JP4352645B2 - Terminal device, relay device, communication method, and recording medium recording the communication program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a terminal device, a relay device, a communication method, and a recording medium recording the communication program, and relates to an address conversion method between a plurality of networks configured by different address systems.
[0002]
[Prior art]
In recent years, the spread of the Internet based on the IPv4 (Internet Protocol version 4) technology described in "Internet Protocol-DARPA Internet Program Protocol Specification, RFC791" has been remarkable, In addition to expansion in the subscriber phone and ISDN markets, mobile devices such as the appearance of systems using WAP (Wireless Application Protocol) technology described in "Wireless Application Protocol Architectural Overview, WAP Architecture Version 30-Apr-1988" The telecom market has also been targeted.
[0003]
In order to connect a terminal device to the Internet for data communication, an address (IP address) for identifying the terminal device on the Internet is required. An IP address has a 32-bit address space, and an IP address (global address) assigned to a terminal device communicating on the Internet must be unique on the Internet. For this reason, the lack of addresses to be assigned to terminal devices has become a problem with the spread of the Internet and the accompanying increase in terminal devices. Note that the IP address assignment is managed worldwide by the US IANA (Internet Assigned Numbers Authority), and the user cannot basically assign it to a terminal device without permission.
[0004]
In order to solve such a problem, the application of IPv6 (Internet Protocol version 6) technology described in “Internet Protocol, Version 6 (IPv6) Specification, RFC2460” has been decided in the long term. In the current Internet, which is widely used in technology, a solution on the IPv4 technology is required as an actual solution until IPv6 becomes popular.
[0005]
As conventional techniques for solving this problem in IPv4 technology, NAT (Network Address Translator) technology described in “The IP Network Address Translator (NAT), RFC1631”, “IP Network Address Translator (NAT) Terminology and NAPT (Network Address Port Translator) technology described in "Considerations, RFC2663".
[0006]
These technologies are basically technologies for translating addresses between one network and another network between two connected networks with different address systems. By combining with the application of private addresses, the efficiency of IP addresses can be improved. It is to realize a practical use.
[0007]
Here, the private address is an IP address that is defined in “Address Allocation for Private Internets, RFC 1918” and that can be used regardless of IANA management. IP addresses “10.xxx”, “172.16.xx”, and “192.168.xx” (where x represents an arbitrary value from 0 to 255) are assigned as private addresses. Note that the IP address assigned to the private address is not used as a global address.
[0008]
Further, “the address systems of the network Na and the network Nb are different” means that the following conditions are satisfied.
[0009]
“Network Na and Network Nb are each a network that forms part of a certain metanetwork (a collection of networks directly or indirectly connected to each other (partial condition 1)”), and
“The network Na and the network Nb each use an address system based on the assignment of an identifier uniquely identifiable in the network to the connected terminal device (partial condition 2), and
“For any terminal device T connected to the network Na,“ the address value A of the terminal device T does not make sense as an identifier representing an address in the address system of the network Nb (such as not being used as an identifier representing an address). (Partial condition 3-1) ”or“ the value A of the address makes sense as an identifier representing an address in the address system of the network Nb (used as an identifier representing an address), but the value of the address in the network Nb It does not know that A is assigned to the terminal device connected to the network Na (partial condition 3-2) "(partial condition 3)".
[0010]
For example, as shown in FIG. 25, there is a meta network in which a network N and a first network N1, a second network N2, a third network N3, and a fourth network N4 are connected as shown in FIG. As for the network address system, the network N has a global address (however, 133.xxx is not allocated in the network N so that it can be used in the first network N1), and the first network N1 has a global address 133. xxx, the second network N2 employs the private address 10.xxx, the third network N3 employs the private address, and the fourth network N4 employs the private address 10.255.xx. The third network N3 and the fourth network N4 is 10.0.xx to 10.254.xx out of one private address 10.xxx Is subnetted to the third network N3, and the remaining 10.255.xx is subnetted to the fourth network N4. Here, in any two networks constituting FIG. 25, partial condition 1 and partial condition 2 are satisfied among the above conditions.
[0011]
The global address system and the private address system both use a part of the 32-bit space value as the address value, but the global address system does not use the address value used in the private address system. For this reason, in the network employing the global address system and the network employing the private address system, the above partial condition 3-1 is satisfied and the above condition is satisfied, so that the address systems are different. That is, the network N and the first network N1 have different address systems from the second network N2, the third network N3, and the fourth network N4.
[0012]
In addition, since the condition 3 does not hold for the network N and the first network N1, the address system is not different. The second network N2 is different from the third network N3 and the fourth network N4 in that the address system is different because the condition 3-1 is not satisfied but the condition 3-2 is satisfied. Since the third network N3 and the fourth network N4 do not satisfy the condition 3, the address systems are not different.
[0013]
FIG. 22 shows the configuration of an existing communication system to which the NAPT technology is applied.
[0014]
As shown in FIG. 22, an existing communication system to which the NAPT technology is applied includes a terminal device T, a NAPT relay device R, a server device S, a global network Ng, and a private network Np. The terminal device T is accessed to the server device S via the NAPT relay device R, and the terminal device T and the NAPT relay device R are connected by a private network Np. On the other hand, the NAPT relay device R and the server device S are connected by a global network Ng.
[0015]
Different address systems are applied to the global network Ng and the private network Np. A global address is assigned to a terminal device connected to the global network Ng, and a private address is assigned to a terminal device connected to the private network Np. The terminal device T includes communication means based on TCP / IP (Transmission Control Protocol / Internet Protocol), and uses the communication means to connect to the server program of the server apparatus S and mount a client program that communicates with the server program. In the information processing device, one private address (referred to as Ap-t) of the private network Np is assigned.
[0016]
The server device S is an information processing device equipped with a communication program based on TCP / IP, which is equipped with a server program that waits for a connection from the client program of the terminal device T using the communication device and communicates with the connected client program. , One global address (assumed to be Ag-s) of the global network Ng is assigned.
[0017]
In the server apparatus S, the server program waits for a connection from the client program at the port identified by the port number Ps. The client program needs to know the port number Ps of the port, and when connecting to the server program, by specifying the port number Ps as the port number of the destination port to the communication means. Connect to the server program and start a communication session with the server program.
[0018]
The NAPT relay device R is a router having an IP packet relay function, which is composed of packet receiving means 1021, 1023, packet transmitting means 1022, 1024, address converting means 1025, 1026, and storage means 1027. One private address (Ap-r) is assigned to the global network Ng, and one global address (Ag-r) is assigned.
[0019]
The storage unit 1027 holds a correspondence management table. The configuration of the correspondence management table is shown in FIG.
[0020]
As shown in FIG. 4, the correspondence management table has an entry including an entry identifier field, a first socket field, a second socket field, and a third socket field. The entry identifier field stores an entry identifier value that uniquely identifies each entry in the correspondence management table in the NAPT relay device R. The first socket field is composed of a pair of private network Np address and port number, and the second socket field and the third socket field are composed of a pair of global network Ng IP address and port number, respectively.
[0021]
The packet receiving unit 1021 receives an IP packet addressed to the global network Ng sent from the private network Np, and passes the received IP packet to the address converting unit 1025.
[0022]
The packet transmission unit 1022 transmits the IP packet passed from the address translation unit 1025 to the global network Ng.
[0023]
The packet receiving unit 1023 receives an IP packet addressed to the private network Np sent from the global network Ng, and passes the received IP packet to the address converting unit 1026.
[0024]
The packet transmission means 1024 sends the IP packet passed from the address translation means 1026 to the private network Np.
[0025]
As shown in FIG. 23, the address conversion unit 1025 includes a correspondence search unit 1251, a packet conversion unit 1252, and a registration unit 1254.
[0026]
The correspondence search unit 1251 receives the IP packet passed from the packet reception unit 1021 to the address conversion unit 1025. When the packet is received from the packet receiving unit 1021, the correspondence search unit 1251 indicates that the value of the first socket field is equal to the set of the source address and source port number of the IP packet from the correspondence management table of the storage unit 1027. And an entry having the same value as the combination of the destination address and the destination port number of the IP packet is retrieved.
[0027]
When the entry is detected by the search, the correspondence search unit 1251 passes the IP packet and the entry identifier stored in the entry identifier field of the entry to the packet conversion unit 1252. When the entry is not detected by the search, the correspondence search unit 1251 passes the IP packet to the registration unit 1254.
[0028]
When the IP packet and the entry identifier are passed, the packet conversion unit 1252 indicates the source address and the source port number of the IP packet in the third socket field of the entry of the correspondence management table identified from the entry identifier. The IP address and the port number are rewritten, and the rewritten IP packet is transferred to the packet transmission unit 1022.
[0029]
Upon receiving the IP packet, the registration unit 1254 generates an unused entry identifier and selects one unused port number. Then, the registration means 1254 uses the entry identifier as the value of the entry identifier field, and sets the combination of the source address and source port number, the destination address and the destination port number of the IP packet as the first socket field and the first address, respectively. 2, an entry is created in which the combination of the IP address of the global network Ng of the NAPT relay device R and the selected port number is the value of the third socket field, and the entry is stored in the storage means 1027. Store in the correspondence management table. Then, the registration unit 1254 passes the IP packet and the entry identifier to the packet conversion unit 1252.
[0030]
As shown in FIG. 24, the address translation unit 1026 includes a correspondence search unit 1261 and a packet translation unit 1262.
[0031]
The correspondence search unit 1261 receives the IP packet passed from the packet receiving unit 1023 to the address converting unit 1026. When the correspondence retrieval unit 1261 receives the IP packet from the packet reception unit 1023, the value of the second socket field is set from the correspondence management table of the storage unit 1027 to the combination of the transmission source address and the transmission source port number of the IP packet. An entry is searched for which is equal and the value of the third socket field is equal to the pair of the destination address and the destination port number of the IP packet.
[0032]
When the entry is detected by the search, the correspondence search unit 1261 passes the IP packet and the entry identifier stored in the entry identifier field of the entry to the packet conversion unit 1262. When the entry is not detected by the search, the correspondence search unit 1261 discards the IP packet because the destination of the IP packet is not known.
[0033]
When the IP packet and the entry identifier are passed, the packet converting unit 1262 receives the IP address of the first socket indicated in the entry of the correspondence management table identified from the entry identifier by specifying the destination address and the destination port number of the IP packet. And the port number value are rewritten, and the rewritten IP packet is transferred to the packet transmission means 1024.
[0034]
Next, the operation of the NAPT technology will be described.
[0035]
Here, first, the terminal device T starts a communication session between the port P-t of the terminal device T and the port P-s of the server device S, so that the port P-t of the terminal device T and the server device S An operation when the first IP packet (referred to as IP packet A) is transmitted to the private network Np between the ports P-s will be described. At this time, in the IP packet A, the destination address is the IP address Ag-s of the server device S, the source address is the IP address Ap-t of the terminal device T, and the destination port in the transport layer protocol header included in the IP packet A The number is Ps, and the source port number is Pt. In the correspondence management table of the storage unit 1027, it is assumed that no entry is registered as an initial state.
[0036]
The IP packet A addressed from the terminal apparatus T to the server apparatus S is received by the packet receiving means 1021 of the NAPT relay apparatus R via the private network Np, and the packet receiving means 1021 sends the IP packet A to the address converting means 1025. hand over.
[0037]
The IP packet A passed to the address translation unit 1025 is received by the correspondence search unit 1251. When the correspondence search means 1251 receives the IP packet A, the correspondence management table of the storage means 1027 indicates that the value of the second socket field is a set of the transmission source address and transmission source port number of the IP packet A [Ap− An entry that is equal to t, P-t] and whose value in the third socket field is equal to the destination address and destination port number pair [Ag-r, P-r] of the IP packet A is searched.
[0038]
In this case, since the entry does not exist in the correspondence management table, the entry is not detected by the search.
[0039]
The correspondence search unit 261 passes the IP packet A to the registration unit 1254 because the entry is not detected in the search.
[0040]
Upon receiving the IP packet A, the registration unit 1254 generates an unused entry identifier and selects one unused port number in the NAPT relay device R (the selected port number is designated as Pr). To do). Then, the registration unit 1254 uses the entry identifier as the value of the entry identifier field, sets the source address and source port number of the IP packet A [Ap-t, Pt], the destination address and the destination port number. [Ag−s, P−s] are values of the first socket field and the second socket field, respectively, and the set of the IP address of the global network Ng of the NAPT relay device R and the selected port number [Ag -R, P-r] is created as the value of the third socket field, and the entry is stored in the correspondence management table of the storage means 1027. Then, the registration unit 1254 passes the IP packet A and the entry identifier to the packet conversion unit 1252.
[0041]
The packet conversion means 1252 receives the IP packet A and the entry identifier, and the correspondence management table for identifying the source address Ap-t and the source port number Pt of the IP packet A from the entry identifier, respectively. The IP address Ag-r and the port number Pr shown in the third socket field of the entry are rewritten, and the rewritten IP packet (referred to as IP packet B) is passed to the packet transmitting means 1022.
[0042]
When the packet transmission means 1022 receives the IP packet B, it transmits the IP packet B to the global network Ng.
