JP3789392B2 - PPPoE built-in router and global IP address assignment method thereof - Google Patents

Description

[0001]
[Industrial application fields]
The present invention relates to a PPPoE built-in router provided with PPPoE (Point to Point Protocol over Ethernet (registered trademark)). In particular, the present invention relates to a global IP address assignment method for assigning a global IP (Internet Protocol) address to a plurality of terminals and simultaneously accessing the Internet when playing an online game.
[0002]
[Prior art]
A terminal that constitutes a LAN (Local Area Network) is usually connected to the Internet via a router having a NAT (Network Address Translation) function and an IP masquerade function. The function of NAT and the function of IP masquerade are well known as described in JP 2000-59430 A and JP 2000-341337 A.
[0003]
NAT is a function that converts a private IP address used on a LAN to a global IP address and sends it to the Internet, and conversely converts a global IP address that arrives from the Internet to a private IP address and sends it to the LAN. is there. Thus, the global IP address is assigned to the router, not the terminal.
[0004]
IP masquerading also converts private IP addresses together with TCP (Transmission Control Protocol) / UDP (User Datagram Protocol) source port numbers, thereby sharing one global IP address among multiple terminals, thereby depleting global IP addresses. It is a function to avoid. Similarly, a global IP address is assigned to a router, not a terminal. Note that IP masquerading is also included in NAT in that it performs mutual conversion between a global IP address and a private IP address.
[0005]
By the way, when a terminal on the LAN side plays an online game via the Internet, port forwarding must be set in the terminal that plays the game in order to pass a connection request from the game opponent.
[0006]
[Problems to be solved by the invention]
However, in the port forwarding setting, a global IP address is assigned to a terminal, not to a router. Therefore, when another terminal in the LAN plays an online game, another global IP address must be assigned to the terminal. In other words, there is a problem that the number of global IP addresses to be used increases and causes exhaustion.
[0007]
Therefore, in view of the above problems, the present invention provides a PPPoE built-in router and a global IP address assignment method thereof that enable online games to be simultaneously performed on a plurality of terminals in a LAN via the Internet with the same global IP address. The purpose is to do.
[0008]
[Means for Solving the Problems]
In order to solve the above problems, the present invention provides a PPPoE built-in router for connecting a plurality of terminals to the Internet, a PPPoE session ID assigned to each of the terminals with which a session has been established, an application port number, A PPPoE session by assigning a common global IP address to each of the terminals, a port number conversion unit for storing a port number obtained by converting an application port number when an IP packet is transmitted from the PPPoE built-in router to the Internet corresponding to the ID to send the IP packet converts the port number of the application to the Internet from the PPPoE built router, the port number of the IP packet received by the PPPoE internal router from the Internet, said port Referring to No. converting unit converts the port number of the application, to restore the session ID of the corresponding PPPoE identifies terminal, further comprising a PPPoE control unit to be transmitted to the terminal which identifies the IP packet received A PPPoE built-in router is provided.
[0009]
By this means, the port number converted by each terminal in the plurality of terminals in the LAN via the Internet with the same global IP address corresponds to the PPPoE session ID, so that online games can be performed simultaneously. Become.
By using the port number after conversion, it is possible to avoid port scanning from the outside.
Since a generally popular protocol called PPPo E is used, a large new cost is not generated.
[0010]
Further, the PPPoE control unit specifies a source address of a terminal that establishes a PPP session in the PPPo E discovery stage, sets a PPPoE session ID, and stores the PPPoE session ID in the port number conversion unit.
By this means, it is possible to identify whether or not each terminal has the same global IP address but the IP packet addressed to itself by the PPPoE session ID without depending on the conventional private IP address.
[0011]
Further, the PPPoE control unit assigns the global IP address on the Internet to all the terminals that have established a session by IPCP negotiation.
By this means, it is possible to play an online game with the same global IP address at a plurality of terminals in the LAN without using NAT, so that IP address exhaustion can be avoided.
[0012]
Furthermore, the present invention provides a PPPoE built-in router global IP address assignment method for connecting a plurality of terminals to the Internet, a PPPoE session ID assigned to each of the terminals with which a session has been established, an application port number, Storing a port number converted at the time of transmission of an IP packet from the PPPoE built-in router to the Internet, and assigning a common global IP address to each of the terminals and corresponding to a session ID of PPPoE Referring and transmitting the converted port number the IP packet from the PPPoE internal router in the Internet, stored the PPPoE session ID, port number of the application, the converted the port number Converts the port number of the IP packet received by the PPPoE internal router from the Internet to the port number of the application, to identify the terminal to restore the session ID of the corresponding PPPoE, to the terminal which identifies the IP packet received And providing a global IP address assignment method for a PPPoE built-in router.
