JP6833072B2 - Relay device, end judgment method, and end judgment program - Google Patents

Description

The present invention relates to a relay device, an end determination method, and an end determination program.

PPPoE (Point-to-Point Protocol over Ethernet (registered trademark)) is known as a data link layer protocol. The client device and the BAS (Broadband Access Server) establish a session via a device having a bridging function (hereinafter, a bridge device). When a power failure or the like occurs, the bridge device needs to terminate the session based on the session ID (identifier) managed by the client device and the BAS.

Here, a technique for terminating a session has been proposed (see, for example, Patent Document 1). For example, when the PPPoE bridge device of Patent Document 1 receives an LCP (Link Control Protocol) Echo request packet after turning off the PPPoE bridge function, the source of the LCP Echo request packet is a PADT (PPPoE Active Packet Display). To end the session.

JP-A-2007-116348

By the way, when the BAS establishes a session with the client device, the BAS transmits an LCP Echo request packet addressed to the client device to the bridge device at regular intervals.
The LCP Echo request packet transmitted by BAS may be received by another bridging device due to flooding or the like. According to the above technique, when the other bridge device receives the LCP Echo request packet when the bridge function of the other bridge device is OFF, the other bridge device transmits the PADT packet to the BAS. By receiving the PADT packet, the BAS ends the session established by the client device and the BAS. As described above, in the above technique, the session may be terminated by mistake.

An object of the present invention is to prevent accidental termination of a session.

A relay device according to one aspect of the present invention is provided. By having a bridge function, the relay device relays information transmitted and received between the first client device and the information processing device. Further, the relay device includes a storage unit that stores the first information that is information for identifying the first client device, and a plurality of relay devices including the first client device when the bridge function is stopped. Connection confirmation information including the second information which is the information for confirming the connection with the second client device which is one of the client devices and the information for identifying the second client device. Is received from the information processing device, it is determined whether or not the first information and the second information match, and if it is determined that they do not match, the second client device and the information processing device determine. It has a control unit that controls not to instruct the information processing apparatus to end an established session.

According to the present invention, it is possible to prevent the session from being accidentally terminated.

It is a figure which shows the communication system of Embodiment 1. It is a figure which shows the main hardware composition which the bridge apparatus of Embodiment 1 has. It is a functional block diagram which shows the structure of the bridge apparatus of Embodiment 1. FIG. It is a figure which shows the format of a PADI packet. It is a figure which shows the format of the LCP Echo Request packet. It is a figure which shows the format of a PADT packet. It is a figure which shows the bridge table. It is a figure which shows the MAC address table. It is a sequence diagram (the 1) which shows the example of the session end processing of Embodiment 1. FIG. It is a sequence diagram (the 2) which shows the example of the session end processing of Embodiment 1. FIG. It is a flowchart which shows the session end processing executed by the bridge apparatus of Embodiment 1. FIG. It is a functional block diagram which shows the structure of the bridge device of Embodiment 2. It is a sequence diagram which shows the example of the session end processing of Embodiment 2. It is a functional block diagram which shows the structure of the bridge device of Embodiment 3. It is a figure which shows the format of the ARP packet. It is a sequence diagram which shows the example of the session end processing of Embodiment 3.

Hereinafter, embodiments will be described with reference to the drawings. The following embodiments are merely examples, and various modifications can be made within the scope of the present invention.

Embodiment 1.
FIG. 1 is a diagram showing a communication system according to the first embodiment. Communication systems include bridge devices 100,500, BAS200, client devices 300,301,302,303, and ISPs (Internet Service Providers) 400,401,402.

The bridging devices 100 and 500 are connected to the BAS 200 via the optical network 10. Further, the bridge device 100 connects to the client device 300 via a network. The bridge device 500 connects to the client devices 301 and 302 via a wired network. The bridge device 500 connects to the client device 303 via a wireless network.
The bridging devices 100 and 500 may be referred to as PPPoE bridging devices. The client devices 300, 301, 302, 303 may be expressed as PPPoE client devices.

An ONU (Optical Network Unit) exists between the bridge device 100 and the optical line network 10 and between the bridge device 500 and the optical line network 10. In FIG. 1, ONU is omitted. Further, the bridging devices 100 and 500 may include an ONU function.

The bridging devices 100 and 500 are devices having a bridging function. For example, the bridge device 100 relays information transmitted and received between the BAS 200 and the client device 300 by having a bridge function. The bridge devices 100 and 500 are also referred to as relay devices. The bridge devices 100 and 500 are devices that execute the end determination method.
The client devices 300 to 303 are computers used by the user. The client devices 300 to 303 are connected to the BAS 200 via the bridge devices 100 and 500 and the optical network 10. The client device 300 is also referred to as a first client device. The client device 300 may also be referred to as a second client device. Any of the client devices 301 to 303 is also referred to as a second client device.

