Ipv6 over ipv4 transition method and apparatus for improving performance of control server

The present invention relates to a server-based IPv6-IPv4 transition method and device, and more particularly to a control server-based IPv6-IPv4 transition method and device for improving the performance of a control server.

Generally, the IPv6-IPv4 conversion method of the control server infrastructure is a control server so that the service terminal can register its own service in the control server and request the address-translated information of the terminal to be communicated with. A method of creating a control tunnel to (RFC2529, also known as RFC3053). By using the generated control tunnel, the IPv6 terminal can request the control server for an IPv4 address that can communicate with the IPv6 address of the receiving terminal (the other party) and acquire the IPv4 address. Such information is managed by transmitting a tunnel creation request message to the control server and registering itself with the control server when each terminal first creates a control tunnel.

On the other hand, conventional methods for IPv6-IPv4 conversion include a translation method and a server infrastructure conversion method.

The above-mentioned translation method is a method in which IPv6 and IPv4 can be linked by providing an address translator between two IP networks of different versions. Such a method has a problem of extensibility that address translation must be performed for all packets.

The server infrastructure conversion (IPv6-IPv4 conversion) method described above can be divided into a tunnel broker (RFC3053), a tered (Teredo), and an ISATAP (Intra-Site Automatic Tunnel Addressing Protocol).

The tunnel broker is a device for relaying a tunnel, and a terminal in the IPv4 network creates a tunnel to a gateway between the IPv4 network and the IPv6 network. Here, the generation of the control tunnel means that the terminal located in the IPv4 network registers its own information in the server in order to communicate with the terminal in the IPv6 network, and acquires the information in order to communicate with the other party. enable.

Tered then uses a method similar to the tunnel broker method described above, but has not been officially assigned by the IANA (Internet Assigned Numbers Authority). However, in such a method, the prefix for tered is defined separately, and the protocol is designed to include the possibility that the terminal in the IPv4 network is under NAT (Network Address Translation). However, although the above tunnel broker method describes only the general structure of RFC3063, it is actually implemented in consideration of address translation and the like, so there is not much difference between the tered and the tunnel broker method. In addition, since Teledo can extract an IPv4 address from an IPv6 address, it can communicate directly with each other without going through a device such as a Teredo relay, which is the difference between the two methods. Is.

On the other hand, ISATAP is a terminal for providing communication between a terminal existing in an IPv4 intranet and another terminal of the intranet, or a terminal existing in an IPv6 public network connected to the intranet. An automatic tunneling method between terminals or routers. Such a method is a protocol that has not yet been standardized by RFC, but is basically provided by Microsoft's Windows® operating system. The ISATAP address has a :: 0: 5 EFE: wxyz interface identifier, where wxyz is an IPv4 address. The ISATAP interface identifier can be combined with a valid 64-bit prefix for the IPv6 unicast address.

Thus, ISATAP addresses are IPv4 source and destination addresses used to carry ISATAP traffic over IPv4 networks, such as IPv4-compatible addresses, 6 over 4 addresses, and 6 to 4 addresses. ) Is included.

However, the above-mentioned general IPv6-IPv4 conversion method has a problem that the number of control tunnels increases as the number of service terminals increases, and the burden on the tunnel management of the control server is increased. This is because the control server measures the lifetime of each control tunnel and deletes or maintains the control tunnel when the terminal service ends. Further, the control server can transfer the transmission of data to the communicating terminal via the control tunnel. As mentioned above, maintaining the control tunnel and transferring data through the control tunnel causes a decrease in server performance.

<p><patcit num="1"><text>Korean Patent Publication No. 2006-0111810</text></patcit></p>

<p> Therefore, an object of the present invention is to easily manage a control tunnel regardless of an increase in the number of service terminals, enable data forwarding through the tunnel, and improve the performance and service stability of the control server. To provide IPv6-IPv4 conversion methods and devices for this purpose.</p>