[0013]
By this means, the port number converted by each terminal in the plurality of terminals in the LAN via the Internet with the same global IP address corresponds to the PPPoE session ID, so that online games can be performed simultaneously. Become.
By using the port number after conversion, it is possible to avoid port scanning from the outside.
[0014]
Since a generally popular protocol called PPPo E is used, a large new cost is not generated.
[0015]
As shown in the figure, a PPPoE built-in router 101 is connected to the Internet 106, and the PPPoE built-in router 101 is connected to a plurality of terminals 103, 104, and 105 via an Ethernet (registered trademark) 102 interface. .
The PPPoE built-in router 101 is a router equipped with PPPo E. In the present invention, the terminal is identified by the session ID and the source port number of PPPo E without using the IP address conversion by NAT. A global IP address is assigned to allow simultaneous access to the Internet 106.
[0016]
Here, PPPo E is a protocol for realizing PPP (Point to Point Protocol) on the Ethernet (registered trademark) 102, and can have a plurality of PPPo E sessions on the Ethernet (registered trademark) 102.
Note that PPP is a protocol on the LAN that is performed in a one-to-one connection environment by telephone or ISDN line, and has functions such as user authentication and IP address assignment.
[0017]
The PPPoE built-in router 101 includes a PPPoE control unit 107 and a port number conversion unit 108.
The PPPoE control unit 107 of the PPPoE built-in router 101 connects a plurality of terminals 103, 104, and 015 on the Ethernet (registered trademark) 102 by PPPo E , assigns a unique session number to each terminal, and performs PPP negotiation. The same global IP address used on the Internet 106 is assigned to each of the plurality of terminals 103, 104, and 015.
[0018]
Port number conversion unit 108, as can be transmitted by converting rewrites the source port number of the IP packets transmitted by a plurality of terminals 103,104,015 to the Internet 106, and the session ID, the source port number The correspondence relationship with the converted transmission source port number is stored in the memory.
PPPoE control unit 107, when receiving an IP packet from the Internet 106 restores the session ID rewrites the source port number based on the correspondence relationship between the port number conversion unit 108, Ethernet (registered trademark) 102 To send.
[0019]
As described above, by the conversion of a session ID and source port number of PPPo E, since it is possible to identify the plurality of terminals 103,104,015, without assigning a private IP address to the terminal, a plurality of terminals 103, 104, and 015 can share the connection of the Internet 106 with a common global IP address.
FIG. 2 is a diagram showing a PPPo E frame format. As shown in the figure, the PPPo E frame is provided with an Ethernet (registered trademark) header, a PPPo E header, an IP header, a TCP (Transmission Control Protocol) header, and a PPPo E payload, and the Ethernet (registered trademark) header includes Includes DESTINATION ADDRESS (destination address), SOURCE ADDRESS (source address), ETHER TYPE, etc., PPPo E header has VER, TYPE, CODE, SESSION (session) ID, LENGTH, etc., IP header has DESTINATION IP ADDRESS (destination IP address), SOURCE IP ADDRESS (source IP address), TCP header with DESTINATION ORT, SOURCE PORT and the like are provided.
[0020]
FIG. 3 is a diagram for explaining the port number conversion table of the port number conversion unit 108 in the PPPoE built-in router 101.
As shown in this figure, the port number conversion table of the port number conversion unit 108 in the PPPoE built-in router 101 shows the correspondence between the session ID and transmission source port number of the IP packet transmitted by each terminal and the converted transmission source port number. It is a table that stores relationships.
[0021]
As an example, for the session ID = 0001 and the source port number = 3000, the converted source port number = 60000, for the session ID = 0002, the source port number = 3100, and the converted source port number = 61000. , Session ID = 0003 and source port number = 5000 are stored as converted source port number = 62000.
[0022]
In this way, it is possible to avoid external port scanning by using the converted source port number.
FIG. 4 is a diagram for explaining a connection procedure of the PPPoE control unit 107 in the PPPoE built-in router 101. As shown in this figure, when one terminal of a plurality of terminals 103, 104, and 015 connects to the Internet 106, a PADI (PPPo E Active Discovery Initiation) packet is sent to the entire network of the Ethernet (registered trademark) 102. The
[0023]
The PADI packet is transmitted to a broadcast address (DESTINATION ADDRESS = 0xffffffffffff in FIG. 2).
The PPPoE built-in router 101 receives the PADI packet and returns a PADO (PPPo E Active Discovery Offer) packet to the transmission source terminal.