The BAS200 is called an information processing device. BAS200 can be connected to ISP400-402. ISPs 400 to 402 authenticate to connect to networks 20, 21, 22. For example, the ISP 400 authenticates the client device 300 to connect to the network 20. After the ISP 400 authenticates, the client device 300 can connect to the network 20. In the following description, it is assumed that the client device 300 is connected to the network 20.

Next, the main hardware configurations of the bridge devices 100 and 500 will be described.
FIG. 2 is a diagram showing a main hardware configuration included in the bridge device of the first embodiment. The bridging device 100 includes a processor 101, a volatile storage device 102, and a non-volatile storage device 103.

The processor 101 controls the entire bridge device 100. For example, the processor 101 is a CPU (Central Processing Unit), an FPGA (Field Programmable Gate Array), or the like. The processor 101 may be a multiprocessor. The bridging device 100 may be realized by a processing circuit, or may be realized by software, firmware, or a combination thereof.

The volatile storage device 102 is the main storage device of the bridge device 100. For example, the volatile storage device 102 is a RAM (Random Access Memory). The non-volatile storage device 103 is an auxiliary storage device of the bridge device 100. For example, the non-volatile storage device 103 is an SSD (Solid State Drive) or the like.

The bridge device 500, like the bridge device 100, has a processor, a volatile storage device, and a non-volatile storage device.

In the following description, the processing performed between the bridge device 100, the BAS 200, and the client device 300 will be described. Further, the process is the same as the process performed between the bridge device 500, the BAS200, and the client devices 301 to 303. Therefore, the description of the processing performed between the bridge device 500, the BAS200, and the client devices 301 to 303 will be omitted.

FIG. 3 is a functional block diagram showing the configuration of the bridge device according to the first embodiment. The bridge device 100 includes a control unit 110, a bridge function unit 120, a table storage unit 130, a storage unit 140, a storage unit 150, a WAN (Wide Area Network) port 160, and a LAN (Local Area Network) port 170. The storage unit 140 may be expressed as a MAC (Media Access Control) address storage unit. The MAC address is also called a physical address.

The bridging device 100 may have a plurality of LAN ports. For example, the bridge device 100 communicates with a plurality of client devices via a plurality of LAN ports like the bridge device 500. Further, the bridging device 100 may have a wireless interface. As a result, the bridge device 100 can wirelessly communicate with the client device like the bridge device 500.

The control unit 110 includes a packet monitoring unit 111, a packet identification unit 112, a data acquisition unit 113, a packet generation unit 114, a transmission / reception unit 115, and an end determination unit 116.
A part or all of the packet monitoring unit 111, the packet identification unit 112, the data acquisition unit 113, the packet generation unit 114, the transmission / reception unit 115, the end determination unit 116, and the bridge function unit 120 may be realized by the processor 101. A part or all of the packet monitoring unit 111, the packet identification unit 112, the data acquisition unit 113, the packet generation unit 114, the transmission / reception unit 115, the end determination unit 116, and the bridge function unit 120 are modules of a program executed by the processor 101. It may be realized. The program is stored in the volatile storage device 102 or the non-volatile storage device 103. For example, the program is an end determination program.

The table storage unit 130 and the storage unit 150 are realized as storage areas reserved in the volatile storage device 102. The storage unit 140 is realized as a storage area secured in the non-volatile storage device 103.
The control unit 110 communicates with the BAS 200 via the WAN port 160. The control unit 110 and the bridge function unit 120 communicate with the client device 300 via the LAN port 170.

The packet monitoring unit 111 monitors the packets transmitted by the BAS 200 and the client device 300. The packet identification unit 112 identifies the packet. The data acquisition unit 113 acquires the MAC address and the session ID from the packets transmitted by the BAS 200 and the client device 300. The packet generation unit 114 generates a packet. For example, the packet generation unit 114 generates a PADT packet. Further, the PADT packet may be expressed as information indicating the end of the session.

The transmission / reception unit 115 transmits the packet generated by the packet generation unit 114 to the BAS 200 and the client device 300. Further, the transmission / reception unit 115 receives the packets transmitted by the BAS 200 and the client device 300. For example, the transmission / reception unit 115 receives an LCP Echo Request packet from the BAS 200 and the client device 300. The LCP Echo Request packet is also referred to as connection confirmation information. The connection confirmation information is information for confirming the connection.

