JP2006093751A - Wan/lan connection automatic control apparatus, wan/lan connection method, and echo server - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a WAN/LAN connection automatic control apparatus whereby an apparatus connected to a WAN or a LAN can be connected to the WAN and the LAN even if a cable is connected to a NIC in any way, WAN functions are provided to the WAN, and LAN functions are provided to the LAN. <P>SOLUTION: A WAN/LAN detection apparatus is provided in an echo server and the automatic control apparatus. In the initial state of the WAN/LAN connection automatic control apparatus, the automatic control apparatus provides only the WAN functions, and then provides the LAN functions when the discrimination of the WAN/LAN is finished, then the WAN/LAN connection automatic control apparatus automatically recognizes the WAN and the LAN and automatically provides the WAN and LAN functions. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a network device connected to a WAN and a LAN.

Hubs and routers are examples of devices that form an IP network that has been rapidly spreading in recent years. If a hub is used, the network cable can be branched. On the other hand, the router has a function of connecting different networks.
When a hub is used, a network having a tree structure can be formed, and the connection form is called a cascade connection. In the Ethernet (registered trademark) cable, a twisted pair cable is generally used, and a cross cable is used when a NIC (Network Interface Card) having two types of cables, straight and cross, is directly connected. When connecting via a hub, a straight cable is used for the hub because the hub is cross-connected internally like a cross cable. On the other hand, in the cascade connection between hubs, the hub has a cross function, so a cross cable must be used. However, since it is troublesome to use two types of cables, straight and cross, the hub itself is generally cascaded. Recognizes connections and functions as a straight for cascaded cables. In other words, a general hub can automatically connect NICs with any configuration using straight cables.

  On the other hand, a router has two or more NICs, transfers data between NICs in the router in response to a transfer request, and outputs data from the NICs. For example, consider a case where there is a router having NIC-A belonging to network A and NIC-B belonging to network B. When a packet to be transferred to network B arrives at NIC-A, the router outputs the same packet from NIC-B. The NICs used at this time are all normally used NICs.

  2. Description of the Related Art A router called a broadband router that has been remarkably popular in recent years connects a WAN (Wide Area Network) and a LAN (Local Area Network). The WAN is usually connected to a provider, and the LAN is usually connected to a network in a home or office. The WAN side is a public network, and it is necessary to prevent intrusion from the outside due to security problems. The LAN side usually provides a DHCP function (Dynamic Host Configuration Protocol). As described above, since the functions provided on the WAN side and the LAN side are different, the home router is created on the premise that the user inserts the cable correctly by dividing the WAN and LAN cable insertion ports in advance.

Takefumi Tomokachi / Yuichi Ikejiri / Tomoaki Kobayakawa “Introduction to Internet Routing” Shosuisha 2001

If the WAN and LAN cables are plugged into the home router in either cable port (= NIC), the user can distinguish which NIC the WAN and LAN cables are plugged into. Must notify the router application.
The problem to be solved is that the user must correctly insert the cable into the WAN and LAN outlets. For the user, there is at least two identical outlets, so there is a good possibility that it will be accidentally inserted. Even if the LAN and WAN are plugged in incorrectly, the router will try to connect to the network that each NIC supports. Normally, both NICs connect to the network as DHCP (Dynamic Host Configuration Protocol) clients. Since WAN providers usually assign addresses by DHCP, NICs that should be on the LAN side are assigned addresses by WAN NICs and can be connected to the WAN.

In such a case, even if a firewall is set on the WAN side, since the firewall is not normally set on the LAN side, the router can freely access from the WAN via the NIC on the LAN side.
Even if a DHCP server is provided on the LAN side, the normal DHCP server first confirms the existence of another DHCP server and operates as a DHCP server only when it does not exist, so it eventually operates as a DHCP client.
Then, for example, if the router is a part of the home server, there is a possibility of being attacked through a security hole, and a mistaken cable insertion may lead to a serious result. Moreover, there is a possibility that a stranger from the WAN can control the home server by a normal procedure, which is not only a server security problem but also a serious safety problem.