[0024]
The terminal that receives the PADO packet addressed to itself sends back a PADR (PPPo E Active Discovery Request) packet to the PPPoE built-in router 101 to request the start of a PPPo E session.
In contrast, the PPPoE built-in router 101 sends back a PADS packet to which a unique session ID is added for each session in order to identify the session in the session ID field, thereby establishing a PPPo E session.
[0025]
In this way, the DESTINATION ADDRESS (MAC address) of the terminal that establishes the PPP session in the PPPo E discovery stage is specified, and the PPPo E session ID is set.
A data link is established by LCP (Link Control Protocol).
[0026]
Further, authentication is performed. Thereafter, PPP negotiation is started, and a global IP address on the Internet 106 is assigned by IPCP (Internet Protocol Control Protocol) negotiation.
Here, among the plurality of terminals 103, 104, and 015, the same global IP address is assigned to all the transmission source terminals.
[0027]
In this way, a PPP session is established at the PPP session stage to perform IP communication.
FIG. 5 is a flowchart for explaining a series of operations of the PPPoE built-in router 101 until the IP packets are transmitted when the terminals 103, 104, and 015 simultaneously play an online game.
[0028]
In step S <b> 201, first, the terminal 103 makes an online game connection request to the Ethernet (registered trademark) 102.
In step S202, the PPPoE control unit 107 of the PPPoE built-in router 101 performs a discovery stage process. That is, as described above, the PADI packet is transmitted from the terminal 103 to the entire network and the broadcast address (DESTINATION ADDRESS = 0xffffffffffff in FIG. 2). When the PPPoE control unit 107 receives a PADI packet, the PADO packet is returned to the terminal 103. When the PADO packet addressed to itself is received, the terminal 103 sends back a PADR packet to the PPPoE control unit 107 and requests the start of the PPPo E session.
[0029]
The PPPoE control unit 107 that has received the PADR packet generates a unique session ID = 0001 for each PPPo E session in the session ID field, adds it, and sends it back.
Furthermore, a global IP address acquired from the Internet 106 is assigned to the terminal 103 by IPCP negotiation in the PPP session stage.
[0030]
In step S203, the PPPoE control unit 107 that has received the transmission packet from the terminal 103 to the Internet 106 rewrites the transmission source port number = 3000 to the converted transmission source port number = 6000, and the port number conversion unit 108 receives the session ID. = 0001, transmission source port number = 3000, converted transmission source port number = 6000 are stored.
[0031]
In step S <b> 204, an IP packet with a converted source port number = 6000 and a global IP address is transmitted to the Internet 106.
Next, in step S205, when there is a connection request from the terminal 104 to the Internet 106, similarly, in step S206, the PPPoE control unit 107 of the PPPoE built-in router 101 performs processing of the discovery stage / PPP session stage. Session ID = 000 2 is generated, appended, and sent back.
[0032]
In step S207, the PPPoE control unit 107 that has received the transmission packet from the terminal 104 to the Internet 106 rewrites the transmission source port number = 3500 to the converted transmission source port number = 6100, and the port number conversion unit 108 receives the session ID. = 0002, source port number = 3500, and source port number after conversion = 6100 are stored.
[0033]
In step S <b> 208, an IP packet to which the same global IP address as that of the terminal 103 is assigned with the converted source port number = 6100 is transmitted to the Internet 106.
Next, in step S209, when there is a connection request from the terminal 105 to the Internet 106, similarly, in step S210, the PPPoE control unit 107 of the PPPoE built-in router 101 performs processing of the discovery stage / PPP session stage. Session ID = 0003 is generated, added, and sent back.
[0034]
In step S211, the PPPoE control unit 107 that has received the transmission packet from the terminal 105 to the Internet 106 rewrites the transmission source port number = 5000 to the converted transmission source port number = 6200, and the port number conversion unit 108 receives the session ID. = 0003, transmission source port number = 5000, converted transmission source port number = 6200 are stored.
[0035]
In step S 212, an IP packet to which the source port number after conversion = 6200 and the same global IP address as that of the terminals 103 and 104 are assigned is transmitted to the Internet 106. The transmission process ends.
FIG. 6 is a flowchart for explaining a series of operation examples of the PPPoE built-in router 101 when an IP packet is received from the Internet 106 during an online game.
[0036]
In step S221, it is determined whether an IP packet having a destination IP address from the Internet 106 is received. If not received, the receiving process is terminated.
In step S222, if the IP packet of the destination IP address to itself is received, it is determined whether or not the destination port number of the received IP packet is 6000. If the destination port number is not 6000, the process proceeds to step S224.
