JP4796413B2 - Network equipment - Google Patents

Description

  The present invention relates to a network device capable of performing various operations according to a LifeTime value of an IPv6 (Internet Protocol version 6) address acquired from a router.

  One feature of IPv6 is that addresses can be automatically set, and addresses can be created by router advertisements (RA) transmitted from routers. That is, an IPv6 address is generated from the Prefix information included in the RA and the Mac (Media access control) address of the own device. This address is called a stateless address. The Stateless address has LifeTime, and this information is included in the RA as a Valid LifeTime (valid period) and a Preferred LifeTime (referenceable period).

On the other hand, in Patent Document 1, in order to prevent personal information from being acquired based on an IP address obtained by eavesdropping on communication and invasion of privacy, a plurality of effective IP addresses are held. A network system, a router, a host, a prefix management method, and an IP address management method are disclosed in which an IP address to be used as a source address of its own node is selected.
JP 2003-198582 A "Network System, Router, Host, Prefix Management Method and IP Address Management Method"

  As described above, the address is automatically set in IPv6, but when the valid life time expires, the router disables the IP address. For example, the valid life time is being transmitted while transmitting a large amount of data. When the period expires, the communication is interrupted and the data cannot be transmitted to the end.

  In addition, other processing that is desired to be performed in association with the LifeTime value of the IPv6 address can be considered, but there has been no mechanism that can meet such needs.

  On the other hand, in Patent Literature 1, the provider side is requested to assign a new second type prefix before all the second type prefixes become invalid. It is intended to hold a plurality of effective IP addresses, and does not attempt to avoid the adverse effects caused by the expiration of LifeTime during communication as described above. This is because Patent Document 1 aims to prevent infringement of privacy using an IP address.

  The present invention has been proposed in view of the above-described conventional problems, and an object of the present invention is to provide a network device capable of performing various operations according to the LifeTime value of the IPv6 address acquired from the router. Is to provide.

In order to solve the above-described problem, in the present invention, as described in claim 1 , communication is performed when the LifeTime value included in the prefix that is connected to the network and is the source of the address generation expires. a network device disconnection Ru performed, LifeTime value included in the prefix information distributed from the router determines whether it is appropriate, means for generating an address based on the prefix where appropriate, transmission system action At the start of the check, confirm that the LifeTime value of the address being used has expired when a line disconnection is detected during communication and means for selecting the source address at the time of transmission from the available addresses. , Clear the session, resend using a new address, or create a new address The network device and means for performing notification processing are the gist.

Further, as described in claim 2, in the network device according to claim 1 can comprise means for setting the correspondence between the operation and the upper Symbol LifeTime Value.

Further, as described in claims 3 and 4 , it can be configured as an operation control method for a network device.

  In the network device of the present invention, various operations can be performed according to the LifeTime value of the IPv6 address acquired from the router, and appropriate measures can be taken according to the situation.

  Hereinafter, preferred embodiments of the present invention will be described.

<Configuration>
FIG. 1 is an overall configuration diagram showing an embodiment of a network system to which a network device of the present invention is applied.

  In FIG. 1, network devices 1A and 1B to which the present invention is applied are connected to a network 6 together with routers 2A and 2B that distribute IPv6 prefixes and other PCs (Personal Computers) 3A to 3C.

  FIG. 2 is a diagram illustrating a hardware configuration example when the network device 1 is an image processing apparatus.

  In FIG. 2, the network device 1 includes a controller 101, an operation panel 121, an FCU (Facsimile Control Unit) 122, and an engine unit 123.

  The controller 101 includes a CPU (Central Processing Unit) 102, a system memory 103, an NB (North Bridge) 104, an SB (South Bridge) 105, an ASIC (Application Specific Integrated Circuit) 106, a local memory 107, and an HDD (Hard Disk Drive) 108. , Flash ROM (Flash Read Only Memory) 109, NVRAM (Non Volatile RAM) 110, SDRAM (Synchronous Dynamic Random Access Memory) 111, Secure Device 112, Ethernet (registered trademark) I / F (Ethernet (registered trademark) Interface) 113 USB I / F (Universal Serial Bus Interface) 114, IEEE 1394 I / F (the Institute of Electrical and Electronic Engineers 1394 Interface) 115, Centronics I / F 116, wireless I / F 117, and external storage medium I / F 118 .