[0043]
The IP packet B transmitted from the NAPT relay device R is received by the server device S via the global network Ng. From the contents of the source address, source port number, destination address, and destination port number included in the IP packet B, the server device S uses the port Pr of the device whose IP address is Ag-r. When the IP packet is transmitted in the data communication session, the destination address of the IP packet is Ag-r, and the destination port number Is set to Pr, the source address is set to Ag-s, and the source port number is set to Ps.
[0044]
Thereafter, when the NAPT relay device R receives the IP packet (referred to as IP packet C) of the communication session from the private network Np, it operates in the same manner as the processing of the IP packet A described above. In the processing, the correspondence search unit 1251 determines from the correspondence management table of the storage unit 1027 that the value of the first socket field is a set [Ap-t, P-t] of the source address and source port number of the IP packet C. And an entry having a value of the second socket field equal to the destination address and destination port number pair [Ag-s, P-s] of the IP packet C is detected. The entry identifier of the detected entry is directly passed to the packet conversion unit 1252 without going through the registration unit 1254. The processing after the packet conversion means 1252 is performed in the same manner as in the case of the IP packet A, and the IP packet C is an IP packet having the same source address Ag-r and source port number Pr as the IP packet B. (The converted IP packet is referred to as IP packet D), and the converted IP packet D is sent to the server device S via the global network Ng.
[0045]
Further, as described above, the IP packet (referred to as IP packet E) of the communication session sent from the server apparatus S after processing the IP packet A and IP packet B has a destination address of Ag-r, a destination port, The number is Pr, the transmission source address is Ag-s, and the transmission source port number is Ps. The packet reception unit 1023 of the NAPT relay device R receives the packet via the global network Ng, and the packet reception unit 1023 The IP packet E is passed to the address translation means 1026.
[0046]
The IP packet E passed to the address translation unit 1026 is received by the correspondence search unit 1261. When the IP packet E is passed, the correspondence search means 1261 receives a value of the second socket field from the correspondence management table of the storage means 1027 and sets the combination of the source address and the source port number of the IP packet E [Ag− s, P−s], and an entry in which the value of the third socket field is equal to the destination address and destination port number pair [Ag−r, P−r] of the IP packet E is searched.
[0047]
In this case, since the entry registered at the time of processing the IP packet A exists in the correspondence management table, and the entry corresponds to the entry to be searched, the correspondence search means 1261 indicates the entry identifier of the IP packet E and the entry. The packet is transferred to the packet conversion unit 1262.
[0048]
When the IP packet E and the entry identifier are passed, the packet conversion unit 1262 receives the destination address Ag-r and the destination port number Pr of the IP packet E from the entry of the correspondence management table identified from the entry identifier. The first socket IP address Ap-t and port number P-t are rewritten, and the rewritten IP packet (referred to as IP packet F) is passed to the packet transmission means 1024.
[0049]
When receiving the IP packet F, the packet transmission means 1024 sends the IP packet F to the private network Np.
[0050]
The IP packet F sent from the NAPT relay device R is received by the terminal device T via the private network Np.
[0051]
As described above, in the existing communication system to which the NAPT technology is applied, the NAPT relay device R includes a pair of a socket configured with a private address and port number and a socket configured with a global address and port number. One communication session to be identified is associated with a set of one global address and port number, and the IP address and port number on the private network Np side at the time of relaying, and the global network Ng associated with the communication session By mutually converting the IP address and the port number on the side, communication by IP between a device connected to the private network Np having a different address system and a device connected to the global network Ng is made possible. The present technology can also be applied to a communication system having a configuration in which a plurality of private networks using the same private address system are connected to one global network. By connecting each private network and the global network with a NAPT relay device, communication between the terminal device connected to each private network and the server device connected to the global network can be realized. Therefore, it is possible to increase the number of IP addresses assigned to the terminal device by increasing the number of private networks connected by the NAPT relay device.
[0052]
[Problems to be solved by the invention]
The first problem is that communication cannot be started from the server device when communicating between the server device connected to the global network and the terminal device connected to the private network.
[0053]
The reason is that when communication is started from the server device, the server device must first know the IP address of the terminal device from the name of the terminal device, but the address cannot be resolved at this time.
[0054]
The second problem is that communication is not possible between terminal devices connected to different private networks.
[0055]
The reason is that, similarly to the reason for the first problem described above, in the terminal device that starts communication, the address of the terminal device that is the communication partner cannot be resolved.
An object of the present invention is to provide a terminal device, a relay device, a communication method, and the like that solve such problems.
[0056]
[Means for Solving the Problems]
In the present invention, the address of the terminal device 1-x (x = 1, 2,..., N) connected to the first network (the private network 4 in the example of FIG. 1) in advance in the storage means 27 and the terminal device. A port number corresponding to the service provided by 1-x is registered. When the relay device 2 receives a packet for starting data communication from the terminal device 3 connected to a second network (global network 5 in the example of FIG. 1) having a different address system from the first network, the address conversion means 26 Searches the storage means 27 for the address of the terminal device in which the port number equal to the destination port number included in the packet is registered, converts the destination address of the packet into the searched address, and sends it to the first network. .
[0057]
By adopting such a configuration, when communicating between a server device connected to the second network and a terminal device connected to the first network, it is possible to start communication from the server device, Communication between terminal devices connected to networks with different address systems is made possible, and the first and second problems are solved.
[0058]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described in detail with reference to the drawings.
[0059]
FIG. 1 shows a first embodiment relating to a terminal device, a relay device, and a communication method thereof according to the present invention.
[0060]
In the conventional technology, when a network using a global address system (global network) and a network using a private address system (private network) are connected by a relay device, a private network is assigned to one global address in the global network. The first terminal device connected to the global network cannot uniquely identify the address of the second terminal device connected to the private network. Data communication from one terminal device to the second terminal device could not be started. In the present embodiment, in addition to the configuration of the existing communication system, a processing terminal registration table is newly introduced as a table to be stored in the storage unit (storage unit 1027) of the relay apparatus, and one address conversion unit (existing Registration search means and registration means are introduced into the address conversion means 1026 in the technology). A service that can start data communication from the first terminal device to the second terminal device is determined in advance, and a port number that is one of service identifiers corresponding to the service and the second terminal The correspondence with the address of the device is stored in the processing terminal registration table, and when the relay device receives a packet for starting a communication session from the first terminal device to the second terminal device, the registration search means By searching the address of the second terminal device corresponding to the destination port number of the packet from the processing terminal registration table and setting the destination of the packet as the searched second terminal device, the first terminal device The data communication to the second terminal device can be started. Further, at this time, the registration means registers the correspondence of these sockets in the correspondence management table in the same manner as the existing technology, so that the bidirectional packets of the communication session thereafter can be relayed in the same manner. To do.
[0061]
The configuration of the first embodiment of the present invention is shown in FIG. 1, FIG. 2, FIG. 3, and FIG.
[0062]
As shown in FIG. 1, the first embodiment of the present invention includes a plurality of terminal devices (terminal device 1-1, terminal device 1-2,..., Terminal device 1-n), relay device 2 Terminal device 3 and networks 4 and 5, terminal device 1 -x (x = 1, 2,..., N, and so on) and relay device 2 are connected via network 4 and relayed. The device 2 and the terminal device 3 are connected via the network 5.
[0063]
The networks 4 and 5 are networks to which different address systems are applied.
[0064]
The network 4 is a network configured by IP or other technology, and is a network that provides a data transfer service such as an IP network, an ISDN network, and a mobile communication network. In the network 4, a packet carrying user data and control information is transferred between the terminal device 1-x and the relay device 2.
[0065]
The network 5 is an IP network to which a global address is applied. In the network 5, an address resolution inquiry message that makes an inquiry for address resolution between the relay device 2 and the terminal device 3, an address resolution response message that responds to the address resolution inquiry, and other control information and user data IP packets carrying are forwarded.
[0066]
The terminal device 1-x is an information processing device having a communication function that can be used in the network 4, and is equipped with a communication program that communicates with the communication program of the terminal device 3 using the communication function. 4 address (referred to as A1-x) is assigned. The terminal device name is composed of information about the network to which the terminal device is connected and an identifier that can be uniquely identified within the network, as in FQDN (Fully Qualified Domain Name) format. The terminal device program or user is used to identify the terminal device.
[0067]
The terminal device 3 is a terminal device that is used in the existing Internet, has a communication function by TCP / IP, and is equipped with a communication program that communicates with the communication program of the terminal device 1-x using the communication function. In the information processing device, a terminal device name and one address (referred to as A2-1) of the network 5 are assigned. Similarly to the terminal device 1-x, the terminal device name is composed of information on the network to which the terminal device is connected and an identifier that can be uniquely identified in the network, as in the FQDN format. It is used for programs of other terminal devices and users to identify the terminal devices. When the terminal device 3 starts communication with another terminal device, the terminal device 3 receives the IP address of the other terminal device from the name of the other terminal device (or the destination of the IP packet to be sent to the other terminal device). Address resolution means for inquiring about the IP address of the device. The address resolution means is realized by a DNS (Domain Name System) technique described in RFC 1035 “DOMAIN NAMES-IMPLEMENTATION AND SPECIFICATION”.
[0068]
The relay device 2 is composed of packet receiving means 21 and 23, packet transmitting means 22 and 24, address converting means 25 and 26, storage means 27, and address inquiry response means 28, and one address (A1-r and And one IP address (A2-2) of the network 5 is assigned.
[0069]
The storage means 27 holds a processing terminal registration table and a correspondence management table. The configuration of the processing terminal registration table and the correspondence management table is shown in FIG.
[0070]
As shown in FIG. 4, the processing terminal registration table includes an entry identifier field that stores a value of a first entry identifier that uniquely identifies an entry in the processing terminal registration table in the relay device 2, and an address field that stores an address of the network 4. And a port number field pair for storing the port number as an entry. In the processing terminal registration table, a terminal device that processes a service to be provided to the terminal device 3 is determined in advance, the address of the terminal device that processes the service is in the address field, and the port number corresponding to the service is the port number. The entry set in the field is stored. For example, the terminal device that provides the FTP service to the terminal device 3 is determined as the terminal device 1-1, the address A1-1 of the terminal device 1-1 in the processing terminal registration table, and the port number corresponding to the FTP service Set 20 groups.
[0071]
The correspondence management table has an entry including an entry identifier field, a first socket field, a second socket field, and a third socket field. The entry identifier field stores a value of a second entry identifier that uniquely identifies each entry in the correspondence management table in the relay device 2. The first socket field consists of a set of the network 4 address and port number, and the second socket field and the third socket field consist of a set of the network 5 IP address and port number, respectively.
[0072]
The packet receiving unit 21 receives a packet addressed to the network 5 sent from the network 4 and passes the received packet to the address converting unit 25.
[0073]
The packet transmission unit 22 transmits the IP packet passed from the address conversion unit 25 to the network 5.
[0074]
The packet receiving unit 23 receives an IP packet addressed to the network 4 sent from the network 5 and passes the received IP packet to the address converting unit 26.
[0075]
The packet transmission unit 24 transmits the packet passed from the address conversion unit 26 to the network 4.
[0076]
As shown in FIG. 2, the address conversion unit 25 includes a correspondence search unit 251, a packet conversion unit 252, and a registration unit 254.
[0077]
The correspondence search unit 251 receives the packet passed from the packet receiving unit 21 to the address converting unit 25. When the correspondence retrieval unit 251 receives the packet from the packet reception unit 21, the value of the first socket field is equal to the combination of the transmission source address and the transmission source port number of the packet from the correspondence management table of the storage unit 27. In addition, an entry having a value equal to the combination of the destination address and the destination port number of the packet is retrieved.
[0078]
When the entry is detected by the search, the correspondence search unit 251 passes the packet and the second entry identifier stored in the entry identifier field of the entry to the packet conversion unit 252. If the entry is not detected by the search, the correspondence search unit 251 passes the packet to the registration unit 254.
[0079]
When the packet conversion unit 252 receives the packet and the second entry identifier, the packet conversion unit 252 converts the packet into an IP packet, and the source address and source port number of the IP packet are identified from the second entry identifier. The IP address and port number values shown in the third socket field of the corresponding management table entry are rewritten, and the rewritten IP packet is transferred to the packet transmitting means 22.
[0080]
When receiving the packet, the registration unit 254 generates an unused second entry identifier and selects one unused port number. Then, the registration unit 254 uses the second entry identifier as the value of the entry identifier field, and sets the combination of the transmission source address, the transmission source port number, the destination address, and the destination port number of the packet in the first socket field. And the second socket field value, an entry is created in which the combination of the IP address of the network 5 of the relay device 2 and the selected port number is the third socket field value. Store in the correspondence management table. Then, the registration unit 254 passes the packet and the second entry identifier to the packet conversion unit 252.
[0081]
As shown in FIG. 3, the address conversion unit 26 includes a correspondence search unit 261, a packet conversion unit 262, a registration search unit 263, and a registration unit 264.
[0082]
The correspondence search unit 261 receives the IP packet passed from the packet receiving unit 23 to the address converting unit 26. When the correspondence retrieval unit 261 receives the IP packet from the packet reception unit 23, the value of the second socket field is set from the correspondence management table of the storage unit 27 to the combination of the transmission source address and the transmission source port number of the IP packet. An entry is searched for which is equal and the value of the third socket field is equal to the pair of the destination address and the destination port number of the IP packet.