<p> In order to achieve the above-mentioned object of the present invention, according to one aspect of the present invention, in a router connected between an IPv6 terminal and a control server, IPv6-IPv4 conversion is performed in order to improve the performance of the control server. A method is provided in which the method is to receive a tunnel generation request message from the control server that operates in response to the tunnel generation request of the IPv6 terminal, and a tunnel generation response message for the received tunnel generation request message. Is included to the IPv6 terminal via the control server, and IPv6-IPv4 conversion is performed via the tunnel generated by the IPv6 terminal that has received the tunnel generation response message. And.</p><p> According to another aspect of the present invention for achieving the above-described object of the present invention, in a control server connected between an IPv6 terminal and a plurality of routers in order to improve the performance of the control server, the control server A method of performing IPv6-IPv4 conversion is provided in order to improve its own performance, and the method includes a step of receiving a tunnel generation request message from the above-mentioned IPv6 terminal existing in the above-mentioned IPv4 network via the above-mentioned IPv4 network, and a step of receiving a tunnel generation request message in advance. A step of selecting an edge router from among the registered routers to generate a tunnel between the terminal router and the IPv6 terminal, and a step of transmitting a tunnel generation request message to the selected terminal router. A step of receiving the tunnel generation response message corresponding to the tunnel generation request message from the selected terminal router and transmitting the received tunnel generation response message to the IPv6 terminal, and the tunnel generation response message. It is characterized by including a step of receiving an IPv6-IPv4 converted message from the terminal router when the message is received and transmitted to the terminal router via a tunnel generated from the IPv6 terminal. To do.</p><p> According to another aspect of the present invention for achieving the above object of the present invention, as a device connected between an IPv6 terminal and a control server to perform IPv6-IPv4 conversion, the above-mentioned IPv6 terminal and the above-mentioned IPv6 terminal via the above-mentioned IPv4 network. An IPv6 terminal interface unit that interfaces and sets a tunnel with the IPv6 terminal to send and receive messages, and the device is selected by the control server as a terminal router for tunnel setting and receives a tunnel generation request message from the control server. Then, a tunnel generation response message containing information about the device itself is transmitted to the control server, and when the IPv6 terminal receives the tunnel generation response message from the control server and generates a tunnel, IPv6-IPv4 conversion is performed. , The forwarding control unit, the routing table that registers the routing information included in the tunnel generation request message, and when a message is received from the IPv6 terminal via the generated tunnel, it interfaces with the control server via IPv6. It is characterized by including a control server interface unit.</p>

<p> As described above, the present invention can easily manage the control tunnel regardless of the increase in the number of service terminals by generating the control tunnel between the terminal router selected by the control server and the terminal. , Data transfer is possible. Therefore, it is possible to prevent the load on the control server caused by setting the control tunnel to the control server on all terminals, improve the performance of the control server, improve the stability of the service, and increase the number of subscribers. It has the effect of guaranteeing the expandability of services due to the increase.</p>

<figref num="1">It is a figure which shows the tunnel configuration through the terminal router in the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention.</figref><figref num="2">It is a figure which shows the detailed structure of the termination router by one Embodiment of this invention.</figref><figref num="3">It is a figure which shows the procedure for setting the tunnel through the terminal router in the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention.</figref><figref num="4">It is a figure which shows the operation performed by the control server to determine the router which generates the tunnel from the terminal by one Embodiment of this invention.</figref><figref num="5">It is a figure which shows the tunnel request message transmitted from the control server of the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention to a router.</figref><figref num="6">It is a figure which shows the tunnel response message transmitted from the tunnel termination router of the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention to a control server.</figref><figref num="7">It is a figure which shows the control message packet processing operation for performing IPv6-IPv4 conversion by one Embodiment of this invention.</figref><figref num="8">It is a figure which shows the data transfer in the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention.</figref><figref num="9">It is a figure which shows the operation of confirming the connection between the terminal router and the control server in the IPv6-IPv4 conversion system of the server base by one Embodiment of this invention.</figref>

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Similar reference numerals indicate similar components throughout the specification. Further, in the description of the present invention, a specific description of a known function or configuration may be omitted so as not to interfere with the understanding of the present invention.

FIG. 1 is a diagram showing an IPv6-IPv4 conversion system of a server infrastructure including a tunnel termination router and a server according to an embodiment of the present invention.

Referring to FIG. 1, an IPv6-IPv4 conversion system consists of a plurality of terminals 101, a plurality of routers 102 for forming a tunnel (IPv6-IPv4 tunnel; hereinafter referred to as a control tunnel), and a tunnel from a specific terminal 101. To select a terminal router 102 for an available tunnel in response to a generation request and to send a message to / receive a message from the terminal 101 via the selected terminal router 102. Control server 103 and.

The terminal 101 is an IPv6 terminal, requests the control server 103 to create a tunnel, and creates a control tunnel by using the terminal router 102 according to the result of the request.

The terminating router 102 can be configured as a dual stack router capable of processing both IPv4 and IPv6 data. Further, the terminal router 102 communicates with the terminal 101 requesting tunnel generation via the control tunnel, and can transmit an IPv4 / IPv6 message (tunnel generation request message), so that the transmission control protocol (TCP) can be transmitted. IPv6 communication with the control server 103 is performed through protocol). Further, when the terminating router 102 attempts the first connection with the control server 103, the terminating router 102 transmits a message for registration request (Init Msg.) To the control server 103 to notify the existence of the terminating router itself. , Transmits the number of tunnels currently configured and the number of tunnels that can be added to configure.