The function of the end determination unit 116 will be described in detail later. The bridge function unit 120 has a function of connecting the BAS 200 and the client device 300. The bridge function unit 120 receives a PADI (PPPoE Active Discovery Initiation) packet from the client device 300.
The table storage unit 130, the storage unit 140, and the storage unit 150 store various information. What kind of information is stored in the table storage unit 130, the storage unit 140, and the storage unit 150 will be described in detail later.

Next, the format of the PADI packet will be described.
FIG. 4 is a diagram showing the format of the PADI packet. FIG. 4 shows the field names of the PADI packet format 601. The PADI packet contains an Ethernet header, a PPPoE payload, and a frame check sequence. The Ethernet header contains the destination MAC address, the source MAC address, and the ether type.

The field length of the destination MAC address is 6 octets. The field length of the source MAC address is 6 octets. The Ethertype field length is 2 octets. The field length of the frame check sequence is 4 octets.

Next, the format of the LCP Echo Request packet will be described.
FIG. 5 is a diagram showing the format of the LCP Echo Request packet. FIG. 5 shows the field names of the LCP Echo Request packet format 602.

The LCP Echo Request packet includes an Ethernet header, a PPPoE header, a PPPoE payload, and a frame check sequence. The Ethernet header contains the destination MAC address, the source MAC address, and the ether type. The PPPoE header contains the version, type, code, session ID of the PPPoE session, and the data length of the PPPoE payload. The PPPoE payload contains data from the PPP protocol, LCP Echo Request.

The field length of the destination MAC address is 6 octets. The field length of the source MAC address is 6 octets. The Ethertype field length is 2 octets.

The field length of version and type is 1 octet. The field length of the code is 1 octet. The field length of the session ID is 2 octets. The field length of the data length is 2 octets.
The field length of the PPP protocol is 2 octets. The field length of the frame check sequence is 4 octets.

Next, the format of the PADT packet will be described.
FIG. 6 is a diagram showing the format of the PADT packet. FIG. 6 shows the field names of the PADT packet format 603.

The PADT packet includes an Ethernet header, a PPPoE header, a PPPoE payload, and a frame check sequence. The Ethernet header contains the destination MAC address, the source MAC address, and the ether type. The PPPoE header contains the version, type, code, session ID of the PPPoE session, and the data length of the PPPoE payload.

The field length of the destination MAC address is 6 octets. The field length of the source MAC address is 6 octets. The Ethertype field length is 2 octets.
The field length of version and type is 1 octet. The field length of the code is 1 octet. The field length of the session ID is 2 octets. The field length of the data length is 2 octets. The field length of the frame check sequence is 4 octets.

Next, the information stored in the table storage unit 130 will be described.
FIG. 7 is a diagram showing a bridge table. The bridge table 131 is stored in the table storage unit 130.
The bridge table 131 is No. It has items (ie, item number), session ID, and MAC address. The MAC address item includes the client device and BAS items.

No. Item indicates an identifier. The session ID item indicates information that identifies the session. The item of the client device indicates the MAC address of the client device to which the bridge device 100 is connected. The BAS item indicates the MAC address of BAS200.

The bridge table 131 is also referred to as bridge information. For example, the bridge information may be expressed as information used when relaying information transmitted / received between the BAS 200 and the client device 300.

Next, the information stored in the storage unit 140 will be described.
FIG. 8 is a diagram showing a MAC address table. The MAC address table 141 is stored in the storage unit 140.
The MAC address table 141 shows No. (Ie, item number), and the item of the client device.

No. Item indicates an identifier. The item of the client device indicates the MAC address of the client device to which the bridge device 100 is connected.

Next, an outline of the session end processing performed between the bridge device 100, the BAS 200, and the client device 300 will be described with reference to a sequence diagram.
FIG. 9 is a sequence diagram (No. 1) showing an example of the session end processing of the first embodiment. 9 and 10 refer to FIGS. 1, 3 to 8.

(Step S101) The bridge device 100 is turned on by the user's operation. As a result, the function of the bridge function unit 120 of the bridge device 100 becomes effective.
The bridge device 100 may be turned off by the user's operation. Further, the bridge device 100 may be in a state in which the power supply of the bridge device 100 is ON even when the bridge function is OFF.

(Step S102) The client device 300 transmits a PADI packet to the bridge device 100 in order to establish a session with the BAS 200. Further, the PADI packet may be expressed as information for searching for BAS200.
(Step S103) The bridge function unit 120 of the bridge device 100 acquires the MAC address of the client device 300 from the PADI packet. The bridge function unit 120 of the bridge device 100 creates a bridge table 131. The bridge function unit 120 of the bridge device 100 registers the MAC address of the client device 300 in the item of the client device of the bridge table 131.