[0083]
When the entry is detected by the search, the correspondence search unit 261 passes the IP packet and the second entry identifier stored in the entry identifier field of the entry to the packet conversion unit 262. When the entry is not detected by the search, the correspondence search unit 261 passes the IP packet to the registration search unit 263.
[0084]
When the IP packet and the second entry identifier are passed, the packet conversion unit 262 converts the IP packet into a packet of the network 4, and identifies the destination address and the destination port number of the packet from the second entry identifier, respectively. The correspondence management table entry is rewritten with the IP address and port number values of the first socket, and the rewritten packet is transferred to the packet transmitting means 24.
[0085]
When receiving the IP packet, the registration search means 263 refers to the processing terminal registration table and searches for an entry having the value of the destination port number of the IP packet as the value of the port number field.
[0086]
If the entry is not detected from the processing terminal registration table by the search, the registration search means 263 discards the IP packet and ends the processing.
[0087]
When the entry is detected from the processing terminal registration table by the search, the registration search unit 263 passes the first entry identifier stored in the entry identifier field of the entry and the IP packet to the registration unit 264.
[0088]
When the first entry identifier and the IP packet are passed, the registration means 264 receives the address and port number stored in the address field of the entry in the processing terminal registration table of the storage means 27 identified by the first entry identifier. The port number stored in the field is read, an unused second entry identifier is generated, the second entry identifier is set as the value of the entry identifier field, and the set of the address and the port number is set to the first The socket field value of the IP packet, a pair of the source address and source port number of the IP packet as a second socket field, and a pair of the destination address and destination port number of the IP packet as a value of the third socket field. The entry is created and stored in the correspondence management table of the storage means 27. Then, the registration unit 264 passes the IP packet and the second entry identifier to the packet conversion unit 262.
[0089]
In response to the address resolution inquiry message sent from the network 5, the address inquiry response resolution means 28 uses the name of the terminal device 1 -x connected by the network 4 as the name of the terminal device inquired by the address resolution inquiry message. If there is, an address resolution response message is sent to the sender of the address resolution query message as a response to the IP address A2-2 of the network 5 assigned to the relay device 2 as a response to the address resolution query message.
[0090]
Here, the structure of the message used in the present embodiment will be described with reference to FIG. Note that the structure of each message shown in FIG. 5 is schematically expressed by extracting only the fields related to the present invention.
[0091]
The IP packet used in the network 5 includes a source address, a destination address, a source port number, a destination port number, various control information, and user data. An example of the structure of the IP packet is shown in FIG. Referring to (a) of FIG. 5, the IP packet includes an IP header, a transport header, and a data part. As the transport header, either a TCP header, a UDP header, or a header of another transport protocol can be used. The header of which transport protocol is used is determined by the protocol identifier field of the IP header. Instructed. In the IP packet, the source address and the destination address are included in the IP header, and the source port number and the destination port number are included in the transport header. Various control information and user data are included in the data part.
[0092]
The address resolution inquiry message includes the name of the terminal device to be inquired, and the address resolution response message includes the address of the terminal device having the name included in the responding address resolution inquiry message. FIG. 5 shows the structure of each message when address resolution is realized by the above DNS. Referring to FIG. 5, both the address resolution inquiry message and the address resolution response message have an IP header and a transport header like the IP packet, but differ in that the data part in the IP packet is a DNS message. The difference between the IP packet and other messages is that in the address resolution inquiry message and the address resolution request message, either the source port number or the destination port number has a value 53 representing the DNS service, and the IP packet is transmitted. The source port number and the destination port number are both identified by other than 53. Further, the address resolution inquiry message and the address resolution response message are identified by the value of the query / response flag in the DNS message (if the value of the query / response flag is 0, it is an address resolution query message, and the value is 1). Is an address resolution response message).
[0093]
The name of the terminal device inquired by address resolution is stored in the name field in the DNS message of the address resolution inquiry message, and the address of the terminal device of the inquired name is stored in the address field in the DNS message of the address resolution response message.
[0094]
Each time the terminal device 3 creates an address resolution inquiry message, the terminal device 3 generates an identifier that can be uniquely identified by the terminal device 3, and generates the identifier in the identifier field in the DNS message included in the created address resolution inquiry message. Is stored. When the relay device 2 creates an address resolution response message in response to the received address resolution query message, the relay device 2 extracts the identifier stored in the identifier field in the DNS message of the address resolution query message, The identifier is stored in the identifier field in the DNS message. Thereby, the terminal device 3 can identify the address inquiry request message to which the address inquiry response message responds by referring to the value of the identifier field in the DNS message of the received address inquiry response message.
[0095]
A packet used in the network 4 includes a source address, a destination address, a source port number, a destination port number, various control information, and user data. If the network 4 is a network configured by IP, it can be configured as shown in FIG. Since the configuration of the packet used in the network 4 depends on the type of protocol technology used in the network 4, it cannot be uniquely expressed. For example, it can be expressed as shown in FIG.
[0096]
Although not shown here, the terminal device 1-x, the relay device 2, and the terminal device 3 each receive all messages, and the message type from the message type information included in the message type field of each received message. And a message distribution means for passing the message type to the means for processing the corresponding message type. For example, the relay device 2 receives two types of messages, that is, an IP packet and an address resolution inquiry message from the network 5, which are received by the message distribution unit of the relay device 2, and the message distribution unit transmits the received message to the IP If it is a packet, the IP packet is passed to the packet receiving means 23, and if the received message is an address resolution inquiry message, the address resolution inquiry message is passed to the address inquiry response means 28. Such message distribution means is necessary for the implementation of the present invention. However, since the message distribution means is not an essential component for realizing the technical features of the embodiment of the present invention, the description will be simplified. In order to clarify the technical features of the embodiment of the present invention, illustration and description of the message distribution means are omitted.
[0097]
Also, in other embodiments of the invention described below, the message distribution unit is also necessary, but the illustration and description of the message distribution unit are omitted for the same reason.
[0098]
Next, the operation of the first embodiment of the present invention will be described with reference to FIGS. 1, 2, 3, 4, and 6. FIG.
[0099]
There are two types of data communication executed in the first embodiment of the present invention: a case where the terminal device 1-x starts a data communication session and a case where the terminal device 3 starts.
[0100]
Since the case where the terminal device 1-x starts the data communication session is performed in the same manner as the NAPT technology that is an existing technology, description of the operation is omitted, and here, the terminal device 3 starts the data communication session. The operation in this case will be described.
[0101]
In the network 4, the terminal device that processes the service corresponding to the port number P1 is defined as the terminal device 1-x, and the correspondence between the address A1-x and the port number P1 is stored in the processing terminal registration table in the relay device. The case where the terminal device 3 starts data communication from the port having the port number P2 to the port having the port number P1 of the terminal device 1-x will be described.
[0102]
When the terminal device 3 starts data communication with the terminal device 1-x, first, address resolution is performed from the name of the terminal device 1-x. This is started when the terminal device 3 transmits an address resolution inquiry message including the name of the terminal device 1-x as a resolution target device name to the network 5 (step A1 in FIG. 6).
[0103]
The address resolution inquiry message is received by the address inquiry response means 28 of the relay device 2, and the address inquiry response means 28 relays since the device inquired by the address resolution inquiry message is the terminal device 1-x. An address resolution response message with the IP address A2-2 in the network 5 of the device 2 as a response to the inquiry is created and transmitted to the network 5 (step A2).
[0104]
The address resolution response message is received by the terminal device 3, and the terminal device 3 knows from the contents of the address resolution response message that the destination IP address of the IP packet addressed to the terminal device 1-x is A2-2.
[0105]
Next, the terminal device 3 generates an IP packet including data addressed to the terminal device 1-x and transmits it to the network 5 (step A3). The IP packet has a destination address of A2-2, a source address of A2-1, a destination port number P1, and a source port number of P2.
[0106]
The IP packet is received by the packet receiving unit 23, and the packet receiving unit 23 passes the IP packet to the address converting unit 26.
[0107]
The IP packet transferred to the address translation unit 26 is received by the correspondence search unit 261. When the correspondence search unit 261 receives the IP packet, the values of the second socket field and the third socket field are determined from the correspondence management table of the storage unit 27, and the source address and source port number of the IP packet, respectively. Entry [A2-1, P2] and an entry having a value equal to the destination address and destination port number set [A2-2, P1] of the IP packet are searched.
[0108]
In this case, data communication between the port with the port number P2 of the terminal device 3 and the port with the port number P1 of the terminal device 1-x has not been performed in the past, and the entry does not exist in the correspondence management table. The entry is not detected by the search.
[0109]
The correspondence search unit 261 passes the IP packet to the registration search unit 263 because the entry is not detected in the search.
[0110]
When the IP packet is passed, the registration search means 263 refers to the processing terminal registration table and searches for an entry having the destination port number value P1 of the IP packet as the value of the port number field.
[0111]
In this case, as described above, there is an entry with the preset address A1-x and the port number P1, and the entry is detected by the search.
[0112]
Since the registration search unit 263 has detected the entry by the search, the registration search unit 263 passes the first entry identifier and the IP packet stored in the entry identifier field of the entry to the registration unit 264.
[0113]
When the registration means 264 receives the first entry identifier and the IP packet, the registration means 264 receives the address stored in the address field of the entry in the processing terminal registration table of the storage means 27 identified by the first entry identifier. The port number stored in the port number field is read, an unused second entry identifier is generated, the second entry identifier is set as the value of the entry identifier field, and the set of the address and the port number [ A1-x, P1] is the value of the first socket field, the pair [A2-1, P2] of the source address and source port number of the IP packet is the value of the second socket field, and the IP packet Create an entry whose destination socket number and destination port number pair [A2-2, P1] is the value of the third socket field; Storing an entry in the correspondence management table of the storage unit 27. Then, the registration unit 264 passes the IP packet and the second entry identifier to the packet conversion unit 262.
[0114]
When the IP packet and the second entry identifier are passed, the packet conversion unit 262 converts the IP packet into a packet of the network 4, and sets the destination address and the destination port number of the packet to the second entry identifier, respectively. Are rewritten to the IP address and port number values A1-x and P1 shown in the first socket field of the entry of the correspondence management table of the storage means 27 identified by the data, and the rewritten packet is transferred to the packet transmission means 24.
[0115]
When the packet transmitting means 24 receives the packet, it sends the packet to the network 4 and the packet is received by the terminal device 1-x (step A4).
[0116]
Thereafter, the IP packet addressed to the port number P1 of the terminal device 1-x sent from the terminal device 3 to the network 5 (the destination address is A2-2, the source address is A2-1, the destination port number is P1, the source port number P2) is similarly received by the packet receiving means 23 of the relay device 2, and the IP packet is passed to the correspondence search means 261 by the packet receiving means 23, but the correspondence management table of the storage means 27 contains the second socket. The value of the field is equal to the pair [P2-1, P2] of the source address and source port number of the IP packet, and the value of the third socket field is the pair of the destination address and destination port number of the IP packet Since there is an entry equal to [P2-2, P1], the correspondence search means 261 detects the entry by searching the correspondence management table. The IP packet and the second entry identifier of the entry are passed to the packet conversion unit 262. The packet conversion unit 262 converts the IP packet into a packet of the network 4 addressed to the port number P1 of the terminal device 1-x. Is transmitted to the terminal device 1-x via the network 4 by the packet transmission means 24.
[0117]
Similarly, after step A4, packets addressed to the port number P2 of the terminal device 3 sent from the port number P1 of the terminal device 1-x to the network 4 (the destination address is A2-1, the source address is A1- x, the destination port number is P2, and the source port number is P1), the destination address is A2-1 and the source address is A2 through the packet receiving unit 21, the address converting unit 25, and the packet transmitting unit 22 in the relay apparatus 2. -2, the destination port number is converted to an IP packet with P2 and the transmission source port number is P1, and the converted IP packet is transmitted to the terminal device 3 via the network 5.
[0118]
As described above, when relaying an IP packet addressed to the network 4 from the network 5, the relay device 2 is a terminal device connected to the network 4 that processes the port number registered in advance and the IP packet addressed to the port number. From the terminal device of the network 5 to which the address system of the global address is applied by referring to the address correspondence, determining the terminal device that is the destination of the IP packet, and converting the IP packet into a packet addressed to the terminal device Communication to the terminal device of the network 4 using a different address system becomes possible.
[0119]
In the embodiment of the present invention, the case where there is one terminal device connected to the network 5 has been described. However, the present invention can be similarly implemented even when there are a plurality of terminal devices connected to the network 5.
[0120]
In the embodiment of the present invention, a terminal device (terminal device 1-x) connected to a network different from the global network (referred to as a non-global network), and a terminal device connected to the global network (terminal device 3) In the communication system in which a plurality of non-global networks are each connected to a network having a different address system by the relay device according to the embodiment of the present invention, any communication connected to any non-global network is described. Communication between the terminal devices is also realized in the same manner. That is, in the communication system shown in FIG. 7, communication between arbitrary terminal devices is possible. This is because the terminal device (terminal device A) connected to the i-th non-global network (where i is any one of 1, 2,..., N) to the j-th non-global network (where j is When transmitting a packet for starting a communication session to a terminal device (terminal device B) connected to any one of 1, 2,..., N and j ≠ i), the i-th relay This is because the operations of the device with respect to the j-th relay device and the terminal device B are equal to those of the terminal device 3 in the embodiment of the present invention. However, when the relay network is a non-global network, the address system of the relay network must be different from both the address system of the i-th non-global network and the address system of the j-th non-global network.
