are established and the VLAN ID is changed, the master station device 1 and the slave station device 2 Session is not changed to the unestablished state. The processor 12a can create a specific control frame for the slave station device to be transmitted and transmit the specific control frame without changing the session state. Flags 106 and 206 of this specific control frame store "80" indicating a state in which both device sessions have been established. As a result, it is not necessary to perform a new communication process (handshake) for establishing a session between the master station device 1 and the slave station device 2.

[5-2. Second variant]
In the second modification, the specific control frame is an Ethernet OAM frame instead of a Link OAM frame. As a specific example, an Ethernet VSM (Vendor Specific OAM Message) frame is used.

FIG. 11 is a diagram showing an example of the configuration of a specific control frame which is an Ethernet VSM frame. The Ethernet VSM frame has fields such as a destination address 301, a source address 302, a VLAN tag 303, an ether type 304, a subtype (OpCode) 305, and a Vendor Specific Data 306. The Vendor Specific Data 306 may have the same format as each field of the flag to data of the Link OAM frame described above (not shown).

In the specific control frame transmitted from the master station apparatus 1, the multicast destination address (01-80-C2-00-00-3x) of the Ethernet OAM is stored in the destination address 301. Further, the source address 302 stores the MAC address of the master station device 1, and the VLAN tag 303 stores the VLAN ID assigned to the target slave station device 2. The ether type 304 stores the ether type "0x8902" specified in the Ethernet OAM, and the subtype 305 stores the value "0x51" indicating VSM. In this modification, the values of the destination address 301, the ether type 304, and the subtype 305 are used to identify the specific control frame. That is, the frame where the value of the destination address 301 is the multicast destination address of the Ethernet OAM, the value of the ether type is the ether type "0x8902" specified in the Ethernet OAM, and the value of the subtype is "0x51" indicating VSM. Is determined to be a specific control frame.

In the specific control frame transmitted from the master station device 1, the Vendor Specific Data 306 contains the value indicating the session state stored in the flags 106 and 206 described above, the vendor-specific identification information stored in the UI 107, and the Vendor Specific Info 108. The encrypted certificate information stored in is stored. Vendor-specific identification information and certificate information are used to determine whether or not the specific control frame is genuine.

In the response frame transmitted from the slave station device 2, the MAC address of the master station device 1 is stored in the destination address 301. Further, the source address 302 stores the MAC address of the slave station device 2 (own device) that is the source of the response frame. The values of the VLAN tag 303, the ether type 304, and the subtype 305 are the same as those of the specific control frame. That is, the VLAN tag 303 stores the VLAN ID assigned to the own device, the ether type 304 stores the ether type "0x8902" specified in the Ethernet OAM, and the subtype 305 indicates VSM. The value "0x51" is stored.

The configuration of the Vendor Specific Data 306 in the response frame transmitted from the slave station device 2 is the same as the configuration of the Vendor Specific Data 306 in the specific control frame. That is, in the Vendor Specific Data 306, the value indicating the session state stored in the flags 106 and 206 described above, the vendor-specific identification information stored in the UI 107, and the encrypted certificate information stored in the Vendor Specific Info 108. Is stored. As the session state, the latest value at that time is stored. The vendor-specific identification information and certificate information store the same values as the specific control frame. However, the certificate information does not have to be the same value as the specific control frame as long as it is information that illuminates that the device is a legitimate slave station device.

[5-3. Other variants]
The first half of the MAC address (top 3 octets) is vendor-specific identification information. The vendor identification information included in this MAC address may be used to identify a specific control frame (including a response frame). In this case, the information of OUI 107 and 207 may not be used for identifying the specific control frame.

In the above-described embodiment, the slave station device 2 recognizes the VLAN ID of its own device by the specific control frame received, but the present invention is not limited to this. The slave station device 2 may recognize the VLAN ID of its own device by a control frame other than the specific control frame.

In the above-described embodiment, the certificate information is stored in the Vendor Specific Info 108 in the specific control frame which is the Information OAM frame. Well-known authentication techniques can be used for this certificate information. The information stored in the Vendor Specific Info 108 may not be the certificate information, but may be, for example, vendor-defined information, or the information may not be stored in the Vendor Specific Info 108.

[6. effect]
The communication system 10 includes a master station device 1 and a slave station device 2. The slave station device 2 is connected to the master station device 1 via a VLAN. The master station device 1 includes a storage unit 18 and a control unit (first control unit) 12. The storage unit 18 stores a VLAN ID for identifying the VLAN to which the slave station device 2 belongs for each slave station device 2. The control unit 12 creates a specific control frame for controlling the slave station device 2. The specific control frame includes the VLAN tags 103 and 203 in which the VLAN ID is stored. The slave station device 2 includes a control unit (second control unit) 22. The control unit 22 processes the specific control frame and creates a response frame. The control unit 22 determines whether or not the receiving frame is a specific control frame by referring to the destination address 101, 201 and the length / type 104, 204 regardless of the information of the VLAN tags 103 and 203 in the receiving frame. judge. Since the VLAN tags 103 and 203 are not used for identifying the specific control frame in the slave station device 2, it is not necessary to set the VLAN information in the slave station device 2. Therefore, it is possible to reduce the work of setting the VLAN.