SUMMARY OF THE INVENTION An object of the present invention is to automatically recognize a WAN / LAN regardless of how a WAN / LAN cable is inserted and automatically provide necessary functions on both the WAN side and the LAN side.
Another purpose is to set up a firewall as a necessary function on the WAN side.
It is also intended to display a screen that can operate the device with administrator privileges as a necessary function on the LAN side.

In order to solve the above problems, the WAN / LAN connection automatic control apparatus of the present invention includes a network interface, a WAN function providing unit that provides a WAN function, and a LAN function providing unit that provides a LAN function. A switch unit for changing a connection between the network interface and the WAN function providing unit and the LAN function providing unit, and means for detecting the WAN / LAN of the network to which the network interface is connected, the switch unit being a WAN / LAN The network interface is connected to the WAN function providing unit and the LAN function providing unit in conjunction with the means for detecting the error.
A router function is provided between the WAN function providing unit and the LAN function providing unit.

  Further, in the WAN / LAN connection automatic control device of the present invention, after controlling to set the WAN function, and controlling to set the WAN function, the switch unit is controlled to connect to the WAN function, After controlling the switch unit to connect to the WAN function, control to acquire an address via the network interface, and after acquiring the address, send an echo request message to the echo server connected to the network to which the network interface is connected If the echo message is not received, control is performed to set the LAN function, and after setting the LAN function, the switch unit is controlled to connect to the LAN function.

  In the echo server of the present invention, the network interface, the means for receiving the echo request message sent from the WAN / LAN connection automatic control device connected to the network, and the echo message for the echo request message are connected to the WAN / LAN. Means are provided for returning to the automatic control device.

  As a result, the WAN / LAN connection automatic control apparatus according to the present invention automatically recognizes the WAN / LAN regardless of how the user connects the network cable, and provides WAN functions on the WAN side and LAN functions on the LAN side. A LAN function can be provided, and if a firewall is specified for the WAN function, the firewall can be automatically activated, and the WAN / LAN connection automatic control device or a home integrated with the LAN function If a management interface such as a server is designated, a management screen interface can be automatically provided.

  According to the present invention, it is possible to automatically recognize a WAN / LAN regardless of how a user connects a network cable, and to provide a WAN function on the WAN side and a LAN function on the LAN side. .

The objective of automatically recognizing WAN / LAN was realized with minimal procedures and without changing the protocol IP or DHCP.
Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a system configuration diagram showing a device of the present invention, an echo server that is a part of the present invention, a WAN, a LAN, and a DHCP server connected to the device of the present invention. Reference numeral 101 denotes a WAN, which is generally called the Internet. Reference numeral 102 denotes a WAN / LAN connection automatic control apparatus of the present invention. In addition, as a form of this apparatus, a broadband router, a home server with a built-in router function, and the like can be cited. Reference numeral 103 denotes a LAN, which corresponds to, for example, a home network formed by an IP network. Reference numeral 104 denotes a DHCP server that provides an address assignment function and the like to a host existing in the LAN. Note that 104 may be built in 102. Reference numeral 105 denotes an echo server that replies to a message transmitted from 102. Note that the echo server 105 may be directly connected to the LAN 103 instead of the WAN 101. Further, a configuration in which the echo server 105 does not exist may be used.

FIG. 2 is an internal configuration diagram of the automatic connection control apparatus 102 as the apparatus of the present invention. In addition, although 102 is a structure which has two NICs, three or more NICs may be sufficient.
Reference numeral 201 denotes an outer frame of the connection automatic control apparatus 102. A network cable 202 is connected to the WAN 101, and a network cable 203 is connected to the LAN 103. Reference numerals 204 and 205 denote NICs that can receive IP packets from 202 or 203. A WAN / LAN detection device 206 has a function of detecting whether the 204 and 205 are connected to the WAN or the LAN. A packet switch 207 transmits a packet from the WAN 202 to 208 and a packet from the LAN 203 to 209.