(Step S104) The bridge function unit 120 of the bridge device 100 registers the MAC address of the client device 300 in the item of the client device in the MAC address table 141. By registering the MAC address of the client device 300 in the MAC address table 141, the bridge device 100 can prevent the information registered in the MAC address table 141 from being lost even in the event of a power failure or the like.

In this way, when the bridge device 100 establishes the session, the MAC address of the client device 300 is registered in the bridge table 131 and the MAC address table 141. Here, the MAC address of the client device 300 is also referred to as the first information.

Here, the bridge device 100 can be connected to an unspecified number of client devices. For example, the bridge device 100 can be connected to an unspecified number of client devices by having a wireless interface. When the bridge device 100 can connect to an unspecified number of client devices, the bridge device 100 registers the MAC addresses of the unspecified number of client devices in the MAC address table 141. However, the bridge device 100 may not have enough storage capacity of the storage unit 140 to register the MAC addresses of all the client devices in the MAC address table 141. Therefore, when the bridge function unit 120 of the bridge device 100 registers a new MAC address in the MAC address table 141, if the amount of data stored in the storage unit 140 is equal to or greater than the threshold value, the bridge function unit 120 is registered in the MAC address table 141. Among the MAC addresses, the MAC address with the earliest registered time is deleted, and the newly acquired MAC address is registered in the MAC address table 141.

(Step S105) The transmission / reception unit 115 of the bridge device 100 transmits a PADI packet to the BAS 200.
(Step S106) The BAS 200 and the client device 300 perform PPPoE authentication via the bridge device 100. As a result, a session is established between the BAS 200 and the client device 300.

Here, the bridge function unit 120 of the bridge device 100 can acquire the session ID and the MAC address of the BAS200 from the packet transmitted by the BAS200 or the client device 300 in the process of performing PPPoE authentication. The bridge function unit 120 of the bridge device 100 registers the session ID in the session ID item of the bridge table 131. The bridge function unit 120 of the bridge device 100 registers the MAC address of the BAS 200 in the BAS item of the bridge table 131.

In step S104, the case where the MAC address of the client device 300 is registered in the MAC address table 141 has been described. However, the bridge function unit 120 of the bridge device 100 MACs the MAC address of the client device 300 included in the information transmitted by the BAS 200 or the client device 300 until the session is established between the BAS 200 and the client device 300. It may be registered in the address table 141.

After the session is established, the BAS 200 and the client device 300 transmit LCP Echo Request packets at regular intervals in order to confirm the connection status.
(Step S107) A power failure occurs. The bridge device 100 loses the bridge table 131 due to a power failure. The disappearance of the bridge table 131 is the same as turning off the bridge function. Further, when the bridge function is turned off, the bridge function is stopped.
Further, step S107 may be considered as a case where the bridge function is turned off by the operation of the user.

Here, if the bridge table 131 disappears, the client device 300 cannot connect to the network 20. In order for the client device 300 to connect to the network 20, it is necessary to establish a session again between the BAS 200 and the client device 300. However, since the previous session remains in the BAS 200 and the client device 300, a new session cannot be established. That is, since the BAS 200 and the client device 300 are in a state of duplicate login, a new session cannot be established. Therefore, the bridge device 100 ends the previous session. A method of ending the previous session will be described with reference to FIG.
(Step S108) The bridge device 100 is restarted.

FIG. 10 is a sequence diagram (No. 2) showing an example of the session end processing of the first embodiment.
(Step S111) The packet monitoring unit 111 of the bridge device 100 monitors the BAS 200 and the client device 300 to transmit the LCP Echo Request packet.
(Step S112) The BAS 200 transmits an LCP Echo Request packet to the bridge device 100. The information registered in the destination MAC address of the LCP Echo Request packet is also referred to as second information.

(Step S113) The client device 300 transmits an LCP Echo Request packet to the bridge device 100.
(Step S114) The packet identification unit 112 of the bridge device 100 identifies that the packet received from the BAS 200 is an LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the MAC address of the BAS 200 from the source MAC address of the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the MAC address of the client device 300 from the destination MAC address of the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the session ID from the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 stores the acquired MAC address of the BAS 200, the MAC address of the client device 300, and the session ID in the storage unit 150.

The packet identification unit 112 of the bridge device 100 identifies that the packet received from the client device 300 is an LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the MAC address of the client device 300 from the source MAC address of the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the MAC address of the BAS 200 from the destination MAC address of the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 acquires the session ID from the LCP Echo Request packet. The data acquisition unit 113 of the bridge device 100 stores the acquired MAC address of the BAS 200, the MAC address of the client device 300, and the session ID in the storage unit 150.