The specific control frame may include a multicast destination address reserved for Ethernet OAM as the destination address. By using the multicast destination address of the Ethernet OAM that is supposed to use the VLAN tag, the child to which the VLAN ID specified by the VLAN tags 103 and 203 is assigned without discarding the specific control frame on the L2 switch 4. The specific control frame reaches the station device 2. Therefore, it is not necessary to manage the address of the slave station device 2 in the master station device 1, and it is possible to further reduce the work of setting the VLAN.

The specific control frame may include an ether type specified in Link OAM or an Ethernet type specified in Ethernet OAM. As a result, whether or not the slave station device stores the ether type (0x8809) specified in the Link OAM or the ether type (0x8902) specified in the Ethernet OAM in the length / type field of the received frame. A specific control frame can be identified based on.

The specific control frame may include an OAM subtype as an ether type subtype. The control unit 22 may determine whether or not the received frame is a specific control frame by further referring to the subtype. By using the OAM subtype (0x03) for identifying the specific control frame in the slave station device 2, more accurate identification of the specific control frame becomes possible.

The control unit 22 may determine whether or not the specific control frame is a genuine specific control frame based on the vendor code included in the specific control frame. As a result, the slave station device 2 can identify an illegal specific control frame, and it is possible to prevent the slave station device 2 from being illegally set.

The specific control frame may include a Vendor Specific Info field that contains certificate information for proving the authentic specific control frame. The control unit 22 may determine whether or not the specific control frame is a genuine specific control frame based on the information stored in the Vendor Specific Info field included in the specific control frame. As a result, the slave station device 2 can more accurately identify an illegal specific control frame.

Even if the control unit 22 includes the source addresses 102 and 202 of the specific control frame as the destination addresses 101 and 201 and creates a response frame including the same VLAN tags 103 and 203 as the VLAN tags 103 and 203 of the specific control frame. good. Even if the VLAN ID is not set in advance in the slave station device 2, the slave station device 2 can create a response frame and transmit the response frame from the slave station device 2 to the master station device 1.

When the VLAN ID of the slave station device 2 for which the session is established with the master station device 1 is changed, the control unit 12 maintains the session state and stores the changed VLAN IDs 103 and 203. You may create a specific control frame including. In the present disclosure, the slave station device 2 identifies a specific control frame without using a VLAN ID. Therefore, even if the VLAN ID is changed, it is not necessary to change the session state with the master station device 1 in the slave station device 2. With the above configuration, when the VLAN ID assigned to the slave station device 2 changes, communication processing (handshake) for establishing a new session is performed between the master station device 1 and the slave station device 2. No need.

The slave station device 2 may further include a storage unit 28. When the control unit 22 receives the specific control frame transmitted from the master station device 1, the control unit 22 may store the VLAN ID included in the received specific control frame in the storage unit 28. When the control unit 22 creates a control frame to be transmitted from the slave station device 2 to the master station device 1, the control unit 22 creates a control frame including the VLAN tags 103 and 203 in which the VLAN ID stored in the storage unit 28 is stored. May be good. As a result, even if the operator does not set the VLAN ID in the slave station device 2, the slave station device 2 creates a control frame including the VLAN tags 103 and 203, and the control frame is transferred from the slave station device 2 to the master station device 1. Can be sent to.

The specific control frame may be a Link OAM frame or an Ethernet OAM frame. As a result, the master station apparatus 1 can control the slave station apparatus 2 by using the Link OAM frame or the Ethernet OAM frame without setting the VLAN information in the slave station apparatus 2.

The master station device 1 is connected to the slave station device 2 via a VLAN. The master station device 1 includes a storage unit 18 and a control unit (first control unit) 12. The storage unit 18 stores a VLAN ID for identifying the VLAN to which the slave station device belongs for each slave station device 2. The control unit 12 creates a specific control frame for controlling the slave station device 2. The specific control frame includes the VLAN tags 103 and 203 in which the VLAN ID is stored. The master station device 1 does not set a VLAN ID in the slave station device 2 before transmitting the specific control frame to the slave station device 2. Since the VLAN information is not set in the slave station device, it is possible to reduce the work of setting the VLAN.

[7. Supplement]
The embodiments disclosed this time are exemplary in all respects and are not restrictive. The scope of rights of the present invention is shown by the scope of claims, not the embodiments described above, and includes the meaning equivalent to the scope of claims and all modifications within the scope thereof.