  When the WAN / LAN is detected by 206, this switch is fixedly used unless the WAN / LAN is changed. In addition, this switch may be realized by either hardware or software. Reference numeral 208 denotes a WAN function providing unit that provides functions set for the WAN side. Typically, the WAN function provider provides a firewall to prevent unauthorized packets from entering the LAN from the WAN. Reference numeral 209 denotes a LAN function providing unit that provides functions set for the LAN side. Usually, the LAN function providing unit provides a management interface of the apparatus, and allows a user to manage the apparatus via the LAN.

  Reference numeral 210 denotes a router function providing unit. Note that this refers to a device having a function of connecting two networks different from a router and transferring packets between NICs of the router as necessary. The router function of this device is equivalent to the router described above, and provides a function necessary for routing between the WAN and the LAN. When the connection automatic control apparatus is integrated with, for example, a home server, the home server may use the network function of the connection automatic control apparatus. In this case, the home server uses the WAN function providing unit 208 when connecting to the WAN, and the LAN function providing unit 209 when connecting to the LAN. For example, when it is desired to publish a web page to the WAN using an HTTP (Hyper Text Transfer Protocol) server, the HTTP server connects to the network 202 via 208. When the home server wants to distribute a video stream within the LAN, it connects to the network 203 via 209.

  FIG. 3 is a WAN / LAN connection automatic control flowchart when the connection automatic control apparatus and the echo server are installed in the WAN. This flow is executed independently for all NICs. The echo server existing in the WAN is, for example, part of a service provided by a site operated by a business operator or a public organization. When the processing is started, the WAN function is set (301). This step is equivalent to activating the function provided by the WAN function providing unit 208. For example, when the setting is to use the firewall as the WAN function, the operation is to activate the firewall. Next, the switch 207 is switched so that each NIC is connected to the WAN function providing unit (302). When this step is executed, the packet transmitted via 202 and 203 always reaches the WAN function providing unit 208. Next, an address is acquired (303). Details of the address acquisition flow will be described with reference to FIG. When the address acquisition is completed, a message is transmitted to the echo server (304). The message to be transmitted is an address of the connection automatic control device, an echo request, an authentication message for using the echo server, and the like.

  The execution method of step 304 is to transmit an echo request message using, for example, HTTP (Hyper Text Transfer Protocol) or UDP (User Datagram Protocol), and the echo server returns a corresponding echo message to the transmission source. When the echo server receives the message, it returns a message to the transmission source, so that it can be easily known whether the message can reach the echo server. Next, when a predetermined time elapses after the message is received or transmitted, it is determined whether the message has been received (305). When a message is received from the echo server, this NIC is expected to be connected to the WAN side, so the processing ends. If the message cannot be received from the echo server, the NIC is expected to be connected to the LAN side, so first the LAN function is set (306). This step is equivalent to starting the LAN function providing unit 209. For example, the operation for starting an interface for managing a connection automatic control device or a home server integrated with the connection automatic control device as a LAN function, etc. is there. Next, the switch 207 is switched to connect to the LAN function providing unit (307). This flow provides WAN functions for the WAN and LAN functions for the LAN.

  FIG. 4 is a WAN / LAN connection automatic control flowchart when the connection automatic control device and the echo server are installed in the LAN. Note that this flow is equivalent to the flow 301 to 307, in which the condition judgment of 305 is reversed. This flow is executed independently for all NICs. The echo server existing in the LAN is, for example, an echo function provided by a personal PC (Personal Computer) connected to the network. In step 405, when the message is received, since this NIC is connected to the LAN side, the LAN function is set (406), and the switch switching process is performed (407). If the message cannot be received, this NIC is connected to the WAN side, so the processing ends. This flow provides WAN functions for the WAN and LAN functions for the LAN.