  The operation panel 121 is connected to the ASIC 106 of the controller 101. The FCU 122 and the engine unit 123 are connected to the ASIC 106 of the controller 101 via a bus 124.

  In the controller 101, a local memory 107, an HDD 108, a flash ROM 109, an NVRAM 110, an SDRAM 111, a secure device 112, and the like are connected to the ASIC 106, and the CPU 102 and the ASIC 106 are connected via the NB 104 of the CPU chip set. The controller 101 corresponds to the case where the interface of the CPU 102 is not disclosed by connecting the CPU 102 and the ASIC 106 via the NB 104.

  The ASIC 106 and the NB 104 are connected via an AGP (Accelerated Graphics Port) 119. In a software configuration to be described later, in order to control execution of one or more processes forming an application and a platform, the ASIC 106 and the NB 104 are connected via an AGP 119 instead of a low-speed bus, thereby preventing a decrease in performance.

  The CPU 102 performs overall control by software.

  The NB 104 includes a CPU 102, a system memory 103, an SB 105, an ASIC 106, an Ethernet (registered trademark) I / F 113, a USB I / F 114, an IEEE 1394 I / F 115, a Centronics I / F 116, a wireless I / F 117, and an I / F 118 for an external storage medium. It is a bridge for connecting.

  The SB 105, Ethernet (registered trademark) I / F 113, USB I / F 114, IEEE 1394 I / F 115, Centronics I / F 116, wireless I / F 117, and external storage medium I / F 118 are connected to the NB 104 via the bus 120. ing. Note that the SB 105 is a bridge for connecting the bus 120 to a ROM, a peripheral device, or the like.

  The system memory 103 is a memory used as a drawing memory of the image processing apparatus. The local memory 107 is a memory used as an image buffer and a code buffer.

  The ASIC 106 is an IC for image processing applications having hardware elements for image processing. The HDD 108 is an example of storage (auxiliary storage device) that stores image data, document data, programs, font data, forms, and the like.

  The Ethernet (registered trademark) I / F 113 is an interface device that connects the image processing apparatus to a network. The USB I / F 114, the IEEE 1394 I / F 115, the Centronics I / F 116, and the wireless I / F 117 are interfaces conforming to the respective standards, and may be connected to a network.

  The flash ROM 109 is a memory in which programs and data can be written from the outside. NVRAM 110 and SDRAM 111 are memories that retain information even when the power is off.

  The external storage medium I / F 118 is detachable from the external storage medium, and is an interface conforming to the standard of the external storage medium. For example, an SD (Secure Digital) card, a compact flash (registered trademark), a ROM-DIMM (Dual In-line Memory Module) or the like is used as an external storage medium.

  The secure device 112 is a device that cannot be used again once physically removed, and stores key information.

  The operation panel 121 is an operation unit that accepts an input operation from an operator and performs display for the operator. The FCU 122 has a memory and is used to temporarily store facsimile data received when the power is OFF.

  Depending on the configuration of the image processing apparatus, there are a Flash ROM 109, an SDRAM 111, a secure device 112, a USB I / F 114, an IEEE 1394 I / F 115, a Centronics I / F 116, a wireless I / F 117, an external storage medium I / F 118, and an FCU 122. Sometimes it doesn't.

  FIG. 3 is a diagram illustrating a software configuration example when the network device 1 is an image processing apparatus.

  In FIG. 3, the software is roughly composed of an application unit 131 and a platform unit 138. Here, the description of the OS (Operating System) part (kernel) is omitted.

  The application unit 131 performs processing unique to user services related to image forming processing such as copying, faxing, scanners, and printers. The application unit 131 includes a copy application 132 that is a copy application, a fax application 133 that is a facsimile application, a scanner application 134 that is a scanner application, a net file application 135 that is a network file application, and a page description. A printer application 136 which is an application for language and printer.