[0121]
Further, in the embodiment of the present invention, the case where the terminal device 1-x is the terminal device on the other side that knows the name when the terminal device 3 starts data communication has been described. Only the name of the relay device 2 may be known, and address resolution may be performed by designating the name of the relay device 2.
[0122]
Next, a second embodiment of the present invention will be described with reference to FIG.
[0123]
Referring to FIG. 8, in the second embodiment of the present invention, the terminal device 1-x has a power supply operation monitoring in addition to the configuration of the terminal device 1-x in the first embodiment shown in FIG. Means 11, registration request transmission means 12, deletion request transmission means 13, operation confirmation response means 14, and storage means 15, and the relay apparatus 2 is the relay apparatus in the first embodiment shown in FIG. In addition to the configuration of 2, the registration request receiving unit 291, the deletion request receiving unit 292, and the operation check request unit 293 are different. The configuration of the address conversion unit 26 is also the same as the configuration of the address conversion unit 26 in the first embodiment shown in FIG.
[0124]
The storage means 15 stores a provided service list.
[0125]
The provided service list is a list including port numbers corresponding to services provided to the terminal device 3 by the terminal device 1-x, and is set in advance by a user of the terminal device 1-x.
[0126]
The power supply operation monitoring means 11 monitors the power supply operation of the terminal device 1-x by the user. When the power supply ON operation is detected, the power supply operation monitoring means 11 notifies the registration request transmitting means 12 of the power supply ON. Is sent to the deletion request transmission means 13.
[0127]
When the registration request transmission unit 12 is notified of the power ON, the registration request transmission unit 12 refers to the provided service list in the storage unit 15 and the port number list including all the port numbers set in the provided service list and the terminal device 1-x. A registration request message including the address is generated, and the registration request message is transmitted to the relay apparatus 2 via the network 4.
[0128]
When the power-off notification is sent, the deletion request transmission unit 13 creates a deletion request message including the address of the terminal device 1 -x, and transmits the deletion request message to the relay device 2 via the network 4.
[0129]
The operation confirmation response means 14 receives the operation confirmation request message transmitted from the relay device 2 via the network 4 and, when receiving the operation confirmation request message, responds to the operation confirmation request message to the relay device 2. An operation confirmation response message is created, and the operation confirmation response message is transmitted to the relay apparatus 2 via the network 4.
[0130]
The registration request receiving unit 291 receives a registration request message transmitted from the terminal device 1-x via the network 4, and upon receiving the registration request message, generates an unused first entry identifier, An entry is created in which the field value is the first entry identifier, the address field value is the address included in the registration request message, and the port number field value is the port number list included in the registration request message. The entry is stored in the processing terminal registration table of the storage unit 27, and the operation check request unit 293 is notified of the activation of the terminal device corresponding to the address.
[0131]
The deletion request receiving unit 292 receives the deletion request message transmitted from the terminal device 1-x via the network 4, and when receiving the deletion request message, the value of the address field is read from the processing terminal registration table of the storage unit 27. Deletes all entries equal to the address included in the deletion request message, and notifies the operation check request means 293 of the termination of the terminal device corresponding to the address.
[0132]
The operation confirmation request unit 293 creates an operation confirmation request message, transmits the operation confirmation request message to the terminal device 1-x via the network 4, and responds to the operation confirmation request message from the terminal device 1-x. Wait for receipt of operation confirmation response message. Thereafter, if the operation confirmation response message is successfully received, the operation confirmation request unit 293 confirms that the terminal device 1-x is operating. After that, if reception of the operation confirmation response message fails, the operation confirmation requesting unit 293 considers that the terminal device 1-x has stopped, and the value of the address field is determined from the processing terminal registration table of the storage unit 27. Delete all entries whose address is equal to the address of the terminal device 1-x.
[0133]
The operation confirmation requesting unit 293 activates a timer immediately after transmission of the corresponding operation confirmation request message as a method for determining the reception failure of the operation confirmation response message, and sets the operation confirmation response message as a failure when the timer expires. A method or the like can be used. In addition, the operation check request unit 293 notifies the end of the terminal device 1-x after the activation of the terminal device 1-x is notified of the creation and transmission of the operation check request message to the terminal device 1-x. Or until it fails to receive the operation confirmation response message from the terminal device 1-x.
[0134]
Next, the operation of the second embodiment of the present invention will be described with reference to FIG. 8, FIG. 9, and FIG.
[0135]
When the user of the terminal device 1-x turns on the power of the terminal device 1-x that is stopped (step B1 in FIG. 9), the power operation monitoring means 11 detects an operation to turn on the power. Then, the power-on is notified to the registration request transmission means 12.
[0136]
The registration request transmitting unit 12 refers to the provided service list in the storage unit 15 and sends a registration request message including the port number list including all the port numbers set in the provided service list and the address of the terminal device 1-x. The registration request message is created and transmitted to the relay device 2 via the network 4 (step B2).
[0137]
The registration request message transmitted to the relay apparatus 2 is received by the registration request receiving unit 291. The registration request receiving unit 291 generates an unused first entry identifier, and the port included in the registration request message. From the number list and address, an entry is created in which the value of the entry identifier field is the first entry identifier, the value of the address field is the address, and the value of the port number field is the port number list. The data is stored in the processing terminal registration table of the storage unit 27, and further, the operation check request unit 293 is notified of the activation of the terminal device 1-x.
[0138]
At this time, the relay device 2 can relay the start of data communication from the terminal device 3 to the registered port number of the terminal device 1-x.
[0139]
When notified of the activation of the terminal device 1-x, the operation confirmation requesting unit 293 starts a confirmation operation for the terminal device 1-x (step B3). In other words, the operation confirmation request unit 293 creates an operation confirmation request message and transmits the operation confirmation request message to the terminal device 1-x via the network 4 (step B4).
[0140]
The operation confirmation request message is received by the operation confirmation response unit 14 of the terminal device 1-x. The operation confirmation response unit 14 creates an operation confirmation response message as a response to the operation confirmation request message, and the operation confirmation response message Is transmitted to the relay device 2 via the network 4 (step B5).
[0141]
The operation confirmation response message is received by the operation confirmation requesting means 293, and the operation confirmation requesting means 293 confirms that the terminal device 1-x is operating upon receipt of the operation confirmation response message (step B6).
[0142]
Thereafter, the operation confirmation requesting unit 293 continues to confirm that the terminal device 1-x is operating by periodically executing the steps B4 to B6.
[0143]
Thereafter, when the user of the terminal device 1-x turns off the power of the terminal device 1-x (step B7), the power operation monitoring means 11 detects an operation of turning off the power and deletes the power off. The request transmission means 13 is notified.
[0144]
The deletion request transmission means 13 creates a deletion request message including the address of the terminal device 1-x, and transmits the deletion request message to the relay device 2 via the network 4 (step B8).
[0145]
The delete request message transmitted to the relay device 2 is received by the delete request receiving means 292. The delete request receiving means 292 includes the value of the address field in the delete request message from the processing terminal registration table of the storage device 27. All entries equal to the address are deleted, and the operation confirmation requesting means 293 is notified of the termination of the terminal device 1-x.
[0146]
When the end of the terminal device 1-x is notified, the operation check requesting unit 293 stops the transmission of the operation check request message to the terminal device 1-x that has been periodically performed until then, and the terminal device 1-x The confirmation operation is terminated (step B9).
[0147]
The operation confirmation requesting unit 293 is a timer for waiting for reception of an operation confirmation response message that is a response to the operation confirmation request message immediately after the operation confirmation request message is transmitted during execution of the confirmation operation to the terminal device 1-x. This is because when the normal operation of the terminal device 1-x is stopped due to a malfunction or abnormal stop of the control system of the terminal device 1-x, the relay device 2 detects the stop of the operation of the terminal device 1-x. Used to do. That is, in the confirmation operation by the operation confirmation request unit 293 performed after the normal operation of the terminal device 1-x is stopped (step C1 in FIG. 10), the operation confirmation request unit 293 transmits an operation confirmation request message ( In step C2), a timer is started (step C3), but the timer expires without receiving an operation confirmation response message as a response to the operation confirmation request message (step C4). At this time, the operation confirmation request unit 293 detects that the operation of the terminal device 1-x has stopped (step C5), and the value of the address field is the value of the terminal device 1-x from the processing terminal registration table of the storage unit 27. All entries equal to the address are deleted, and the confirmation operation to the terminal device 1-x is terminated (step C6).
[0148]
When receiving an IP packet from the network 5, the relay device 2 operates in the same manner as in the above-described first embodiment.
[0149]
As described above, in the present embodiment, the provided service list set in the terminal device 1-x is registered in the relay device 2 when the terminal device 1-x is activated, and is transmitted from the relay device 2 when the terminal device 1-x is terminated. In order to delete the information, the information depending on the setting of the terminal device 1-x can be automatically registered in the relay device 2, and when the terminal device 1-x operates, the IP packet from the network 5 is transmitted to the terminal device 1- However, when the terminal device 1-x is not operating, it is possible not to relay the IP packet from the network 5 to the terminal device 1-x.
[0150]
In the present embodiment, when the terminal device 1-x is powered on, the relay device 2 is notified of the set of port numbers constituting the provided service list stored in the storage means 15, and each port number of the set of port numbers is stored. This is stored in the processing terminal registration table of the means 27. This is because when the terminal device 1-x is operating, the user changes the contents of the provided service list stored in the storage means 15, and is changed at that time. The relay device 2 is notified of the set of port numbers constituting the provided service list, and all entries whose address field value stored in the processing terminal registration table of the storage means 27 is the address of the terminal device 1-x are deleted. Each port number of the set of port numbers may be stored in the processing terminal registration table of the storage means 27.
[0151]
In the embodiment of the present invention, the case where there is one terminal device connected to the network 5 has been described. However, the present invention can be similarly implemented even when there are a plurality of terminal devices connected to the network 5.
[0152]
In the embodiment of the present invention, a terminal device (terminal device 1-x) connected to a network different from the global network (referred to as a non-global network), and a terminal device connected to the global network (terminal device 3) In the communication system in which a plurality of non-global networks are each connected to a network having a different address system by the relay device according to the embodiment of the present invention, any communication connected to any non-global network is described. Communication between the terminal devices is also realized in the same manner. That is, in the communication system shown in FIG. 7, communication between arbitrary terminal devices is possible. This is because the terminal device (terminal device A) connected to the i-th non-global network (where i is any one of 1, 2,..., N) to the j-th non-global network (where j is When transmitting a packet for starting a communication session to a terminal device (terminal device B) connected to any one of 1, 2,..., N and j ≠ i), the i-th relay This is because the operations of the device with respect to the j-th relay device and the terminal device B are equal to those of the terminal device 3 in the embodiment of the present invention. However, when the relay network is a non-global network, the address system of the relay network must be different from both the address system of the i-th non-global network and the address system of the j-th non-global network.
[0153]
Further, in the embodiment of the present invention, the case where the terminal device 1-x is the terminal device on the other side that knows the name when the terminal device 3 starts data communication has been described. Only the name of the relay device 2 may be known, and address resolution may be performed by designating the name of the relay device 2.
[0154]
Next, a third embodiment of the present invention will be described with reference to FIGS.
[0155]
Referring to FIG. 11, in the third embodiment of the present invention, terminal device 1-x transmits capability information in addition to the configuration of terminal device 1-x in the second embodiment shown in FIG. Means 16 and the relay device 2 has capability information receiving means 294 in addition to the configuration of the relay device 2 in the second embodiment shown in FIG. 8, and referring to FIG. The configuration of the conversion device 26 is different in that it includes destination selection means 265 in addition to the configuration of the address conversion device 26 in the first embodiment shown in FIG. Further, the processing capability information of the terminal device 1-x is stored in the storage unit 15, and a processing capability information field is added to the entry of the processing terminal registration table stored in the storage unit 27 as shown in FIG. .
[0156]
The processing capability information of the terminal device 1-x stored in the storage unit 15 is information relating to the processing capability of the terminal device 1-x. For example, the processing capability of the CPU and various media such as text, sound, and image are stored. There are things related to processing and display capabilities.
[0157]
In the processing terminal registration table stored in the storage unit 27, the field configuration constituting the entry is the terminal device 1 in addition to the field configuration in the first embodiment and the second embodiment described above. -It has a processing capability information field for storing processing capability information of x, the address of the terminal device 1-x, the port number corresponding to the service provided by the terminal device 1-x, and the processing capability information of the terminal device 1-x The point of managing correspondence is different.
[0158]
When the power supply operation monitoring unit 11 is notified of the power ON, the capability information transmission unit 16 reads the processing capability information of the terminal device 1-x stored in the storage unit 15, and the processing capability information and the terminal device 1- A capability notification message including the address of x is created, and the capability notification message is transmitted to the relay apparatus 2.