  FIG. 5 is a flowchart of a method that uses an echo server as little as possible. This flow is a process executed for all NICs. When the processing is started, the WAN function is set (501). This step is equivalent to activating the WAN function providing unit 208. Next, the switch 207 is switched so that each NIC is connected to the WAN function providing unit (502). When this step is executed, the packet transmitted via 202 and 203 always reaches the WAN function providing unit 208.

  Next, an address is acquired using DHCP (503). This step is equivalent to the flowchart of FIG. 6, but it is assumed that an address is acquired from the DHCP server. When an address is acquired by Auto IP, etc., it is processed as an address cannot be acquired. Next, a determination process is executed for the acquired address (504). If there is at least one NIC that has acquired the global address among all the NICs, the NIC that has acquired the global address receives all receivable packets (505). All receivable packets are packets that include packets whose destination is not this NIC.

  If all NICs have acquired private addresses in 504, the same processing as the confirmation by echo described in FIGS. 3 and 4 is performed (507). If all the NICs cannot acquire the address at 504, the normal setting cannot be made because the connection to the normal WAN is not possible (511). When the packet is received at 505, it is determined whether the WAN / LAN can be determined (506). WAN / LAN is distinguishable when the NIC receives the packet, and the source address of the received packet is only one of the global address and the private address for one NIC.

  If two or more packets are received for one NIC and the source address of the packet includes both a global address and a private address, is the NIC connected to the WAN or LAN? Cannot be determined. If it is possible to determine which of the WAN / LAN is connected in 506, the LAN function is set (508).

  In 506, if it is impossible to determine which of the WAN / LAN is connected, echo confirmation is performed (507). Note that the branch destination of 506 may be different for each NIC. For example, if there are three NICs, each of which is NIC-1, NIC-2, and NIC-3, NIC-1 and NIC-2 may perform 508, and NIC-3 may perform 507. When echo confirmation processing is performed in 507, it is determined whether or not an echo has been acquired (509). If the echo is acquired, LAN function setting processing is performed (508). If the echo cannot be acquired, automatic setting disable processing is performed (511).

  In step 510, the corresponding switch is switched by packet or echo. If the received packet has a global address, the NIC that received the packet connects to the WAN function provider. If the received packet has a local address, the NIC that receives the packet connects to the LAN function provider. If the acquired echo is a message from the WAN echo server, the NIC that has received the message connects to the WAN function provider. If the acquired echo is a message from the LAN echo server, the NIC that received the message connects to the LAN function provider. In the automatic setting disable process 511, for example, a process of displaying a message indicating that automatic setting cannot be performed to the user is performed.

  FIG. 6 is a flowchart of NIC address acquisition. When the process is started, the DHCP client corresponding to the NIC is activated (601). The DHCP client performs a DHCP address acquisition process for a certain period of time. If the address can be acquired, the process ends (602). If the address could not be acquired, an auto IP that automatically generates an IP address with reference to a MAC (Media Access Control) address or the like is activated (603). Next, it is determined whether an address has been acquired (604). If the address can be acquired, the process ends. If the address cannot be acquired due to a cause such as a case where the MAC address cannot be acquired, an address acquisition impossible process is performed (605). The address unacquisition process is a process such as displaying a message to the user that the corresponding NIC cannot acquire an address.

  Applicable to all network devices with one or more NICs.

System configuration diagram of automatic connection control device / WAN / LAN / DHCP server / echo server. Explanatory drawing of the connection automatic control apparatus when having two NICs. Flowchart for explaining an automatic connection control method when an echo server is installed in a WAN. Flowchart explaining an automatic connection control method when an echo server is installed in a LAN. An explanatory flow chart of a connection automatic control method when not using an echo server as much as possible. An explanatory flowchart of a method by which a NIC acquires an address.