  The platform unit 138 includes various control units that interpret processing requests from the application unit 131 and generate acquisition requests for various resources such as hardware. The platform unit 138 includes a system control unit 139, a memory control unit 140, a network control unit 141, an engine control unit 142, a security control unit 143, an operation control unit 144, and a fax control unit 145. The platform unit 138 is configured to have an API (Application Program Interface) 137 that can receive a processing request from the application unit 131 using a predefined function.

  The system control unit 139 performs processing such as application management, operation unit control, system screen display, LED display, hardware resource management, and interrupt application control.

  The memory control unit 140 performs memory control such as acquisition and release of memory and compression and decompression of image data.

  The engine control unit 142 controls an engine of hardware resources (not shown).

  The fax control unit 145 is connected to a GSTN (General Switched Telephone Network) I / F, transmits / receives a facsimile using a PSTN (Public Switched Telephone Network) or an ISDN (Integrated Services Digital Network) network from each application layer of the system controller, and backs up. Provides an API for registering / quoting various facsimile data managed in the memory for use, facsimile reading, facsimile reception printing, and the like.

  The operation control unit 144 controls an operation panel serving as information transmission means between the operator and the main body control.

  The network control unit 141 is connected to a network such as Ethernet (registered trademark), provides a service that can be commonly used for applications that require network I / O (Input Output), and receives from each side of the network by each protocol. The distributed data is distributed to each application, and mediation is performed when data from each application is transmitted to the network side.

  The security control unit 143 provides a security service to the application unit 131.

  The HDD 108 stores data for operating each application and each control unit, and stores image data.

  The NVRAM 110 stores setting information.

  The CPU 102 (FIG. 2) controls the entire image processing apparatus, executes each control unit of the platform unit 138, and executes each application of the application unit 131 that uses them.

  Depending on the configuration of the image processing apparatus, some applications of the application unit 131 and some control units of the platform unit 138 may not exist.

  FIG. 4 is a diagram illustrating a configuration example of the network control unit 141.

  In FIG. 4, a main processing unit 156 is a central part of the network control unit 141, and controls and supervises other processing units.

  The IPv6 environment processing unit 153 sets an IPv6 address for the kernel and controls the IPv6 management table. The IPv6 address management table unit 154 is data having an IPv6 address in operation.

  The router advertisement / request processing unit 157 transmits and receives router advertisement (RA) and router solicitation (RS), and the neighbor advertisement / request processing unit 158 includes a neighbor advertisement (NA) and a neighbor request (NS). This is the part that transmits and receives Solicitation.

  The upper protocol processing unit 155 includes a number of protocols (SMTP (Simple Mail Transfer Protocol), port 9100, SNMP (Simple Network Management Protocol), DNS (Domain Name System), etc. on TCP (Transmission Control Protocol) and UDP (User Datagram Protocol). ) Is the part that performs the control.

  The other control unit communication unit 151 is a part that communicates with other control services and the application unit 131 (FIG. 3). The unique application processing unit 152 is a part that performs an action in the present invention. The network protocol stack 159 below the socket is a kernel part, and performs low-layer control of the network such as socket, TCP, and UDP.

  FIG. 5 is a diagram showing an example of the IPv6 address management table unit 154, which is an IPv6 address and LifeTime management table.

  A table T1 that holds the expiration time of the Valid LifeTime and the Preferred LifeTime acquired by the RA for each IPv6 address, a table T2 that holds information about whether to control the Valid LifeTime or the Preferred LifeTime for each IPv6 address, and IPv6. For each address, there are provided tables T3 and T4 for holding a value of Valid LifeTime or Preferred LifeTime and corresponding operations. Note that the operations in the tables T3 and T4 can include preconditions for starting the operations (for example, when communication is disconnected).

<General operation>
FIG. 6 is a diagram illustrating how the router multicasts router advertisement (RA).

  In FIG. 6, routers 2A and 2B multicast router advertisements respectively. Unlike broadcast in IPv4, multicast is used for transmission to multiple destinations in IPv6. This eliminates the need to process multicasts that are not addressed to you.