[0159]
The capability information receiving unit 294 receives the capability notification message transmitted from the terminal device 1-x, and the terminal device 1-x whose address field value is included in the capability notification message from the processing terminal registration table of the storage unit 27. An equal entry is searched, and the correspondence of the processing capability information included in the capability notification message is stored in the processing capability information field of the entry.
[0160]
When one or more first entry identifiers and one IP packet are notified from the registration search unit 263, the destination selection unit 265 receives the one notified from the processing terminal registration table of the storage unit 27, or Then, an entry identified by a plurality of first entry identifiers is read, and further, the processing capability information of each terminal device is read from the read entry, and the read processing capability information is compared to determine an optimum terminal device. The registration unit 264 is notified of the selected address / port number pair and the IP packet.
[0161]
As a method of selecting one terminal device from the processing capability information of a plurality of terminal devices, there is a method of selecting a terminal device having the highest processing capacity.
[0162]
Next, the operation of the third exemplary embodiment of the present invention will be described with reference to FIG.
[0163]
When the user of the terminal device 1-x turns off the power of the terminal device 1-x (step D1 in FIG. 14), the power operation monitoring is performed as in the operation of the second embodiment described above. The means 11 notifies the registration request transmission means 12 that the power is ON, and the registration request transmission means 12 includes a list of port numbers corresponding to the address of the terminal device 1-x and the service provided by the terminal device 1-x. Is transmitted to the relay device 2 (step D2), and the registration request receiving unit 291 of the relay device 2 receives the registration request message and processes the storage unit 27 including the port number list and address included in the registration request message. An entry of the terminal registration table is created, the entry is stored in the processing terminal registration table of the storage unit 27, and the operation check of the terminal device 1-x by the operation check request unit 293 is started. It is (step D3).
[0164]
At the same time, the power source operation monitoring unit 11 of the terminal device 1-x notifies the capability information transmission unit 16 of power ON.
[0165]
When the power information is notified, the capability information transmitting unit 16 reads the processing capability information of the terminal device 1-x stored in the storage unit 15 and includes the processing capability information and the address of the terminal device 1-x. A capability notification message is created, and the capability notification message is transmitted to the relay device 2 (step D4).
[0166]
The capability notification message transmitted to the relay apparatus 2 is received by the capability information receiving unit 294, and the capability information receiving unit 294 includes a terminal whose address field value is included in the capability notification message from the processing terminal registration table of the storage unit 27. An entry equal to the device 1-x is searched, and the processing capability information included in the capability notification message is stored in the processing capability information field of the entry.
[0167]
Thereafter, when the relay device 2 receives an IP packet from the network 5, the IP packet is received by the packet receiving unit 23, and the packet receiving unit 23 performs the same operation as in the above-described first embodiment. The IP packet is passed to the correspondence search unit 261. Similarly, the correspondence search unit 261 also sends the value of the second socket field and the value of the third socket field from the correspondence management table of the storage unit 27, respectively. An entry that is equal to the set of the address and the source port number and the set of the destination address and the destination port number is searched.
[0168]
Correspondence search means 261 performs the same processing as in the first embodiment described above, regardless of whether the entry is detected by the search or not. In particular, since the subsequent processing when the entry is detected is the same as the operation of the first embodiment described above, description thereof is omitted here.
[0169]
When the entry is not detected by the search, the registration search means 263 determines that the value of the port number field is the IP packet from the processing terminal registration table of the storage means 27, as in the operation of the first embodiment described above. In this case, when one or a plurality of entries are detected as a result of the search, all the first entry identifiers of the detected entries and the IP packet are destined as destinations. It passes to the selection means 265.
[0170]
The destination selection unit 265 reads the entry identified by the first entry identifier passed from the processing terminal registration table of the storage unit 27, and further reads the processing capability information of each terminal device from the read entry. The processing capability information is compared to select one optimal terminal device. For example, when the contents of the processing terminal registration table are as shown in FIG. 13, the destination port number of the IP packet is 10,000, and the notified first entry identifiers are 1 and 2, here the entry identifier field Since the CPU processing capability of the terminal device 1-1 having the value “1” is superior to the CPU processing capability of the terminal device 1-2 having the value “2” in the entry identifier field, the destination selection unit 265 selects the terminal device 1— 1 is selected, and the first entry identifier “1” and the IP packet are transferred to the registration unit 264.
[0171]
The processing from when the entry identifier and the IP packet are transferred to the registration unit 264 until the packet is transmitted to the terminal device 1-x is the same as the operation of the first embodiment described above. Description of is omitted.
[0172]
Further, the entry of the terminal device 1-x stored in the processing terminal registration table of the storage means 27 indicates that the terminal device 1-x is normally turned off by the relay device 2 when the power of the terminal device 1-x is turned off or for some reason. When communication becomes impossible, the deletion request receiving unit 292 or the operation confirmation requesting unit 293 deletes the same as in the operation of the second embodiment described above.
[0173]
As described above, when the relay device 2 receives an IP packet for starting data communication from the network 5, a terminal device that provides a service corresponding to a port number equal to the destination port number of the IP packet is registered in the multiple relay device 2. Even if the destination selection unit 265 selects one terminal device based on the processing capability information of the plurality of terminal devices, the terminal device that provides the service requested by the IP packet is optimized. Terminal devices can be selected.
[0174]
In addition, the processing capability information of the terminal device 1-x is stored in the storage unit 15 of the terminal device 1-x, and the capability information transmission unit 16 makes the processing capability information every time the terminal device 1-x is powered on. To the relay device 2, the capability information receiving unit 294 registers the processing capability information in the processing terminal registration table of the storage unit 27, and the terminal device 1-x is turned off, or When the normal communication with the relay device 2 cannot be performed due to the reason, the deletion request receiving unit 292 or the operation confirmation requesting unit 293 deletes the entry related to the terminal device 1-x from the processing terminal registration table, so that the terminal device When 1-x is not operating, or when the relay device 2 cannot communicate with the terminal device 1-x, an IP packet for starting data communication received from the network 5 is transmitted to the terminal device 1- It is possible to avoid having to relay on.
[0175]
In the embodiment of the present invention, the case where there is one terminal device connected to the network 5 has been described. However, the present invention can be similarly implemented even when there are a plurality of terminal devices connected to the network 5.
[0176]
In the embodiment of the present invention, a terminal device (terminal device 1-x) connected to a network different from the global network (referred to as a non-global network), and a terminal device connected to the global network (terminal device 3) In the communication system in which a plurality of non-global networks are each connected to a network having a different address system by the relay device according to the embodiment of the present invention, any communication connected to any non-global network is described. Communication between the terminal devices is also realized in the same manner. That is, in the communication system shown in FIG. 7, communication between arbitrary terminal devices is possible. This is because the terminal device (terminal device A) connected to the i-th non-global network (where i is any one of 1, 2,..., N) to the j-th non-global network (where j is When transmitting a packet for starting a communication session to a terminal device (terminal device B) connected to any one of 1, 2,..., N and j ≠ i), the i-th relay This is because the operations of the device with respect to the j-th relay device and the terminal device B are equal to those of the terminal device 3 in the embodiment of the present invention. However, when the relay network is a non-global network, the address system of the relay network must be different from both the address system of the i-th non-global network and the address system of the j-th non-global network.
[0177]
Further, in the embodiment of the present invention, the case where the terminal device 1-x is the terminal device on the other side that knows the name when the terminal device 3 starts data communication has been described. Only the name of the relay device 2 may be known, and address resolution may be performed by designating the name of the relay device 2.
[0178]
Next, a fourth embodiment of the present invention will be described with reference to FIG. 1, FIG. 15, FIG. 16, and FIG.
[0179]
In the first embodiment of the present invention, it is assumed that the port number system in the network 4 and the port number system in the network 5 are equal. On the other hand, in the present embodiment, an entry comprising a first port number field for storing the port number of the network 4 in the storage means of the relay apparatus and a second port number field for storing the port number field of the network 5 is provided. The port table manages the correspondence between the port number of the network 4 and the port number of the network 5 corresponding to the same service, and each means of the relay device uses the first port as the port number on the network 4 side. The second field is referred to as the port number on the network 5 side with reference to the number field. Thereby, even when the port number systems of the network 4 and the network 5 are different, the terminal device 1-x and the terminal device 3 can communicate.
[0180]
The configuration of the fourth embodiment of the present invention is the same as that of the first embodiment of the present invention shown in FIG. 1 except that the storage means 27 includes a port table, the address conversion means 25 and the address. The internal structure of the conversion means 26 is different.
[0181]
FIG. 17 shows the configuration of a processing terminal registration table, a correspondence management table, and a port table, which are tables provided in the storage means 27 in the present embodiment.
[0182]
As shown in FIG. 17, the configuration, usage, and usage of the processing terminal registration table and the correspondence management table are the same as those of the processing terminal registration table and the correspondence management table in the first embodiment of the present invention. However, the port number in the network 4 is stored in the port number field of the processing terminal registration table, and the port number in the network 4 is stored in the second socket field in the port number indicated in the first socket field of the correspondence management table. The port number of the network 5 is stored in the port number indicated and the port number indicated in the third socket field.
[0183]
The port table has an entry including a first port number field for storing the port number of the network 4 and a second port number field for storing the port number field of the network 5, and the port of the network 4 corresponding to the same service. The correspondence between the number and the port number of the network 5 is stored in advance. For example, assuming that the port number corresponding to the FTP service has a value of 10 in the network 4 and a value of 20 in the network 5, these correspondences are stored as shown in (3) of FIG.
[0184]
FIG. 15 shows the configuration of the address conversion means 25 in the present embodiment.
[0185]
As shown in FIG. 15, the address conversion unit 25 includes a correspondence search unit 2251, a packet conversion unit 2252, and a registration unit 2254. In the first embodiment of the present invention, the correspondence search means 251 of the address conversion means 25 is changed to the correspondence search means 2251, the packet conversion means 252 is changed to the packet conversion means 2252, and the registration means 254 is changed to the registration means 2254. It is characterized by being.
[0186]
The correspondence search unit 2251 receives the packet passed from the packet receiving unit 21 to the address converting unit 25. When the packet is received from the packet receiving unit 21, the correspondence searching unit 2251 first searches the port table of the storage unit 27 for an entry in which the value of the first port number field is equal to the value of the destination port number of the packet. .
[0187]
If the entry is not detected by the search, the correspondence search unit 2251 discards the packet and ends the process.
[0188]
When the entry is detected by the search, the correspondence search unit 2251 has a value of the first socket field equal to the set of the source address and the source port number of the packet from the correspondence management table of the storage unit 27. An entry having a value equal to the set of the destination address of the packet and the value of the second port number field of the port table entry detected in the search of the port table is searched for. .
[0189]
When the entry is detected from the correspondence management table by the search, the correspondence search unit 2251 passes the packet and the second entry identifier stored in the entry identifier field of the entry to the packet conversion unit 2252. When the entry is not detected by the search, the correspondence search unit 2251 passes the packet to the registration unit 2254.
[0190]
When the packet conversion means 2252 receives the packet and the second entry identifier, the packet conversion means 2252 converts the packet into an IP packet, and the source address and source port number of the IP packet are identified from the second entry identifier. The IP address and port number values shown in the third socket field of the corresponding management table entry are rewritten, and the destination address and destination port number of the IP packet are changed to the IP address shown in the second socket field of the entry. The address and port number are rewritten, and the rewritten IP packet is transferred to the packet transmission means 22.
[0191]
When the registration unit 2254 receives the packet, the registration unit 2254 searches the port table for an entry having the destination port number of the packet as the value of the first port number field, reads the second port number corresponding to the entry, and is unused. The second entry identifier is generated and one port number of the unused network 5 is selected. Then, the registration means 2254 uses the generated second entry identifier as the value of the entry identifier field, sets the combination of the source address and source port number of the packet as the value of the first socket field, and sets the destination of the packet. The combination of the address and the value of the second port number field of the entry of the port table detected by the search is set as the value of the second socket field, and the IP address of the network 5 of the relay device 2 and the selected port number An entry having the set as the value of the third socket field is created, and the entry is stored in the correspondence management table of the storage means 27. Further, a port table entry is created with the source port number of the packet as the value of the first port number field and the selected port number as the value of the second port number field. Register in the table. Then, the registration unit 2254 passes the packet and the second entry identifier to the packet conversion unit 2252.
[0192]
FIG. 16 shows the configuration of the address conversion means 26 in the present embodiment. As shown in FIG. 16, the address conversion unit 26 includes a correspondence search unit 261, a packet conversion unit 2262, a registration search unit 2263, and a registration unit 2264. In the first embodiment of the present invention, the packet conversion unit 262 of the address conversion unit 26 is changed to the packet conversion unit 2262, the registration search unit 263 is changed to the registration search unit 2263, and the registration unit 264 is also changed to the registration unit 2264. It is characterized by being.