The end determination unit 116 of the bridge device 100 compares the MAC address stored in the storage unit 150 with the MAC address registered in the MAC address table 141. This will be described in detail. The end determination unit 116 of the bridge device 100 compares the destination MAC address included in the LCP Echo Request packet received from the BAS 200 with the MAC address registered in the MAC address table 141.

In FIG. 10, it is assumed that the destination MAC address included in the LCP Echo Request packet received from the BAS200 and the MAC address registered in the MAC address table 141 match. The case of mismatch will be described in detail later.

(Step S115) The packet generation unit 114 of the bridge device 100 generates a first PADT packet and a second PADT packet based on the information stored in the storage unit 150. This will be described in detail.
The packet generation unit 114 of the bridging device 100 generates the first PADT packet based on the information of the LCP Echo Request packet received from the BAS 200. For example, the packet generation unit 114 of the bridge device 100 registers the MAC address of the BAS 200 as the destination MAC address of the first PADT packet. The packet generation unit 114 of the bridge device 100 registers the MAC address of the client device 300 in the source MAC address of the first PADT packet. The packet generation unit 114 of the bridging device 100 registers the session ID included in the LCP Echo Request packet received from the BAS 200 in the session ID of the first PADT packet.

The packet generation unit 114 of the bridge device 100 generates a second PADT packet based on the information of the LCP Echo Request packet received from the client device 300. For example, the packet generation unit 114 of the bridge device 100 registers the MAC address of the client device 300 in the destination MAC address of the second PADT packet. The packet generation unit 114 of the bridge device 100 registers the MAC address of the BAS 200 as the source MAC address of the second PADT packet. The packet generation unit 114 of the bridge device 100 registers the session ID included in the LCP Echo Request packet received from the client device 300 in the session ID of the second PADT packet.
Further, the packet generation unit 114 of the bridge device 100 may generate a second PADT packet based on the information of the LCP Echo Request packet received from the BAS 200.

(Step S116) The transmission / reception unit 115 of the bridge device 100 transmits the first PADT packet to the BAS 200.
(Step S117) The transmission / reception unit 115 of the bridge device 100 transmits a second PADT packet to the client device 300.

(Step S118) The packet monitoring unit 111 of the bridge device 100 monitors the BAS 200 and the client device 300 to transmit the PADT packet.
(Step S119) The BAS 200 transmits a PADT packet to the bridging device 100.

(Step S120) The client device 300 transmits the PADT packet to the bridge device 100.
(Step S121) In the end determination unit 116 of the bridge device 100, the session ID included in the first and second PADT packets is the same as the session ID included in the PADT packet received from the BAS 200 and the client device 300. It is determined whether or not it is. If the same is true, the end determination unit 116 of the bridge device 100 detects that the session has ended in the BAS 200 and the client device 300.

Next, the session end processing executed by the bridge device 100 will be described with reference to a flowchart.
FIG. 11 is a flowchart showing a session end process executed by the bridge device of the first embodiment. For a description of FIG. 11, see FIGS. 1, 3, 5, 6, 8, and 10. Further, FIG. 11 will be described from the time when the BAS 200 and the client device 300 transmit the LCP Echo Request packet (that is, the time of steps S112 and 113). The state of the bridge device 100 is a state in which the bridge table 131 has disappeared or a state in which the bridge function is OFF.

(Step S11) The transmission / reception unit 115 receives the LCP Echo Request packet from the BAS 200. Further, the transmission / reception unit 115 receives the LCP Echo Request packet from the client device 300.
(Step S12) The data acquisition unit 113 stores the information registered in the source MAC address, the destination MAC address, and the session ID of the LCP Echo Request packet transmitted by the BAS 200 in the storage unit 150. Further, the data acquisition unit 113 stores the information registered in the source MAC address, the destination MAC address, and the session ID of the LCP Echo Request packet transmitted by the client device 300 in the storage unit 150.

(Step S13) The end determination unit 116 compares the destination MAC address included in the LCP Echo Request packet received from the BAS200 with the MAC address registered in the MAC address table 141.

(Step S14) The end determination unit 116 determines whether or not the destination MAC address included in the LCP Echo Request packet received from the BAS 200 matches the MAC address registered in the MAC address table 141. If they match (Yes in step S14), the end determination unit 116 advances the process to step S15.
If they do not match (No in step S14), the end determination unit 116 discards the information stored in the storage unit 150. Then, the end determination unit 116 ends the process.

In this way, the end determination unit 116 controls not to transmit the PADT packet to the BAS 200 when they do not match (No in step S14). That is, the end determination unit 116 controls not to instruct the BAS 200 to end the session.

(Step S15) The packet generation unit 114 generates a first PADT packet and a second PADT packet.
(Step S16) The transmission / reception unit 115 transmits the first PADT packet to the BAS200. The transmission / reception unit 115 transmits the second PADT packet to the client device 300.