Explanation of symbols

101 ... WAN (Wide Area Network)
102 ... WAN / LAN connection automatic control device 103 ... LAN (Local Area Network)
104 ... DHCP (Dynamic Host Configuration Protocol) server 105 ... Echo server

Claims (8)

A network interface;
WAN function provider that provides WAN functions;
A LAN function provider that provides LAN functions;
A switch unit for changing the connection between the network interface and the WAN function providing unit and the LAN function providing unit;
Means for detecting the WAN / LAN of the network to which the network interface is connected,
The WAN / LAN connection automatic control device, wherein the switch unit connects a network interface, a WAN function providing unit, and a LAN function providing unit in conjunction with a means for detecting WAN / LAN. The WAN / LAN connection automatic control device according to claim 1,
A WAN / LAN connection automatic control device comprising a router function between a WAN function providing unit and a LAN function providing unit. Automatic control of WAN / LAN connection connected to the network that automatically controls the connection between the network interface and the WAN function provider that provides WAN functions and the LAN function provider that provides LAN functions Means for receiving an echo request message sent from the device;
An echo server comprising means for returning an echo message to the WAN / LAN connection automatic control device in response to the echo request message. A WAN / LAN connection method in a WAN / LAN connection automatic control apparatus having a network interface, a WAN function providing unit that provides a WAN function, and a LAN function providing unit that provides a LAN function,
Detecting the WAN / LAN of the network to which the network interface is connected;
A WAN / LAN connection comprising: automatically controlling connection between the network interface and the WAN function providing unit and the LAN function providing unit according to a result of the step of detecting the WAN / LAN Method. The WAN / LAN connection automatic control device according to claim 1,
Control to set the function for WAN,
After controlling to set the WAN function, control to connect the switch unit to the WAN function,
After controlling the switch unit to connect to the WAN function, control to acquire an address via the network interface,
After acquiring the address, control to send an echo request message to the echo server connected to the network to which the network interface is connected,
If you do not receive an echo message, control to set the LAN function,
A WAN / LAN connection automatic control apparatus, characterized in that after setting a LAN function, the switch unit is controlled to connect to the LAN function. The WAN / LAN connection automatic control device according to claim 1,
Control to set the function for WAN,
After controlling to set the WAN function, control the switch unit to connect to the WAN function,
After controlling the switch unit to connect to the WAN function, control to acquire an address via the network interface,
After acquiring the address, control to send an echo request message to the echo server connected to the network to which the network interface is connected,
If an echo message is received, control to set the WAN function,
A WAN / LAN connection automatic control apparatus, wherein after setting a WAN function, the switch unit is controlled to connect to the WAN function. The WAN / LAN connection automatic control device according to claim 1,
Control to set the function for WAN,
After setting the WAN function, control the switch so that all network interfaces are connected to the WAN function.
After controlling the switch, control so that all network interfaces obtain addresses by DHCP,
Control to receive a packet when there are one or more network interfaces whose acquired address is a global address,
If all addresses acquired by the network interface are private addresses, control to check for echo,
If the network interface is unable to obtain an address, control to perform automatic setting disable processing,
If the packet is WAN / LAN distinguishable after receiving the packet, control to set the LAN function,
If the packet is not WAN / LAN discriminable after receiving the packet, control to check the echo,
After confirming the echo, if you get an echo message, control to set the LAN function,
After confirming the echo, if the echo message could not be obtained, control to perform the automatic setting impossible process,
A WAN / LAN connection automatic control apparatus characterized by controlling the switch unit so that a network interface is connected to a LAN function after setting the LAN function. The WAN / LAN connection automatic control device according to claim 1,
Control to start DHCP client as address acquisition function,
If the address cannot be acquired as a DHCP client, control to start Auto IP,
A WAN / LAN connection automatic control device that performs control so as to perform address acquisition impossible processing when an address cannot be acquired by auto IP.

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