The control server 103 adds (registers) new routers as the number of IPv6 terminals 101 increases, stores information about the added routers, and periodically checks the status information about the added routers. , Recognize whether the added router can be used. Then, the control server 103 determines the terminal router for forming the tunnel with the terminal 101 from the plurality of registered routers according to the number of tunnels and the availability.

In the IPv6-IPv4 conversion system having the above configuration, the structure of the terminal router 102, which is a device for converting the communication between the terminal 101 and the control server 103 via the generated tunnel, is shown in FIG. 2 below. It will be described more specifically with reference.

FIG. 2 is a diagram showing a detailed configuration of a terminal router according to an embodiment of the present invention.

Referring to FIG. 2, the terminating router 102 includes an IPv6 terminal interface 111, a forwarding controller 112, a routing table 113, and a control server interface 114.

The IPv6 terminal interface 111 interfaces with the terminal 110 via an IPv4 network and sets up a tunnel with the terminal 110 to send and receive messages.

The transfer control unit 112 is selected by the control server 103 as the terminal router for setting the tunnel, receives the tunnel generation request message from the control server 103, and receives the information contained in the tunnel generation request message received from the control server 103. Generate a tunnel interface by using it. Further, when the terminal 101 receives the tunnel generation request message from the control server 103 and generates a tunnel, the transfer control unit 112 converts the communication between the terminal 101 and the control server 103 via the generated tunnel (IPv6). -IPv4 conversion). Further, the transfer control unit 112 controls the transfer of IPv6 data, notifies the control server 103 of its existence for tunnel generation, and transmits its own state information and the information registered in the routing table 113. Here, the state information includes the number of tunnels currently set in the terminal router 102, the number of tunnels that can be added for setting, and the like.

The routing table 113 registers the routing information (IPv4 and IPv6 addresses, etc.) related to the tunnel interface generated by the transfer control unit 112.

The control server interface 114 provides an interface for communication with the control server 103 connected via TCP, and when a message is received from the terminal 101 via the generated tunnel, the control server interface 114 interfaces with the control server 103 via IPv6. I do.

Further, the process for setting the tunnel between the IPv6 terminal and the control server via the router will be described in detail in relation to FIG.

FIG. 3 is a diagram showing a process for setting a tunnel via a router in a server-based IPv6-IPv4 conversion system according to an embodiment of the present invention.

Referring to FIG. 3, in step 201, terminal 101 transmits a tunnel generation request message to router 102 over the IPv4 network. Then, the router 102 transmits the tunnel generation request message to the control server 103 by the message relay. Here, since the control tunnel (referred to as IPv6-IPv4 tunnel) from the terminal 101 has not yet been generated and is requested by the IPv4 message type, the tunnel generation request message is transmitted by the IPv4 message type.

Further, in step 202, the control server 103 that received the tunnel generation message stores information about the terminal (NAT, Port, IPv4 private address, IPv4 global address, IPv6 address, etc.), and determines the current number of tunnels. The termination router 102 of the tunnel for substantially generating the control tunnel is selected from the plurality of routers 102 in consideration of the utility of the tunnel.

Therefore, the selected terminating router 102 receives the tunnel generation request message from the control server 103 in step 203, and the selected terminating router 102 transmits the tunnel generation response message to the control server 103 in step 204. At this time, the selected terminal router 102 generates a tunnel interface by using the information included in the tunnel generation request message, and registers the routing information for the tunnel interface in the routing table 113.

Therefore, in step 205, the terminating router 102 transmits the received tunnel generation response message including the information for tunnel generation to the terminal 101 via the control server 103. Then, in step 206, terminal 101 creates a control tunnel to the terminating router 102 by using the information contained in the tunnel generation response message. Here, the terminal 101 requests the control server 103 for information about the receiving terminal to communicate with via the generated control tunnel. That is, the terminal 101 sets up a control tunnel in the router 102, whereby the router 102 communicates with the control server 103 via IPv6.

The operation of the control server in such a tunnel setting procedure will be described in more detail with reference to FIG.

FIG. 4 is a diagram showing an operation performed by a control server to determine a router that creates a tunnel from a specific terminal according to an embodiment of the present invention.

Referring to FIG. 4, in step 301, when the new router requests registration, control server 103 adds (registers) the new router, and in step 302, control server 103 is in the tunnel configured by the new router. Stores information about the number or types of tunnels available and sets up the connection. By registering the required number of new routers with the control server 103 as the number of service terminals increases, it is possible to select an appropriate router from the registered routers as the terminal router 102 for creating a tunnel. It will be possible.