(Step S17) The transmission / reception unit 115 receives the PADT packet from the BAS 200. Further, the transmission / reception unit 115 receives the PADT packet from the client device 300.
(Step S18) Whether or not the session ID included in the first and second PADT packets and the session ID included in the PADT packet received from the BAS 200 and the client device 300 are the same in the end determination unit 116. Is determined. If they are the same, the end determination unit 116 detects that the session has ended in the BAS 200 and the client device 300.
If the end determination units 116 are not the same, the process may proceed to step S15. Alternatively, the end determination unit 116 may end the process if they are not the same.

In this way, the control unit 110 receives the LCP Echo Request packet from the BAS 200 when the bridge function is stopped (step S11). The control unit 110 determines whether or not the destination MAC address included in the LCP Echo Request packet and the MAC address registered in the MAC address table 141 match (step S14). When the control unit 110 determines that they do not match (No in step S14), the control unit 110 does not instruct the BAS200 to end the session established by the BAS200 with the client device of the destination MAC address included in the LCP Echo Request packet. Control.

Here, it is assumed that the BAS 200 and the client device 301 have established a session. The BAS200 transmits LCP Echo request packets at regular intervals. The LCP Echo request packet transmitted by the BAS 200 is received by the bridge device 100 due to flooding or the like. The MAC address of the client device 301 is registered in the destination MAC address of the LCP Echo request packet. In step S14, the bridge device 100 determines that the MAC address of the client device 301 and the MAC address of the client device 300 registered in the MAC address table 141 do not match. Therefore, the bridging device 100 does not transmit the PADT packet to the BAS 200. Therefore, the first embodiment can prevent the BAS 200 from erroneously ending the session established by the BAS 200 and the client device 301.

Embodiment 2.
Next, the second embodiment will be described. The matters different from the first embodiment will be mainly described, and the description of the matters common to the first embodiment will be omitted. In the description of the second embodiment, FIGS. 1 to 8, 10 and 11 are referred to.

The first embodiment has described a case where the MAC address of the client device 300 is stored in the storage unit 140 before a power failure or the like occurs. The second embodiment describes a case where the MAC address of the client device 300 is stored in the storage unit 140 at the timing when the bridge function is turned off by the operation of the user.

FIG. 12 is a functional block diagram showing the configuration of the bridge device according to the second embodiment. The bridge device 100a has a bridge function unit 120a. The function of the bridge function unit 120a will be described in detail later.
The configuration of FIG. 12, which is the same as or corresponds to the configuration shown in FIG. 3, has the same reference numerals as those shown in FIG.

FIG. 13 is a sequence diagram showing an example of the session end processing of the second embodiment. For a description of FIG. 13, see FIGS. 1, 4, 7, 8 and 12.
(Step S131) The bridging device 100a is turned on by the user's operation. As a result, the function of the bridge function unit 120a of the bridge device 100a becomes effective.

(Step S132) The client device 300 transmits a PADI packet to the bridge device 100a in order to establish a session with the BAS 200.
(Step S133) The bridge function unit 120a of the bridge device 100a acquires the MAC address of the client device 300 from the PADI packet. The bridge function unit 120a of the bridge device 100a creates a bridge table 131. The bridge function unit 120a of the bridge device 100a registers the MAC address of the client device 300 in the item of the client device of the bridge table 131.

(Step S134) The transmission / reception unit 115 of the bridge device 100a transmits a PADI packet to the BAS200.
(Step S135) The BAS 200 and the client device 300 perform PPPoE authentication via the bridge device 100a. As a result, a session is established between the BAS 200 and the client device 300.
The bridge function unit 120a of the bridge device 100a registers the session ID in the session ID item of the bridge table 131. The bridge function unit 120a of the bridge device 100a registers the MAC address of the BAS 200 in the BAS item of the bridge table 131.

(Step S136) The bridge device 100a receives an instruction to turn off the bridge function by a user operation. That is, the bridge function unit 120a of the bridge device 100a receives an instruction to stop the bridge function. Then, the bridge function unit 120a of the bridge device 100a executes preparations for disabling the bridge function.
(Step S137) The bridge function unit 120a of the bridge device 100a registers the information registered in the item of the bridge table 131 in the MAC address table 141. For example, the bridge function unit 120a of the bridge device 100a registers the MAC address of the client device 300 registered in the bridge table 131 in the MAC address table 141. Then, the bridge function unit 120a of the bridge device 100a shifts to the invalid state of the bridge function.
As described above, in the bridge device 100, even if the bridge function shifts to the OFF state, the power supply of the bridge device 100 remains ON.