  FIG. 7 is a diagram illustrating a state in which a network device multicasts a router request (RS).

  In FIG. 7, the network device 1A multicasts a router request to the routers 2A and 2B. In this case, normally, the network device 1B and the PCs 3A to 3C do not process the RS.

  FIG. 8 is a diagram illustrating a state in which the network device multicasts the Neighbor Solicitation (NS).

  In FIG. 8, the network device 1A multicasts the neighborhood request. Since NS is used for IPv6 address duplication check, all nodes receive it.

  FIG. 9 is a sequence diagram for determining an IPv6 Stateless address.

  In FIG. 9, the router sends a router advertisement (RA) (step S1), and when the network device receives the router advertisement (RA) from the router, it generates an IPv6 Stateless address from the RA prefix information and its own Mac address. (Step S2). Then, a neighbor request (NS) is transmitted (step S3), and if there is no neighbor advertisement (NA) for a certain period of time, the address is determined (step S4).

  FIG. 10 is a sequence diagram for determining an IPv6 Stateless address when a network device issues a router solicitation (RS) itself.

  In FIG. 10, the network device sends a router request (RS) to the router (step S11). The router that has received the RS sends a router advertisement (RA) (step S12). Upon receiving the router advertisement (RA) from the router, the network device generates an IPv6 Stateless address from the RA prefix information and its own Mac address (step S13). Then, a neighbor request (NS) is transmitted (step S14), and if there is no neighbor advertisement (NA) for a certain period of time, the address is determined (step S15).

  FIG. 11 is a diagram showing the format of the RA packet. The IPv6 header, router advertisement (RA), and prefix information are arranged next to the Ethernet (registered trademark) header.

  FIG. 12 is a diagram showing the format of the IPv6 header, which includes version, traffic class, flow label, payload length, next header, maximum hop count, source address, and destination address.

  FIG. 13 is a diagram showing the format of router advertisement (RA), which includes type, code, checksum, current maximum hop count, M, O, reserved area, router valid period, reachable period, retransmission timer, and options. It is.

  FIG. 14 is a diagram showing the format of prefix information, which includes type, data length, prefix length, L, A, reserved area, valid period, referable period, reserved area, and prefix. The valid period corresponds to Valid LifeTime, and the referable period corresponds to Preferred LifeTime.

  FIG. 15 is a diagram showing the format of an RS packet. An IPv6 header and a router request (RS) are arranged next to the Ethernet (registered trademark) header. The format of the IPv6 header is as shown in FIG.

  FIG. 16 is a diagram showing a format of a router solicitation (RS), which includes a type, a code, a checksum, a reserved area, and options.

  FIG. 17 is a diagram showing the format of the NS packet. The IPv6 header and the neighbor request (NS) are arranged next to the Ethernet (registered trademark) header. The format of the IPv6 header is as shown in FIG.

  FIG. 18 is a diagram showing the format of the Neighbor Solicitation (NS), which includes type, code, checksum, reserved area, target address, and options.

  FIG. 19 is a diagram showing the format of the NA packet. The IPv6 header and the neighborhood advertisement (NA) are arranged next to the Ethernet (registered trademark) header. The format of the IPv6 header is as shown in FIG.

  FIG. 20 is a diagram showing the format of the neighborhood advertisement (NA), which includes type, code, checksum, R, S, O, reserved area, target address, and option.

<Process until the Stateless address is confirmed>
FIG. 21 is a flowchart showing an example of processing up to the stateless address determination.

  In FIG. 21, the process is started (step S101). After receiving the RA (step S102), if an appropriate LifeTime value is received (Yes in step S103), the RA prefix and its own Mac address are used. A Stateless address is generated (step S104).

  Next, after the NS transmission for duplication confirmation (step S105), if no NA is received after a certain time (No in step S106), the address is fixed (step S107), and the management table (table T1 in FIG. 5) Is registered (step S108).