[0193]
Upon receiving the IP packet and the second entry identifier, the packet conversion unit 2262 searches the port table of the storage unit 27 for an entry having the source port number of the IP packet in the second port number field, and detects it. The value of the first port number field of the entered port table entry is read. Then, the packet conversion unit 2262 converts the IP packet into a packet of the network 4, and sets the first address of the entry of the correspondence management table identified from the second entry identifier with the destination address and the destination port number of the packet. The IP address and port number of the socket are rewritten, and the transmission source port number of the packet is rewritten to the value of the first port number field of the read port table entry. To pass.
[0194]
When receiving the IP packet, the registration search means 2263 searches the port table for an entry having the destination port number of the IP packet as the value of the second port number field.
[0195]
If the entry is not detected from the port table by the search, the registration search means 2263 discards the IP packet and ends the processing.
[0196]
When the entry is detected from the port table by the search, the registration search unit 2263 further refers to the processing terminal registration table, and uses the first port number of the detected port table entry as the value of the port number field. Search for entries with field values.
[0197]
If the entry is not detected from the processing terminal registration table by the search, the registration search means 2263 discards the IP packet and ends the processing.
[0198]
When the entry is detected from the processing terminal registration table by the search, the registration search means 2263 passes the value of the first entry identifier stored in the entry identifier field of the entry and the IP packet to the registration means 2264.
[0199]
When the first entry identifier and the IP packet are passed, the registration means 2264 receives the address and port number stored in the address field of the entry in the processing terminal registration table of the storage means 27 identified by the first entry identifier. The port number stored in the field is read, an unused second entry identifier is generated, the second entry identifier is set as the value of the entry identifier field, and the set of the address and the port number is set to the first The socket field value of the IP packet, a pair of the source address and source port number of the IP packet as a second socket field, and a pair of the destination address and destination port number of the IP packet as a value of the third socket field. The entry is created and stored in the correspondence management table of the storage means 27. Further, one port number of the unused network 4 is selected, the selected port number is set as the value of the first port number field, and the source port number of the IP packet is set as the value of the second port number field. The port table entry is created, and the port table entry is registered in the port table. Then, the registration unit 2264 passes the IP packet and the second entry identifier to the packet conversion unit 2262.
[0200]
Next, the operation of the fourth exemplary embodiment of the present invention will be described.
[0201]
There are two types of data communication executed in the fourth embodiment of the present invention: a case where the terminal device 1-x starts a communication session and a case where the terminal device 3 starts. In any case, it is assumed that the correspondence between the port number of the network 4 corresponding to the service used in the communication session to be started and the port number of the network 5 is registered in the port table in advance.
[0202]
First, the operation when the terminal device 1-x starts a communication session will be described.
[0203]
Here, first, the operation when the terminal device 1-x starts a communication session for using the service in order to use the service provided by the terminal device 3 will be described. In the network 4 corresponding to the service, The port number is P4, the port number in the network 5 is P2, and the relay device 2 indicates that this is indicated by the first port number field value P4 and the second port number field value in the port table. It is assumed that an entry that is P2 is registered. Further, it is assumed that the terminal device 1-x uses the port having the port number P1.
[0204]
The terminal device 1-x sends the first packet (referred to as packet A) in order to use the service. In the packet A, the destination address is A2-1, the destination port number is P4, the source address is A1-x, and the source port number is P1.
[0205]
The packet A sent from the terminal device 1-x is received by the packet receiving means 21 of the relay apparatus 2 via the network 4, and the packet receiving means 21 passes the packet A to the address converting means 25.
[0206]
The packet A passed to the address conversion unit 25 is received by the correspondence search unit 2251.
[0207]
When the packet A is passed, the correspondence search unit 2251 first searches the port table of the storage unit 27 for an entry in which the value of the first port number field is equal to the destination port number value P4 of the packet.
[0208]
In this case, since the entry exists in the port table, the entry is detected by the search.
[0209]
Then, the correspondence search means 2251 determines from the correspondence management table of the storage means 27 that the value of the first socket field is equal to the set [A1-x, P1] of the source address and source port number of the packet A, and The value of the second socket field is equal to the set [A2-1, P2] of the destination address of the packet A and the value of the second port number field of the port table entry detected in the port table search. Search for entries with values.
[0210]
In this case, since the entry does not exist in the correspondence management table, the entry is not detected by the search.
[0211]
Therefore, the correspondence search unit 2251 passes the packet A to the registration unit 2254.
[0212]
Upon receiving the packet A, the registration unit 2254 searches the port table for an entry having the destination port number P4 of the packet A as the value of the first port number field, and generates an unused second entry identifier. Then, one port number of the unused network 5 is selected (the port number of the selected network 5 is P5). Then, the registration means 2254 uses the generated second entry identifier as the value of the entry identifier field, and sets the pair [A1-x, P1] of the source address and source port number of the packet A to the first socket field. And the pair [A2-1, P2] of the second port number field of the port table entry detected by the search and the destination address of the packet A is set as the value of the second socket field, and the relay An entry having the set [A2-2, P5] of the IP address of the network 2 of the apparatus 2 and the selected port number as the value of the third socket field is created, and the entry is stored in the correspondence management table of the storage means 27. Remember. Furthermore, a port table entry is created with the source port number P1 of the packet A as the value of the first port number field and the selected port number P5 as the value of the second port number field, Register the entry in the port table. Then, the registration unit 2254 passes the packet A and the second entry identifier to the packet conversion unit 2252.
[0213]
The packet converting means 2252 receives the packet A and the second entry identifier, converts the packet A into an IP packet, and sets the source address and source port number of the IP packet to the second entry, respectively. The IP address A2-2 and port number P5 indicated in the third socket field of the entry of the correspondence management table identified from the identifier are rewritten, and the destination address and destination port number of the IP packet are changed to the first address of the entry. 2 is rewritten to the IP address A2-1 and the port number P2 shown in the socket field 2 and the rewritten IP packet (referred to as IP packet B) is passed to the packet transmitting means 22. At this time, in the IP packet B, the destination address is A2-1, the destination port number is P2, the source address is A2-2, and the source port number is P5.
[0214]
The IP packet B passed to the packet transmission unit 22 is transmitted to the terminal device 3 via the network 5. Since the destination address of the IP packet B is A2-1, the destination port number is P2, the transmission source address is A2-2, and the transmission source port number is P5, in the terminal device 3, the communication session is address A2-2. The IP packet transmitted from the terminal device 3 relating to the communication session is interpreted as a communication session between the port P5 of the terminal device and the port P2 of the own terminal device, and the destination address is A2-2 and the destination port number is P5. The source address is A2-1 and the source port number is P2.
[0215]
Thereafter, when the relay device 2 receives the packet (referred to as packet C) of the communication session from the network 4, it operates in the same manner as the processing of the packet A described above, but the correspondence management table retrieval processing of the correspondence retrieval means 2251. In this case, the correspondence search means 2252 then reads from the correspondence management table of the storage means 27 that the value of the first socket field is a set [A1-x, P1] of the source address and source port number of the packet C. A pair [A2-1, P2] in which the second socket field value is equal and the destination address of the packet C and the second port number field value of the port table entry detected in the port table search are Find equal entries. Then, the correspondence search unit 2251 passes the packet C and the second entry identifier stored in the entry identifier field of the entry directly to the packet conversion unit 2252 without going through the registration unit 2254. The subsequent processing is performed in the same manner as in the case of the packet A, and the packet C has the same source address A2-2, source port number P5, destination address A2-1, destination port number P2 as the IP packet B. (The converted IP packet is called an IP packet D), and is sent to the terminal device 3 via the network 5 as the converted IP packet D.
[0216]
Further, as described above, the IP packet (referred to as IP packet E) of the communication session transmitted from the terminal device 3 after processing the packet A and the IP packet B has a destination address of A2-2 and a destination port number. Is P5, the source address is A2-1, and the source port number is P2, and is received by the packet receiving unit 23 of the relay apparatus 2 via the network 5, and the packet receiving unit 23 converts the IP packet E into the address converting unit. 26.
[0217]
The IP packet E passed to the address translation unit 26 is received by the correspondence search unit 261. Correspondence search means 261 determines from the correspondence management table of storage means 27 that the value of the second socket field is equal to the pair [A2-1, P2] of the source address and source port number of IP packet E, and An entry in which the value of the third socket field is equal to the set [A2-2, P5] of the destination address and destination port number of the IP packet is searched.
[0218]
In this case, since the entry registered at the time of packet A processing exists in the correspondence management table, and the entry corresponds to the entry to be searched, the correspondence search means 261 uses the IP packet E and the entry identifier of the entry as a packet. It passes to the conversion means 2262.
[0219]
Upon receiving the IP packet E and the second entry identifier, the packet conversion unit 2262 searches the port table of the storage unit 27 for an entry having the source port number P2 of the IP packet in the second port number field. Then, the value P4 of the first port number field of the detected port table entry is read. Then, the packet converting means 2262 converts the IP packet E into a packet of the network 4, and the first address of the entry of the correspondence management table identified from the second entry identifier by the destination address and the destination port number of the packet. Is rewritten to the IP address A1-x and the port number value P1, and the transmission source port number of the packet is rewritten to the read P4, and the rewritten packet (referred to as packet F) is sent to the packet transmission means 24. hand over.
[0220]
When the packet transmission means 24 is passed the packet F, the packet transmission means 24 sends the packet F to the network 4 and the packet F is received by the terminal device 1-x.
[0221]
Next, an operation when the terminal device 3 starts a communication session will be described.
[0222]
Here, the operation when the terminal device 3 starts a communication session for using the service in order to use the service provided by the terminal device 1-x will be described. In the network 4 corresponding to the service, The port number is P1, the port number in the network 5 is P5, and in order to indicate this correspondence to the relay device 2, the value of the first port number field is P1 and the value of the second port number field is in the port table. It is assumed that the entry P5 is registered and the correspondence between the address A1-x and the port number P1 is stored in the processing terminal registration table. Further, it is assumed that the terminal device 3 uses the port having the port number P2.
[0223]
Before the terminal device 3 transmits the first IP packet (referred to as IP packet A) to use the above service, first, the terminal device 1-x first operates in the same manner as the operation of the first embodiment of the present invention. Address resolution is performed from the name, and it is known that the destination IP address of the IP packet addressed to the terminal device 1-x is A2-2, but the description is omitted here.
[0224]
Next, the terminal device 3 sends out the IP packet A. The IP packet A has a destination address A2-2, a destination port number P5, a source address A2-1, and a source port number P2.
[0225]
The IP packet A is received by the packet receiving unit 23 of the relay apparatus 2 via the network 5, and the packet receiving unit 23 passes the IP packet A to the address converting unit 26.
[0226]
The IP packet A passed to the address translation unit 26 is received by the correspondence search unit 261. When the correspondence search means 261 receives the IP packet A, the correspondence management table of the storage means 27 indicates that the values of the second socket field and the third socket field are the sender address and sender of the IP packet A, respectively. An entry having a value equal to the set [A2-1, P2] of the port number and the set [A2-2, P5] of the destination address and destination port number of the IP packet A is searched.
[0227]
In this case, since the entry does not exist in the correspondence management table, the entry is not detected by the search.
[0228]
The correspondence search unit 261 passes the IP packet A to the registration search unit 2263 because the entry has not been detected in the search.
[0229]
Upon receiving the IP packet A, the registration search means 2263 searches the port table for an entry having the destination port number P5 of the IP packet A as the value of the second port number field.
[0230]
In this case, as described above, an entry in which the value of the first port number field is P1 and the value of the second port number field is P5 is registered in the port table, and the entry is detected.
[0231]
Since the entry is detected from the port table by the search, the registration search means 2263 further refers to the processing terminal registration table, and uses the first port number of the detected port table entry as the value of the port number field. The entry having the field value P1 is searched.
[0232]
Also in this case, as described above, the correspondence between the address A1-x and the port number P1 is stored in the processing terminal registration table, and the entry is detected.
[0233]
Since the entry is detected from the processing terminal registration table by the search, the registration search means 2263 sends the value of the first entry identifier stored in the entry identifier field of the entry and the IP packet A to the registration means 2264. hand over.
[0234]
When the registration means 2264 is passed the first entry identifier and the IP packet A, the address stored in the address field of the entry in the processing terminal registration table of the storage means 27 identified by the first entry identifier. A1-x and the port number P1 stored in the port number field are read out, an unused second entry identifier is generated, the second entry identifier is set as the value of the entry identifier field, and the address and the address A set of port numbers [A1-x, P1] is set as the value of the first socket field, and a set of the source address and source port number of the IP packet A [A2-1, P2] is set in the second socket field. And a pair [A2-2, P5] of the destination address and destination port number of the IP packet is set as the value of the third socket field. Create an entry, and registers the entry in the corresponding management table of the storage unit 27. Furthermore, one port number of the unused network 4 is selected (the selected port number is P4), the selected port number P4 is set as the value of the first port number field, and the IP packet A A port table entry is created with the source port number P2 as the value of the second port number field, and the port table entry is registered in the port table. Then, the registration unit 2264 passes the IP packet A and the second entry identifier to the packet conversion unit 2262.