Then, in step 303, when the control server 103 receives the tunnel generation request message from the terminal 101, the control server 103 takes out the terminal router information stored in advance in step 304, and the terminal 101 is taken out from the registered router. Select a terminal router to create a tunnel with. At this time, the control server 103 determines the number of tunnels per router, the availability of tunnels, and the amount of data used for the tunnels, and selects the appropriate router (which is the least burdensome).

Then, in step 305, the control server 103 transmits a tunnel generation request message to the selected terminating router 102 to instruct the tunnel to be configured, and in step 306, the selected terminating router 102 responds to the tunnel configuration. The tunnel generation response message including the result is received, and in step 307, the received tunnel generation response message is transmitted to the terminal 101. Here, the structure of the tunnel generation request message is as shown in FIG. The tunnel generation request message contains the fields of IP header, cmd, Type, Nat, lifetime, terminal IPv4 address (called CoA (Care of Address)), and terminal IPv6 address, and when the terminal belongs to CoA and Nat. , The tunnel generation request message further includes a private CoA field. Here, the cmd field represents the operation, the Type field represents the type of tunnel (eg IPv6-IPv4), and the NatPort indicates whether the terminal belongs to the nut (Nat).

The structure of the tunnel generated response message is as illustrated in Figure 6 and includes the IP header, cmd, result, Reason, and IPv6 address fields for the terminal. Here, the Result field represents the tunnel setting result, and the Reason field represents the cause when the failure occurs.

The operation for generating a control tunnel in an IPv6-IPv4 system and processing control message packets sent and received via the generated control tunnel will be specifically described with reference to FIG. 7.

FIG. 7 is a diagram showing a control message packet processing operation for IPv6-IPv4 conversion according to an embodiment of the present invention.

Referring to FIG. 7, in step 401, the control server 103 receives the control tunnel generation request message from the terminal 101 via IPv4. As a result, in step 402, the control server 103 transmits the control tunnel generation request message to the router 102, receives the control tunnel generation response message from the router 102, and then transmits the control tunnel generation response message to the terminal 101.

The terminal 101 receives the control tunnel generation response message and generates a control tunnel. Then, in step 405, the terminal 101 requests the control server 103 for information on the receiving terminal to be communicated with using the generated control tunnel. At this time, an IPv6-IPv4 control tunnel is used. In this case, the IPv4 header contains information that includes the router 102 located at the end of the tunnel as the destination, and the IPv6 header contains information that includes the control server 103 as the destination.

Therefore, in step 406, since the IPv4 header included in the information request message indicates the router 102, the router 102 performs IPv6 lookup and displays the information request message of the receiving terminal including the lookup information. , Communicate to control server 103. Then, in step 407, the terminating router 102 receives a response message to the above information request from the control server 103. As a result, in step 408, the router 102 transmits a response message to the information request destined for the terminal 101 via the control tunnel.

The data transfer between the transmitting terminal and the receiving terminal using the generated control tunnel as described above is as shown in FIG. Here, since the IPv6 routing information is set in the router at the time of generating the control tunnel, data transfer using the control tunnel becomes possible. Referring to FIG. 8, a first control tunnel is generated between the transmitting terminal 101 and the terminal router 102, and the packet transferred through the first control tunnel has data in the payload interval. It includes the information of the receiving terminal in the IPv6 and IPv4 headers, and the information of the router 102 in the IPv4 header. Further, a second control tunnel is generated between the router 102 and the receiving terminal 104, and the packet transferred through the second control tunnel contains data in the payload section and is received in the IPv6 header and the IPv4 header. Contains terminal information.

As illustrated in FIG. 9, the router 102 and the control server 103 periodically check each other's status using a TCP connection.

Referring to FIG. 9, when router 102 attempts to connect to control server 103 in step 501, router 102 first transmits a message for registration request (Init Msg.) To control server 103 itself. And conveys information about the number of tunnels configured on the router 102 itself and the number of tunnels that can be added to configure (usable amount). After that, the control server 103 confirms whether or not the terminal router 102 is available (serviceable state) by using the received information, and terminates the registration request response message including its own information (address). Transmit to router 102.

Therefore, the router 102 receives the registration request response message from the control server 103 in step 502, and sets up a connection with the control server 103 in step 503.

Then, in step 504, the router 102 receives the state information request message for periodic state management from the control server 103, and in step 505, the router 102 transmits the state information response message to the control server 103. As a result, the control server 103 can periodically check whether or not the router 102 is in a usable state. At this time, if there is no response within a predetermined time, the control server 103 recognizes that the terminal router 102 is not an available router and does not transmit the tunnel generation message.

The present invention has been specifically shown and described in the context of exemplary embodiments, but as defined by the claims, various modifications within the technical ideas and scope of the invention. Will be understood by those skilled in the art.