Here, in the first embodiment, it has been described that the storage unit 140 is realized by the non-volatile storage device 103 in order to prevent the MAC address table 141 from being lost due to the influence of a power failure or the like. However, in the second embodiment, since the MAC address table 141 is not lost and the period for holding the MAC address table 141 may be short, the storage unit 140 may be realized by the volatile storage device 102.

Since the processing after step S137 is the same as that of steps S111 to 121, the description thereof will be omitted.
In this way, the bridge device 100a stores the MAC address of the client device 300 in the storage unit 140 at the timing when the bridge function is turned off. As a result, the bridge device 100a can determine step S14. Therefore, for example, when the bridge device 100a receives the LCP Echo request packet addressed to the client device 301 from the BAS200, the bridge device 100a does not transmit the PADT packet to the BAS200. Therefore, the second embodiment can prevent the BAS 200 from erroneously ending the session.

Embodiment 3.
Next, the third embodiment will be described. The matters different from the first embodiment will be mainly described, and the description of the matters common to the first embodiment will be omitted. In the description of the third embodiment, FIGS. 1 to 8, 10 and 11 are referred to.

The second embodiment describes a case where the MAC address of the client device 300 is stored in the storage unit 140 at the timing when the bridge function is turned off by the operation of the user. The third embodiment describes the case where the MAC address of the client device 300 is stored in the storage unit 140 at an arbitrary timing.

FIG. 14 is a functional block diagram showing the configuration of the bridge device according to the third embodiment. The bridge device 100b has a control unit 110b and a bridge function unit 120b. The control unit 110b has a packet generation unit 114b. The packet generation unit 114b generates an ARP (Address Resolution Protocol) packet. The functions of the packet generation unit 114b and the bridge function unit 120b will be described in detail later.
The configuration of FIG. 14, which is the same as or corresponds to the configuration shown in FIG. 3, has the same reference numerals as those shown in FIG.

FIG. 15 is a diagram showing the format of the ARP packet. The ARP packet format 604 includes a target IP (Internet Protocol) address, a source IP address, a source MAC address, and a destination MAC address.

FIG. 16 is a sequence diagram showing an example of the session end processing of the third embodiment. For a description of FIG. 16, see FIGS. 1, 4, 7, 8, 14, and 15.
(Step S141) The bridging device 100b is turned on by the user's operation. As a result, the function of the bridge function unit 120b of the bridge device 100b becomes effective.

(Step S142) The bridge function unit 120b of the bridge device 100b searches for the MAC address of the client device to which the bridge device 100b is connected. Here, the bridge function unit 120b of the bridge device 100b may perform the search at an arbitrary timing by the operation of the user. Further, the bridge function unit 120b of the bridge device 100b may periodically perform the search.

The bridge function unit 120b of the bridge device 100b instructs the packet generation unit 114b to generate an ARP packet. The packet generation unit 114b of the bridging device 100b generates an ARP packet. This will be described in detail. The packet generation unit 114b of the bridge device 100b registers the IP address assigned to the client device to be searched as the target IP address of the ARP packet. The packet generation unit 114b of the bridge device 100b registers the IP address assigned to the bridge device 100b as the source IP address of the ARP packet. The packet generation unit 114b of the bridge device 100b registers the MAC address of the bridge device 100b in the source MAC address of the ARP packet. The packet generation unit 114b of the bridge device 100b registers "FF: FF: FF: FF: FF: FF" in the destination MAC address of the ARP packet. By registering "FF: FF: FF: FF: FF: FF" in the destination MAC address, the ARP packet is transmitted by broadcasting.
The ARP packet is information instructing the transmission of the MAC address.

(Step S143) The bridge function unit 120b of the bridge device 100b transmits an ARP packet. That is, the bridge function unit 120b of the bridge device 100b instructs the client device 300 to transmit the MAC address of the client device 300.
(Step S144) The client device 300 receives the ARP packet. When the target IP address of the ARP packet and the IP address assigned to the client device 300 match, the client device 300 transmits the response of the ARP packet to the bridge device 100b. The response of the ARP packet includes the MAC address of the client device 300.

(Step S145) The bridge function unit 120b of the bridge device 100b registers the MAC address of the client device 300 included in the response of the ARP packet in the MAC address table 141.
(Step S146) The client device 300 transmits a PADI packet to the bridge device 100b in order to establish a session with the BAS 200.

(Step S147) The bridge function unit 120b of the bridge device 100b acquires the MAC address of the client device 300 from the PADI packet. The bridge function unit 120b of the bridge device 100b creates a bridge table 131. The bridge function unit 120b of the bridge device 100b registers the MAC address of the client device 300 in the item of the client device of the bridge table 131.