[0235]
When the packet converting unit 2262 receives the IP packet A and the second entry identifier, the packet converting unit 2262 has an entry having the source port number P2 of the IP packet A in the second port number field from the port table of the storage unit 27. And the value P4 of the first port number field of the detected port table entry is read. Then, the packet conversion unit 2262 converts the IP packet A into a packet of the network 4, and sets the first address of the entry of the correspondence management table identified from the second entry identifier with the destination address and the destination port number of the packet. The socket IP address A1-x and the port number P1 are rewritten, the transmission source port number of the packet is rewritten to the read P4, and the rewritten packet (referred to as packet B) is sent to the packet transmission means 24. hand over.
[0236]
When the packet B is delivered, the packet transmission means 24 sends the packet B to the network 4 and the packet B is received by the terminal device 1-x. Since the destination address of the packet B is A1-x, the destination port number is P1, the transmission source address is A2-1, and the transmission source port number is P4, in the terminal device 1-x, the communication session is address A2- A packet transmitted from the terminal device 1-x relating to the communication session is interpreted as a communication session between the port P4 of the terminal device 1 and the port P1 of the own terminal device, and the destination address is A2-1. Is P4, the source address is A1-x, and the source port number is P1.
[0237]
Thereafter, when receiving the IP packet (referred to as IP packet C) of the communication session from the network 5, the relay device 2 operates in the same manner as the processing of the IP packet A described above, but searches the correspondence management table of the correspondence search means 261. In this processing, the correspondence search unit 261 now determines that the values of the second socket field and the third socket field are the source address and source port number of the IP packet C from the correspondence management table of the storage unit 27, respectively. Entry [A2-1, P2] and an entry having a value equal to the destination address and destination port number set [A2-2, P5] of the IP packet C are detected. Then, the correspondence detection unit 261 directly transmits the IP packet C and the second entry identifier stored in the entry identifier field of the entry without using the registration search unit 2263 and the registration unit 2264. 2262. Subsequent processing is performed in the same manner as in the case of the IP packet A, and the IP packet C has the same source address A2-2, source port number P4, destination address A1-x, destination port as the packet B. The packet is converted into a packet having the number P1 (the converted packet is called a packet D), and the converted packet D is sent to the terminal device 1-x via the network 4.
[0238]
Further, as described above, the packet (referred to as packet E) of the communication session sent from the terminal device 1-x after processing the IP packet A and packet B has the destination address A2-1 and the destination port number. Is P4, the source address is A1-x, and the source port number is P1, and is received by the packet receiving unit 21 of the relay apparatus 2 via the network 4, and the packet receiving unit 21 converts the packet E into the address converting unit 25. To pass.
[0239]
The packet E passed to the address translation means 25 is received by the correspondence search means 2251. When the packet E is passed, the correspondence search means 2251 first searches the port table of the storage means 27 for an entry whose value of the first port number field is equal to the destination port number value P4 of the packet E.
[0240]
In this case, in the port table, there is an entry registered at the time of the IP packet A processing, and the entry corresponds to the entry to be searched. Therefore, the correspondence search means 2251 further reads from the correspondence management table of the storage means 27. The value of the first socket field is equal to the source address and source port number pair [A1-x, P1] of the packet E, and the value of the second socket field is the destination address of the packet E. An entry having a value equal to the value set [A2-1, P2] in the second port number field of the port table entry detected in the port table search is searched.
[0241]
In this case, since the entry registered at the time of processing the IP packet A exists in the correspondence management table and the entry corresponds to the entry to be searched, the correspondence search means 2251 stores the packet E and the entry identifier field of the entry. The stored second entry identifier is transferred to the packet converting means 2252.
[0242]
When the packet conversion unit 2252 receives the packet E and the second entry identifier, the packet conversion unit 2252 converts the packet E into an IP packet, and sets the source address and the source port number of the IP packet to the second entry. The IP address A2-2 and port number P5 indicated in the third socket field of the entry of the correspondence management table identified from the identifier are rewritten, and the destination address and destination port number of the IP packet are changed to the first address of the entry. 2 is rewritten to the IP address A2-1 and the port number P2 shown in the socket field 2, and the rewritten IP packet (referred to as IP packet F) is passed to the packet transmitting means 22.
[0243]
When receiving the IP packet F, the packet transmission means 22 sends the IP packet F to the network 5, and the IP packet is received by the terminal device 3.
[0244]
In the embodiment of the present invention, the case where there is one terminal device connected to the network 5 has been described. However, the present invention can be similarly implemented even when there are a plurality of terminal devices connected to the network 5.
[0245]
In the embodiment of the present invention, a terminal device (terminal device 1-x) connected to a network different from the global network (referred to as a non-global network), and a terminal device connected to the global network (terminal device 3) In the communication system in which a plurality of non-global networks are each connected to a network having a different address system by the relay device according to the embodiment of the present invention, any communication connected to any non-global network is described. Communication between the terminal devices is also realized in the same manner. That is, in the communication system shown in FIG. 7, communication between arbitrary terminal devices is possible. This is because the terminal device (terminal device A) connected to the i-th non-global network (where i is any one of 1, 2,..., N) to the j-th non-global network (where j is When transmitting a packet for starting a communication session to a terminal device (terminal device B) connected to any one of 1, 2,..., N and j ≠ i), the i-th relay This is because the operations of the device with respect to the j-th relay device and the terminal device B are equal to those of the terminal device 3 in the embodiment of the present invention. However, when the relay network is a non-global network, the address system of the relay network must be different from both the address system of the i-th non-global network and the address system of the j-th non-global network.
[0246]
Further, in the embodiment of the present invention, the case where the terminal device 1-x is the terminal device on the other side that knows the name when the terminal device 3 starts data communication has been described. Only the name of the relay device 2 may be known, and address resolution may be performed by designating the name of the relay device 2.
[0247]
Further, in the fourth embodiment of the present invention, the first embodiment of the present invention is different from the configuration of FIG. 1 in that the storage means 27 includes a port table, and the address conversion means 25 and the address conversion means 26. 8 and 11 are the second and third embodiments, the storage means 27 is provided with a port table, and the address conversion means 25 and the address are similarly provided. By making the internal structure of the conversion unit 26 different, the correspondence search unit 251 of the address conversion unit 25 and the registration search unit 263 of the address conversion unit 26 search the processing terminal registration table after searching the port table. Can be applied.
[0248]
Next, an embodiment of a medium that records the communication program of the present invention will be described. In the present embodiment, the terminal device 1-x and the relay device 2 according to the first, second, third, and fourth embodiments of the present invention each include a data processing device and a storage device, and further a communication program. (Not shown in particular). This recording medium may be a magnetic disk, semiconductor memory, CD-ROM or other recording medium.
[0249]
The communication program for controlling the relay device 2 is read from the recording medium into the storage device of the relay device 2, and the processing terminal registration table and the correspondence management table are stored in the storage unit 27. In the medium embodiment corresponding to the third embodiment, a processing terminal registration table including capability information is further stored, and in the medium embodiment corresponding to the fourth embodiment, further, A port table is stored.
[0250]
Then, the data processing device generates packet receiving means 21 and 23, packet transmitting means 22 and 24, address conversion means 25 and 26, and address inquiry response means 28, and controls their operations. In the medium embodiment corresponding to the second embodiment, a registration request receiving unit 291, an operation confirmation requesting unit 293, and a deletion request receiving unit 292 are further generated to correspond to the third embodiment. In the embodiment of the medium, the capability information receiving means 294 is further generated and its operation is controlled.
[0251]
The data processing device executes the same processing as the communication processing described in the relay device 2 in the first, second, third, and fourth embodiments under the control of the communication program described above.
[0252]
In the embodiment of the medium corresponding to the second embodiment, the communication program for controlling the terminal device 1-x is read from the recording medium into the terminal device 1-x, and the power operation monitoring means 11, A registration request transmission unit 12, an operation confirmation response unit 14, and a deletion request transmission unit 13 are generated and their operations are controlled. In the medium embodiment corresponding to the third embodiment, the capability information transmitting means 16 is further generated and its operation is controlled. In the medium embodiment corresponding to the second embodiment, the provided service list is stored in the storage unit 15. In the embodiment of the medium corresponding to the third embodiment, the processing capability information is further stored in the storage unit 15.
[0253]
The data processing device executes the same processing as the communication processing by the terminal device 1-x in the second and third embodiments under the control of this communication program.
[0254]
【Example】
Next, a first embodiment of the present invention will be described with reference to the drawings. This example corresponds to the first embodiment of the present invention.
[0255]
As shown in FIG. 18, the present embodiment employs a private address system (192.168..xxx.xxx) configured by an Ethernet (R) network as the network 4 and managed by the owner of the Ethernet (R) network. A terminal device used by an external user as an IP network, an existing Internet adopting a global address system as a network 5, a personal computer as a terminal device 1-x, an ISDN router as a relay device 2, and a terminal device 3 It has. The ISDN router is connected to an ISP (Internet Service Provider) network by an ISDN network.
[0256]
A network system composed of the network 4 and devices connected to the network 4 is directly connected to the Ethernet (R) cable and the Ethernet (R) cable wired in the individual's home or the Ethernet (R) hub. It can be a personal in-home network system composed of personal computers connected via the network, or a small office home office (SOHO) of a small-scale office constructed with a similar configuration. Here, an FTP server program that provides FTP (File Transfer Protocol) service is installed in the Ethernet (R), and the name is ftp. user-a. isp1. ne. a terminal device whose address is 192.168.0.2 and a program for sending and receiving e-mail are installed, and the name is pc1. user-1. isp1. ne. It is assumed that a terminal device that is jp is connected.
[0257]
The ISDN router is named user-a. isp1. ne. It is assumed that 192.168.0.1 is assigned as the Ethernet (R) side address and 133.1.1.5 is assigned as the global address assigned by the ISP.
[0258]
Here, it is assumed that the FTP server provides the FTP service to the external user terminal device. In this case, the address of the FTP server and the port number 20 corresponding to the FTP service are registered in advance in the processing terminal registration table of the ISDN router ((1) in FIG. 19). It is assumed that there is no entry in the correspondence management table.
[0259]
At this time, the external user terminal is connected to the user-a. isp1. ne. It is assumed that data communication for using the FTP service is started for jp.
[0260]
The external user terminal device is user-a. isp1. ne. When an address resolution inquiry message is created from the name of jp and the address resolution inquiry message is transmitted (step A1 in FIG. 6), an ISDN router device or a network server that can resolve the address of the ISDN router device in the ISP An address resolution response message is generated in response to the address resolution inquiry message, and the address resolution response message is transmitted to the external user terminal device (step A2). At this time, the address resolution response message includes information that the address of the ISDN router inquired by the address resolution inquiry message is 133.1.1.5.
[0261]
When the external user terminal device receives the address resolution response message, the destination address is the address 133.1.1.5 notified by the address resolution response message, and the destination port number is 20 corresponding to the FTP service. Yes, an IP packet whose source address is 208.192.0.1 which is the address of the external user terminal device and whose source port number is 1024 is created, and the IP packet is transmitted to the ISDN router.
[0262]
In the ISDN router, when the IP packet is received, the IP packet is transferred from the packet receiving means 23 to the correspondence search means 261. Since there is no entry corresponding to the IP packet in the correspondence management table, the IP packet is registered. Passed to the search means 263.
[0263]
The registration retrieval unit 263 refers to the processing terminal registration table. Here, since the entry having a value of 20 in which the port number field is equal to the destination port number of the IP packet exists in the processing terminal registration table, the registration unit 264 Is passed the entry identifier 1 of the entry and the IP packet.
[0264]
The registration unit 264 registers the correspondence regarding the IP packet in the correspondence management table from the contents of the entry in the processing terminal registration table corresponding to the passed entry identifier and the contents of the passed IP packet ((2 in FIG. 19). )).
[0265]
Thereafter, the ISDN router refers to the registered correspondence management table entry and relays the IP packet between the port number 20 of the FTP server and the port number 1024 of the external user terminal device.
[0266]
In the first embodiment, an example in which the network 4 is configured by Ethernet (R) has been shown. However, the network 4 may be a network using another communication medium or communication protocol such as IEEE 1394 or wireless LAN.
[0267]
The connection from the relay device 2 to the network 5 may be a dedicated line, and the relay device 2 may be an IP router provided with an interface device that accommodates the dedicated line.
[0268]
Next, a second embodiment of the present invention will be described with reference to the drawings. Such an example corresponds to the fourth embodiment of the present invention.
[0269]
As shown in FIG. 20, in this embodiment, a wireless network using the Bluetooth technology described in “Bluetooth Specification version 1.0 A” is used as the network 4, and an IP network including the existing Internet and a mobile communication network as the network 5. A portable information device having a communication function as a slave in the Bluetooth technology as the terminal device 1-x, a TCP / IP communication function with the IP network as a relay device 2, and a communication function as a master in the Bluetooth technology A mobile phone terminal device having a protocol conversion function between these protocols and having a function of relaying communication between the network 4 and the network 5 is provided as a terminal device 3 used by an external user. .
[0270]
Here, as a portable information device used as the terminal device 1-x, a camera, a video camera, and a notebook PC are taken as examples, and it is assumed that addresses 1, 2, and 3 in Bluetooth are assigned. The notebook PC is an FTP server dedicated device that is equipped with an FTP server program that interprets the FTP protocol and provides an FTP service and a storage device that stores files, and performs direct communication with a mobile phone terminal using Bluetooth technology. And
[0271]
The mobile phone terminal has a name user-a. op1. co. It is assumed that jp is assigned and the global address 133.1.1.5 of the network 5 is assigned.