[0037]
In step S223, if the destination port number is 6000, the port number conversion unit 108 is referred to, the destination port number is rewritten to 3000, restored to the IP packet with session ID = 0001, transmitted to the terminal 103, and received. The process ends.
In step S224, it is determined whether or not the destination port number of the received IP packet is 6100. If the destination port number is not 6100, the process proceeds to step S226.
[0038]
If the destination port number = 6100 in step S225, the port number conversion unit 108 is referred to, the destination port number = 3500 is rewritten, the IP packet of session ID = 0002 is restored, transmitted to the terminal 104, and received. The process ends.
In step S226, it is determined whether or not the destination port number of the received IP packet is 6200. If the destination port number is not 6200, the reception process is terminated.
[0039]
If the destination port number = 6200 in step S225, the port number conversion unit 108 is referred to, rewritten to the destination port number = 5000, restored to the IP packet with the session ID = 0003, transmitted to the terminal 105, and received. The process ends.
In this way, the IP addresses of the terminals 103, 104, and 105 are all the same global IP address, but each terminal can identify whether or not it is an IP packet addressed to itself by the session ID.
[0040]
Furthermore, in the present invention, since a generally popular protocol called PPPo E is used, a large new cost burden does not occur.
[0041]
【The invention's effect】
As described above, according to the present invention, the session ID given to the terminal with which the session has been established, the port number of the application, and the port number converted when the IP packet is transmitted from the PPPoE built-in router to the Internet. Store, assign a common global IP address to the terminal and send an IP packet from the router with built-in PPPoE to the Internet, and refer to the stored session ID, application port number, converted port number, and incorporate PPPoE from the Internet Since the port number of the IP packet received by the router is converted to the port number of the application, the corresponding session ID is restored to identify the terminal, and the received IP packet is transmitted to the identified terminal. Same on multiple terminals Via the Internet in the global IP address, online games is possible at the same time.
[0042]
By using the port number after conversion, it is possible to avoid port scanning from the outside.
Since a generally popular protocol called PPPo E is used, a large new cost is not generated.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a schematic configuration of a PPPoE built-in router according to the present invention.
FIG. 2 is a diagram illustrating a PPPo E frame format;
3 is a diagram illustrating a port number conversion table of a port number conversion unit 108 in the PPPoE built-in router 101. FIG.
FIG. 4 is a diagram illustrating a connection procedure of a PPPoE control unit 107 in a PPPoE built-in router 101.
FIG. 5 is a flowchart for explaining a series of operations of the PPPoE built-in router 101 until an IP packet is transmitted when terminals 103, 104, and 015 simultaneously play an online game.
FIG. 6 is a flowchart for explaining a series of operation examples of the PPPoE built-in router 101 when an IP packet is received from the Internet 106 during an online game.

Claims (4)

In a PPPoE built-in router for connecting multiple terminals to the Internet,
Stores the PPPoE session ID assigned to each of the terminals with which a session has been established, the application port number, and the port number obtained by converting the application port number when the IP packet is transmitted from the PPPoE built-in router to the Internet. A port number conversion unit to
A common global IP address is assigned to each of the terminals , an application port number is converted in accordance with a PPPoE session ID, and an IP packet is transmitted from the PPPoE built-in router to the Internet, and from the Internet to the PPPoE built-in router. The port number of the received IP packet is converted to the application port number with reference to the port number conversion unit, the corresponding PPPoE session ID is restored to identify the terminal, and the received IP packet is identified. A PPPoE built-in router comprising a PPPoE control unit for transmitting to a terminal. The PPPoE control unit identifies a source address of a terminal that establishes a PPP session in a PPPo E discovery stage, sets a PPPoE session ID, and stores the session ID in the port number conversion unit. The PPPoE built-in router described in 1. The PPPoE built-in router according to claim 1, wherein the PPPoE control unit assigns the global IP address on the Internet to all the terminals that have established a session by IPCP negotiation. In the global IP address assignment method of a PPPoE built-in router for connecting a plurality of terminals to the Internet,
Stores the PPPoE session ID assigned to each of the terminals with which a session has been established, the application port number, and the port number obtained by converting the application port number when the IP packet is transmitted from the PPPoE built-in router to the Internet. And a process of
Assigning a common global IP address to each of the terminals , converting an application port number corresponding to a PPPoE session ID, and transmitting the IP packet from the PPPoE built-in router to the Internet;
With reference to the stored session ID of the PPPoE, the port number of the application, and the converted port number, the port number of the IP packet received by the router with built-in PPPoE from the Internet is converted to the port number of the application, And a method of identifying a terminal by restoring a corresponding PPPoE session ID, and transmitting the received IP packet to the identified terminal.

Images