(Step S148) The transmission / reception unit 115 of the bridge device 100b transmits a PADI packet to the BAS200.
(Step S149) The BAS 200 and the client device 300 perform PPPoE authentication via the bridge device 100. As a result, a session is established between the BAS 200 and the client device 300.

The bridge function unit 120b of the bridge device 100b registers the session ID in the session ID item of the bridge table 131. The bridge function unit 120b of the bridge device 100b registers the MAC address of the BAS 200 in the BAS item of the bridge table 131.

(Step S150) A power failure occurs. Further, step S150 may be considered as a case where the bridge function is turned off by the operation of the user.
(Step S151) The bridge device 100b is restarted.
Since the processing after step S151 is the same as that of steps S111 to 121, the description thereof will be omitted.

In this way, the bridge device 100b stores the MAC address of the client device 300 in the storage unit 140 at an arbitrary timing. As a result, the bridge device 100b can determine step S14. Therefore, for example, when the bridge device 100b receives the LCP Echo request packet addressed to the client device 301 from the BAS200, the bridge device 100b does not transmit the PADT packet to the BAS200. Therefore, the third embodiment can prevent the BAS 200 from erroneously ending the session.

The features of each of the embodiments described above can be combined with each other as appropriate.

10 Optical network, 20,21,22 network, 100,100a, 100b, 500 bridge device, 110,110b control unit, 111 packet monitoring unit, 112 packet identification unit, 113 data acquisition unit, 114,114b packet generation unit, 115 Transmission / reception unit, 116 end judgment unit, 120, 120a, 120b bridge function unit, 130 table storage unit, 131 bridge table, 140 storage unit, 141 MAC address table, 150 storage unit, 160 WAN port, 170 LAN port, 200 BAS , 300,301,302,303 client device, 400 ISP.

Claims (10)

It is a relay device that relays information transmitted and received between the first client device and the information processing device by having a bridge function.
A storage unit that stores the first information, which is information for identifying the first client device,
Information for confirming the connection with the second client device, which is one of the plurality of client devices including the first client device, when the bridge function is stopped. Connection confirmation information including the second information, which is information for identifying the second client device, is received from the information processing device, and it is determined whether or not the first information and the second information match. If it is determined that they do not match, the control unit that controls not to instruct the information processing device to end the session established by the second client device and the information processing device.
A relay device having. The control unit determines whether or not the first information and the second information match, and if it determines that they match, the session established by the second client device and the information processing device. Instruct the information processing apparatus to end the
The relay device according to claim 1. The control unit determines whether or not the first information and the second information match, and if it determines that they match, the session established by the second client device and the information processing device. Instruct the second client device to end the process.
The relay device according to claim 1 or 2. The first information included in the information transmitted by the first client device or the information processing device is stored in the storage until the session is established between the first client device and the information processing device. It also has a bridge function unit to be stored in the unit.
The relay device according to any one of claims 1 to 3. The bridge function unit stores the first information included in the information for searching for the information processing device transmitted by the first client device in the storage unit.
The relay device according to claim 4. When the stop instruction of the bridge function is received, the bridge function unit further includes the first information registered in the bridge information which is the information used when executing the relay, and stores the first information in the storage unit.
The relay device according to any one of claims 1 to 3. It further has a bridge function unit that instructs the first client device to transmit the first information and stores the first information included in the response from the first client device in the storage unit. ,
The relay device according to any one of claims 1 to 3. The first information is a physical address that identifies the first client device.
The second information is a physical address that identifies the second client device.
The relay device according to any one of claims 1 to 7. By having a bridge function, a relay device that relays information transmitted and received between the first client device and the information processing device can be used.
Information for confirming the connection with the second client device, which is one of the plurality of client devices including the first client device, when the bridge function is stopped. Connection confirmation information including the second information, which is information for identifying the second client device, is received from the information processing device, and the connection confirmation information is received.
It is determined whether or not the first information, which is the information for identifying the first client device stored in the storage unit, and the second information match.
If it is determined that they do not match, the information processing device is controlled so as not to instruct the end of the session established by the second client device and the information processing device.
End judgment method. By having a bridge function, a relay device that relays information transmitted and received between the first client device and the information processing device can be used.
Information for confirming the connection with the second client device, which is one of the plurality of client devices including the first client device, when the bridge function is stopped. Connection confirmation information including the second information, which is information for identifying the second client device, is received from the information processing device, and the connection confirmation information is received.
It is determined whether or not the first information, which is the information for identifying the first client device stored in the storage unit, and the second information match.
If it is determined that they do not match, the information processing device is controlled so as not to instruct the end of the session established by the second client device and the information processing device.
An end judgment program that executes processing.

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