[0272]
The port number of the network 4 corresponding to the FTP service is 10 and the port number of the network 5 is 20.
[0273]
Here, it is assumed that the notebook PC provides an FTP service to the external user terminal device. In this case, the port table of the cellular phone device shows the correspondence between the port number 10 of the network 4 corresponding to the FTP service and the port number 20 of the network 5 ((3) in FIG. 21), and the processing terminal registration table shows The correspondence between the address 3 of the notebook PC and the port number 10 of the network 4 corresponding to the FTP service ((1) in FIG. 21) is registered in advance. It is assumed that there is no entry in the correspondence management table.
[0274]
At this time, the external user terminal is connected to the user-a. op1. co. It is assumed that data communication for using the FTP service is started for jp.
[0275]
The external user terminal device is user-a. op1. co. When an address resolution inquiry message is created from the name of jp and the address resolution inquiry message is transmitted (step A1 in FIG. 6), the mobile phone terminal or a network that can resolve the address of the mobile terminal device in the mobile communication network The server creates an address resolution response message in response to the address resolution inquiry message, and transmits the address resolution response message to the external user terminal device (step A2). At this time, the address resolution response message includes information that the address of the mobile phone terminal inquired by the address resolution inquiry message is 133.1.1.5.
[0276]
When the external user terminal device receives the address resolution response message, the destination address is the address 133.1.1.5 notified by the address resolution response message, and the destination port number is 20 corresponding to the FTP service. Yes, an IP packet whose source address is 208.192.0.1 which is the address of the external user terminal device and whose source port number is 1024 is created, and the IP packet is transmitted to the mobile phone terminal.
[0277]
When the mobile phone terminal receives the IP packet, the IP packet is passed from the packet receiving means 23 to the correspondence search means 261. Since there is no entry corresponding to the IP packet in the correspondence management table, the IP packet is Passed to the registration search means 2263.
[0278]
The registration search means 2263 knows that the port number of the network 4 corresponding to the destination port number 20 of the IP packet is 10 by searching the port table, and further searches for the port number 10 by searching the processing terminal registration table. Since an entry in which the address of the terminal device of the network 4 providing the service is registered is detected, the registration search unit 2263 passes the IP packet and the entry identifier 1 of the entry to the registration unit 2264.
[0279]
The registration unit 2264 registers the correspondence regarding the IP packet in the correspondence management table from the contents of the entry in the processing terminal registration table corresponding to the passed entry identifier 1 and the contents of the passed IP packet (( 2)).
[0280]
Thereafter, the mobile phone terminal refers to the entry of the registered correspondence management table, and performs communication using Bluetooth with the FTP server program of the notebook PC and communication using TCP / IP between the port number 1024 of the external user terminal device. Relay.
[0281]
【The invention's effect】
The first effect is that data communication can be started from a terminal device connected to the global network to a terminal device connected to the private network.
[0282]
The reason is that the relay device connecting the global network and the private network manages the correspondence between the address of the terminal device connected to the private network and the port number corresponding to the service provided by the terminal device, and refers to the correspondence. Since the destination of the packet for starting data communication from the terminal device connected to the global network is converted and relayed, the relay device supports one global address for a plurality of terminal devices connected to the private network. This is because the terminal device to which the IP packet is transferred can be identified by the value of the destination port number included in the IP packet for starting data communication even in such a case.
[0283]
The second effect is that the address of the partner terminal device can be resolved between the terminal devices connected to different private networks. This enables data communication between terminal devices connected to different private networks.
[0284]
The reason is the same as the reason for the first effect.
[0285]
A third effect is that an IP packet that starts data communication is relayed only when a terminal device connected to the private network is operating. As a result, it is possible to prevent useless relaying of IP packets for which no terminal device is present.
[0286]
The reason is that the terminal device connected to the private network registers the service to be provided to the relay device when activated, and deletes the registered service when terminated.
[0287]
The fourth effect is that when a terminal device connected to the private network cannot operate normally due to some abnormality, an IP packet for starting data communication is not relayed. As a result, it is possible to prevent the receiving terminal device from wastefully relaying an IP packet that is not operating normally.
[0288]
The reason is that it is confirmed whether or not the relay device is periodically operating normally with respect to the terminal device connected to the private network in which the service is registered.
[0289]
The fifth effect is that, as shown in the first and second embodiments, it is possible to provide the same service by being connected to the private network in a situation where one user manages the private network. In the case where there are a plurality of terminal devices, even if the terminal device that currently provides the service ends the operation, the terminal that can automatically provide the other service in response to a request for the service thereafter It is possible to communicate with the device.
[0290]
The reason is that, in the private network, the port number resource is shared between the terminal devices connected to the private network, and the terminal device is as described above for the reasons of the third effect and the fourth effect. Since the registration of the service provided by the terminal device is automatically deleted when the terminal device becomes inoperative, even if the terminal device that currently provides the service terminates the operation, This is because it is possible to relay to the other terminal device that has registered the provision of the service in response to the request.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of a first exemplary embodiment of the present invention.
FIG. 2 is a block diagram showing a partial configuration of the first exemplary embodiment of the present invention.
FIG. 3 is a block diagram showing a partial configuration of the first exemplary embodiment of the present invention.
FIG. 4 is a diagram showing a configuration of a table according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a message configuration in the first embodiment of the present invention;
FIG. 6 is a sequence diagram showing the operation of the first exemplary embodiment of the present invention.
FIG. 7 is a block diagram showing another configuration according to the embodiment of the present invention.
FIG. 8 is a block diagram showing the configuration of the second exemplary embodiment of the present invention.
FIG. 9 is a first sequence diagram showing the operation of the second exemplary embodiment of the present invention.
FIG. 10 is a second sequence diagram showing the operation of the second exemplary embodiment of the present invention.
FIG. 11 is a block diagram showing the configuration of the third exemplary embodiment of the present invention.
FIG. 12 is a block diagram showing a partial configuration of the third embodiment of the present invention;
FIG. 13 is a diagram showing a configuration of a part of a table according to the third embodiment of the present invention.
FIG. 14 is a sequence diagram showing the operation of the third exemplary embodiment of the present invention.
FIG. 15 is a block diagram showing a partial configuration of the fourth exemplary embodiment of the present invention.
FIG. 16 is a block diagram showing a partial configuration of the fourth exemplary embodiment of the present invention;
FIG. 17 is a block diagram showing a configuration of a table in the fourth embodiment of the present invention;
FIG. 18 is a block diagram showing the configuration of the first exemplary embodiment of the present invention.
FIG. 19 shows the contents of a table in the first embodiment of the present invention.
FIG. 20 is a block diagram showing a configuration of a second exemplary embodiment of the present invention.
FIG. 21 is a diagram showing the contents of a table in the second embodiment of the present invention.
FIG. 22 is a block diagram showing the configuration of an existing technology.
FIG. 23 is a block diagram showing a configuration of a part of an existing technology.
FIG. 24 is a block diagram showing the configuration of part of the existing technology.
FIG. 25 is a block diagram showing an example of an existing IP network configuration
[Explanation of symbols]
1 Mobile device
2 Relay device
3 Terminal equipment
4 network
5 network
6 Power supply operation monitoring means
12 Registration request sending means
13 Delete request transmission means
14 Operation confirmation response means
15 Memory means
21 Packet receiving means
22 Packet transmission means
23 Packet receiving means
24 packet transmission means
25 Address conversion means
26 Address conversion means
27 Memory means
28 Address inquiry response means
251 Corresponding search means
252 Packet conversion means
254 registration means
261 Corresponding search means
262 packet conversion means
263 Registration search means
H.264 registration means
265 destination selection means
291 Registration request receiving means
292 Delete request receiving means
293 operation confirmation request means
294 capability information receiving means
1021 Packet receiving means
1022 Packet transmission means
1023 Packet receiving means
1024 packet transmission means
1025 Address conversion means
1026 Address conversion means
1027 Storage means
1251 Corresponding search means
1252 Packet conversion means
1254 Registration means
1261 Corresponding search means
1262 Packet conversion means
2251 correspondence search means
2252 packet conversion means
2254 registration means
2262 packet conversion means
2263 Registration search means
2264 registration means

Claims (16)

A first network and a second network having a different address system from the first network are connected via a relay device;
The first terminal device connected to the first network is:
Notifying the relay device of a registration request including the address of the first terminal device and a service identifier of the service provided by the first terminal device;
The relay device receives the registration request, and includes an address of a first terminal device connected to the first network included in the registration request, a service identifier of a service provided by the first terminal device, and One or a plurality of first entries including the above are stored in the first management table,
A second terminal device connected to the second network transmits a packet addressed to a service;
When the relay apparatus receives the packet, the relay apparatus searches the first management table for a first entry having the same service identifier as the destination service identifier included in the packet, and detects the destination address of the packet. A communication method comprising: rewriting an address of a first terminal device in one entry and transmitting the packet to the first terminal device. The first terminal device connected to the first network notifies the relay device of a deletion request including the address of the terminal device,
The relay device is
When the deletion request is received, the first entry having the address of the terminal device included in the deletion request is searched from the first management table, and the first entry detected by the search is deleted. The communication method according to claim 1 . 3. The processing capability information of the first terminal device connected to the first network is included in one or more first entries of the first management table. The communication method described. The first terminal device connected to the first network notifies the relay device of a capability notification message including the address of the terminal device and processing capability information,
When the relay device receives the capability notification message, the relay device stores processing capability information included in the capability notification message in a first entry of the first terminal device of the first management table. The communication method according to claim 1, 2 or 3. The relay apparatus determines a first entry based on the processing capability information when a plurality of first entries having the same service identifier as a destination service identifier included in the packet are detected. Item 5. A communication method according to Item 3 or 4. A relay device for connecting a first network and a second network having a different address system from the first network,
When receiving a registration request including the address of the first terminal device and the service identifier from the first terminal device connected to the first network, the address and service identifier of the first terminal device included in the registration request Means for storing in the first management table a first entry including:
First management for storing one or more first entries including an address of a first terminal device connected to the first network and a service identifier of a service provided by the first terminal device With a table
A first entry having the same service identifier as the destination service identifier included in the packet from the first management table for a packet addressed to a service from the second terminal device connected to the second network A first search means for searching for;
Means for rewriting the destination address of the packet with the address of the first terminal device of the first entry detected by the first search means. When a deletion request including the address of the first terminal device is received from the first terminal device, the first entry having the address of the first terminal device included in the deletion request is searched and detected. 7. The relay apparatus according to claim 6, further comprising means for deleting the first entry from the first management table. Operation of the first terminal device by transmitting an operation confirmation request message to the first terminal device connected to the first network and receiving an operation confirmation response message from the first terminal device. If the operation of the first terminal device cannot be confirmed, the first entry having the address of the first terminal device that has transmitted the operation confirmation request message is retrieved from the first management table. 8. The relay apparatus according to claim 6, further comprising an operation confirmation requesting unit for deleting the detected first entry. The relay apparatus according to claim 7 or 8, wherein the first entry of the first management table includes processing capability information of the first terminal device connected to the first network. . When a capability notification message including the address of the terminal device and processing capability information is received from the first terminal device connected to the first network, the first terminal device of the first management table 10. The relay apparatus according to claim 7, 8 or 9, wherein the first entry includes means for storing processing capacity information included in the capacity notification message. When a plurality of first entries having the same service identifier as the destination service identifier included in the packet are detected, the first entry is determined based on the processing capability information. The relay device according to claim 9 or 10. When receiving a registration request including an address of the first terminal device and a service identifier from the first terminal device connected to the first network, the first management table includes the first request included in the registration request. Means for storing a first entry including a terminal device address and a service identifier;
A recording medium that records a communication program of a relay device that connects a first network and a second network having a different address system from the first network,
First management for storing one or more first entries including an address of a first terminal device connected to the first network and a service identifier of a service provided by the first terminal device Table,
A first entry having the same service identifier as the destination service identifier included in the packet from the first management table for a packet addressed to a service from the second terminal device connected to the second network A first search means for searching for;
A communication program is recorded that causes the relay device to function as a conversion means for rewriting the destination address of the packet with the address of the first terminal device of the first entry detected by the first search means. recoding media. When receiving a deletion request including the address of the first terminal device from the first terminal device, a first entry having an address of the first terminal device included in the deletion request from the first management table 13. The recording medium having the communication program recorded thereon according to claim 12, wherein the relay device functions as a means for searching for and deleting the detected first entry. The communication program according to claim 12 or 13, wherein the first entry of the first management table includes processing capability information of the first terminal device connected to the first network. A recording medium on which is recorded. When a capability notification message including the address of the terminal device and processing capability information is received from the first terminal device connected to the first network, the first terminal device of the first management table 15. The recording medium having a communication program recorded thereon according to claim 12, 13, or 14, wherein said relay device functions to store processing capability information included in said capability notification message in a first entry. When the plurality of first entries having the same service identifier as the destination service identifier included in the packet are detected, the relay device is caused to function as a means for determining the first entry based on the processing capability information. A recording medium on which the communication program according to claim 14 is recorded.

Images