  When the LifeTime value is not appropriate (No in Step S103), when NA is received within a certain time (Yes in Step S106), or in other cases, another address is used as necessary (Step S109). The process is terminated (step S110). For example, when there is a disadvantage that the value of LifeTime is small for long-time communication (transmission of a large size document), the received RA is not used, but an RA having a prefix that stores another long LifeTime is used. Use link local address or manually set address.

  FIG. 22 is a diagram illustrating an operation example in the network control unit 141 until the Stateless address is determined.

  In FIG. 22, after receiving the RA by the router advertisement / request processing unit 157 (steps S111 and S112), the main processing unit 156 checks the LifeTime and generates the Stateless address, and transmits the NS by the neighborhood advertisement / request processing unit 158. (Steps S113 and S114).

  If the NA is not received after a certain time, it is determined that the addresses are not duplicated, and the main processing unit 156 sets the address in the network protocol stack 159 below the socket of the kernel unit through the IPv6 environment processing unit 153 (steps S115 and S116). ), Information is accumulated in the IPv6 address management table unit 154 (step S117).

  FIG. 23 is a diagram illustrating an operation example in the network control unit 141 until the stateless address is determined when the network device issues a router request (RS) by itself.

  In FIG. 23, the router advertisement / request processing unit 157 receives the RA after the RS transmission (step S110) (steps S111 and S112). The subsequent processing (steps S113 to S117) is the same as that in FIG.

<Setting of operation control by LifeTime value>
FIG. 24 is a diagram illustrating an example of a setting screen for operation control based on the LifeTime value, which is an example of a screen displayed when remote access is performed using an operation panel of a network device or a PC. The operation is “address generation” as an example.

  In FIG. 24, there are a switch for controlling generation, a switch for controlling each LifeTime, an input field for the value, and the like.

  FIG. 25 is a diagram illustrating an operation example in the network control unit 141 when setting operation control based on the LifeTime value.

  In FIG. 25, when receiving a request from the other control unit communication unit 151 (steps S121 and S122), the main processing unit 156 stores the requested content in the NVRAM 110 or the like (step S123), and simultaneously via the IPv6 environment processing unit 153. Then, data is registered in the management table (tables T2 to T4 in FIG. 5) of the IPv6 address management table unit 154 (steps S124 and S125).

<Processing when sending actions>
FIG. 26 is a flowchart showing an example of processing at the time of transmission system action, in which an IPv6 source address is appropriately selected at the time of transmission system action.

  In FIG. 26, processing is started (step S131), and when a transmission action occurs (step S132), an IPv6 address registered from the management table is selected (step S133). As a reference at this time, the longest Valid LifeTime or Preferred LifeTime is automatically selected, the user makes a selection, or the link local address is selected if the other party is in the same subnet.

  Then, the selected source address is set (step S134), actual transmission is performed (step S135), and the process is terminated (step S136).

  FIG. 27 is a diagram illustrating an operation example in the network control unit 141 at the time of transmission system action.

  In FIG. 27, when receiving a request from the other control unit communication unit 151 (steps S141 and S142), the main processing unit 156 selects an appropriate IPv6 address from the IPv6 environment processing unit 153 and the IPv6 address management table unit 154 (step S143). To S146), transmission is performed via the upper protocol processing unit 155 using the protocol specified in the request (steps S147 and S148).

<Processing when LifeTime reaches a specific value>
FIG. 28 is a flowchart illustrating a processing example when LifeTime becomes a specific value.

  In FIG. 28, when the process is started (step S151), it is determined whether LifeTime has reached a preset specific value (step S152), and a corresponding action is executed if applicable (step S153). Then, sleep is performed for a predetermined time (step S154), and the process returns to the determination of LifeTime (step S152).

  For example, when the Preferred LifeTime or Valid LifeTime expires, the router request (RS) is expected to be received and the RA is expected to be received, or the registered management PC or management device is notified by e-mail or SNMP. It is possible to send a Trap to alert, or use a specific address such as Linklocal, manual setting, or IPv4 address thereafter.

  FIG. 29 is a diagram illustrating an operation example in the network control unit 141 in a case where a mail notification is performed when LifeTime becomes a specific value.