1 Master station device 2 Slave station device 3 Network 4 L2 switch 5 Upper network 6 Lower network 7 Management server 10 Communication system 11 Upper interface unit 12 Control unit (1st control unit)
12a, 22a Processor 12b, 22b Non-volatile memory 12c, 22c Volatile memory 12d, 22d Input / output unit 12e Master station program 13,23 First processing unit 13a, 14a, 23b, 24a VLAN determination unit 13b, 23a Control frame determination unit 14,24 2nd processing unit 14b Confluence unit 15,25 Opposite side interface unit 16,26 Upstream buffer 17,27 Downstream buffer 18,28 Storage unit 18a VLAN list 19 External interface unit 21 Lower side interface unit 22 Control unit (second) Control unit)
22e Slave station program 24b Confluence 101,201,301 Destination address 102,202,302 Source address 103,203,303 VLAN tag 104,204 Length / type 105,205,305 Subtype (OpCode)
106,206 Flag 107,207 OUI (Organizationally Unique Identifier)
108 Vendor Specific Info
304 Ethertype 306 Vendor Specific Data

Claims (13)

With the master station device,
A slave station device connected to the master station device via a VLAN,
It is a communication system equipped with
The master station device is
For each slave station device, a storage unit for storing a VLAN ID for identifying the VLAN to which the slave station device belongs, and a storage unit.
A first control unit that creates a specific control frame for controlling the slave station device, and
Including
The specific control frame includes a VLAN tag in which the VLAN ID is stored.
The slave station device includes a second control unit that processes the specific control frame and creates a response frame.
The second control unit determines whether or not the receiving frame is the specific control frame by referring to the destination address and the ether type regardless of the information of the VLAN tag in the receiving frame.
Communications system. The specific control frame includes a multicast destination address reserved for Ethernet OAM as a destination address.
The communication system according to claim 1. The specific control frame includes an ether type specified in Link OAM or an Ethernet type specified in Ethernet OAM.
The communication system according to claim 1 or 2. The specific control frame includes a subtype of OAM as a subtype of the ether type.
The second control unit further refers to the subtype to determine whether or not the receiving frame is the specific control frame.
The communication system according to claim 3. The second control unit determines whether or not the specific control frame is a genuine specific control frame based on the vendor code included in the specific control frame.
The communication system according to any one of claims 1 to 4. The specific control frame includes a field in which certificate information for certifying a genuine specific control frame is stored.
The second control unit determines whether or not the specific control frame is a genuine specific control frame based on the information stored in the field included in the specific control frame.
The communication system according to any one of claims 1 to 5. The second control unit creates the response frame including the source address of the specific control frame as a destination address and the same VLAN tag as the VLAN tag of the specific control frame.
The communication system according to any one of claims 1 to 6. The first control unit includes a VLAN tag in which the changed VLAN ID is stored while maintaining the session state when the VLAN ID of the slave station device having a session established with the master station device is changed. Create a specific control frame,
The communication system according to any one of claims 1 to 7. The slave station device further includes a storage unit and includes a storage unit.
When the second control unit receives the specific control frame transmitted from the master station device, the second control unit stores the received VLAN ID included in the specific control frame in the storage unit.
When the second control unit creates a control frame to be transmitted from the slave station device to the master station device, the second control unit creates a control frame including a VLAN tag in which the VLAN ID stored in the storage unit is stored.
The communication system according to any one of claims 1 to 8. The specific control frame is a Link OAM frame or an Ethernet OAM frame.
The communication system according to any one of claims 1 to 9. A master station device that is connected to a slave station device via a VLAN.
For each slave station device, a storage unit for storing a VLAN ID for identifying the VLAN to which the slave station device belongs, and a storage unit.
A control unit that creates a specific control frame for controlling the slave station device, and
Including
The specific control frame includes a VLAN tag in which the VLAN ID is stored.
The VLAN ID is not set in the slave station device before the specific control frame is transmitted to the slave station device.
Master station device. It is a slave station device connected to the master station device via VLAN, and is a slave station device.
A control unit that processes a specific control frame transmitted from the master station device and creates a response frame is provided.
The specific control frame includes a VLAN tag containing a VLAN ID for identifying the VLAN to which the slave station device belongs.
The control unit determines whether or not the received frame is the specific control frame by referring to the destination address and the ether type regardless of the information of the VLAN tag in the received frame.
Slave device. A computer program for operating a computer as a slave station device connected to a master station device via a VLAN.
On the computer
A step of processing a specific control frame transmitted from the master station device and creating a response frame is executed.
The step includes determining whether or not the received frame is the specific control frame by referring to the destination address and the ether type regardless of the information of the VLAN tag in the received frame.
Computer program.

Images