  In FIG. 29, the main processing unit 156 periodically monitors the Expire information of the LifeTime of the IPv6 address registered in the IPv6 address management table unit 154 (steps S161 to S164), the unique application processing unit 152, the higher-level protocol processing unit. The mail is sent to the outside through (in this case SMTP) 155 (steps S165 to S168).

  FIG. 30 is a diagram illustrating an operation example in the network control unit 141 when RS transmission is performed when LifeTime reaches a specific value.

  In FIG. 30, the main processing unit 156 periodically monitors the Expire information of the LifeTime of the IPv6 address registered in the IPv6 address management table unit 154 (steps S171 to S174), the unique application processing unit 152, the router advertisement / request. The RS is transmitted through the processing unit 157 (steps S175 to S178).

<Processing when Valid LifeTime expires during session>
FIG. 31 is a flowchart illustrating a processing example when Valid LifeTime expires during a session.

  In FIG. 31, processing is started (step S181), communication is in progress (step S182), and when the communicating application detects a line disconnection (step S183), the Valid LifeTime of the used address is checked and Expire. It is confirmed (step S184), and session clear processing (socket release, memory release, etc.) is performed (step S185).

  Thereafter, a predetermined action (retransmission, notification of a new address to the previous communication partner, etc.) is performed (step S186), and the process ends (step S187).

  FIG. 32 is a diagram illustrating an operation example in the network control unit 141 when Valid LifeTime expires during a session.

  In FIG. 32, when the communication is disconnected, the upper protocol processing unit 155 accesses the network protocol stack 159 below the kernel socket and confirms that the Valid LifeTime is Expire (steps S191 and S192).

  The main processing unit 156 updates the information in the management table unit (steps S193 to S197), and notifies the upper application through the unique application processing unit 152, the upper protocol processing unit 155, and the other control unit communication unit 151 (steps S198 to S198). S201), retransmission is performed as necessary (steps S202 and S203).

<Summary>
As described above, the present invention describes how the network device behaves according to the value of LifeTime. For example, the management device is notified when LifeTime becomes a specific value, or a predetermined operation is performed when disconnected during communication. Therefore, it is possible to take an appropriate response according to the situation.

  Further, by selecting RA itself according to the value of LifeTime in RA (such as not using an address with a short LifeTime), it is possible to select an IPv6 address appropriate for the application or user.

  In addition, by making it possible to set in advance whether the address can be used, the user can control the IPv6 address based on the value of LifeTime.

  In addition, since the source address can be properly used according to the value of LifeTime, communication using an appropriate IPv6 address can be performed for an application or a user.

  In addition, when the value of LifeTime becomes a specific value, an additional service can be provided to an application or a user by performing an action related to the network.

  In addition, when the value of LifeTime expires, an application or user can continue communication by using another specific address.

  In addition, when the value of LifeTime expires during data communication, recommunication can be performed by safely terminating communication.

  The present invention has been described above by the preferred embodiments of the present invention. While the invention has been described with reference to specific embodiments, various modifications and changes may be made to the embodiments without departing from the broad spirit and scope of the invention as defined in the claims. Obviously you can. In other words, the present invention should not be construed as being limited by the details of the specific examples and the accompanying drawings.

1 is an overall configuration diagram showing an embodiment of a network system to which a network device of the present invention is applied. FIG. 2 is a diagram illustrating an example of a hardware configuration when a network device is an image processing apparatus. FIG. 3 is a diagram illustrating an example of a software configuration when a network device is an image processing apparatus. It is a figure which shows the structural example of a network control part. It is a figure which shows the example of the IPv6 address management table part. It is a figure which shows a mode that a router multicasts a router advertisement (RA). It is a figure which shows a mode that a network device multicasts a router request | requirement (RS). It is a figure which shows a mode that a network device multicasts a neighbor request | requirement (NS). It is a sequence diagram of IPv6 Stateless address determination. It is a sequence diagram of IPv6 Stateless address determination when a network device issues a router solicitation (RS) by itself. It is a figure which shows the format of RA packet. It is a figure which shows the format of an IPv6 header. It is a figure which shows the format of a router advertisement (RA). It is a figure which shows the format of prefix information. It is a figure which shows the format of RS packet. It is a figure which shows the format of a router request | requirement (RS). It is a figure which shows the format of NS packet. It is a figure which shows the format of a neighbor request | requirement (NS). It is a figure which shows the format of NA packet. It is a figure which shows the format of a neighborhood advertisement (NA). It is a flowchart which shows the process example until Stateless address confirmation. It is a figure which shows the operation example in the network control part until a Stateless address decision. It is a figure which shows the operation example in a network control part until a Stateless address decision when a network apparatus issues a router request | requirement (RS) itself. It is a figure which shows the example of the setting screen of the operation control by LifeTime value. It is a figure which shows the operation example in the network control part when setting the operation control by LifeTime value. It is a flowchart which shows the process example at the time of a transmission type | system | group action. It is a figure which shows the operation example in the network control part at the time of transmission type | system | group action. It is a flowchart which shows the process example when LifeTime becomes a specific value. It is a figure which shows the operation example in a network control part in, when mail notification is performed when LifeTime becomes a specific value. It is a figure which shows the operation example in a network control part in case RS transmission is performed when LifeTime becomes a specific value. It is a flowchart which shows the example of a process when Valid LifeTime expires during a session. It is a figure which shows the operation example in a network control part when Valid LifeTime expires during a session.

Explanation of symbols

1, 1A, 1B Network equipment 2A, 2B Router 3A-3C PC
6 Network 101 Controller 102 CPU
103 System memory 104 NB
105 SB
106 ASIC
107 Local memory 108 HDD
109 Flash ROM
110 NVRAM
111 SDRAM
112 Secure Device 113 Ethernet (Registered Trademark) I / F
114 USB I / F
115 IEEE 1394 I / F
116 Centronics I / F
117 Wireless I / F
118 I / F for external storage media
119 AGP
120 Bus 121 Operation Panel 122 FCU
123 Engine unit 124 Bus 131 Application unit 132 Copy application 133 Fax application 134 Scanner application 135 Net file application 136 Printer application 137 API
138 Platform unit 139 System control unit 140 Memory control unit 141 Network control unit 142 Engine control unit 143 Security control unit 144 Operation control unit 145 Fax control unit 146 Network I / F
151 Other Control Unit Communication Unit 152 Unique Application Processing Unit 153 IPv6 Environment Processing Unit 154 IPv6 Address Management Table Unit 155 Higher Protocol Processing Unit 156 Main Processing Unit 157 Router Advertisement / Request Processing Unit 158 Neighbor Advertisement / Request Processing Unit 159 Network Protocol Below Socket Stack T1-T4 table

Claims (4)

Is connected to a network, a network device that disconnection of the communication is Ru performed when LifeTime value included in prefix is the source address generator has expired,
Means for determining whether the LifeTime value included in the prefix information distributed from the router is appropriate, and generating an address based on the prefix if it is appropriate;
Means for selecting a source address at the time of transmission according to a LifeTime value from available addresses at the start of a transmission action;
Means for confirming that the LifeTime value of the address being used has expired when a line disconnection is detected during communication, performing a session clear process, and performing a retransmission process using a new address or a new address notification process ; A network device characterized by comprising: The network device according to claim 1,
A network device comprising means for setting a correspondence relationship between the LifeTime value and an operation. Is connected to a network, a method of controlling operation network equipment cutting communications Ru performed when LifeTime value included in prefix is the source address generator has expired,
Determining whether the LifeTime value included in the prefix information distributed from the router is appropriate, and generating an address based on the prefix if it is appropriate;
Selecting a source address at the time of transmission according to a LifeTime value from available addresses at the start of a transmission-type action;
A process of confirming that the LifeTime value of the address being used has expired when a line disconnection is detected during communication, performing a session clear process, and performing a retransmission process using a new address or a new address notification process; An operation control method for a network device, comprising: The operation control method for a network device according to claim 3 ,
An operation control method for a network device, comprising a step of setting a correspondence relationship between the LifeTime value and the operation.

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