JP3928662B2 - Address translation apparatus, message processing method and apparatus - Google Patents

Description

The present invention relates to a system for interconnecting networks according to the same protocol or networks according to different protocols.

The Internet (IP) network such as the Internet is rapidly developing. With the rapid increase in Internet users, the rate of data communication in the communication network is increasing. Telecom operators are building next-generation IP-based communication networks and are considering the fusion of data and voice communications.
VoIP (Voice over IP) is a technology for transmitting voice information over an IP network. In VoIP, a virtual communication path (session) is first set between communication devices. IP packetized voice data is transferred on the set communication path. A session control protocol is required to control session establishment, maintenance, and disconnection between communication devices.
The Internet Engineering Task Force (IETF) establishes and terminates sessions for IP multimedia communications, using SIP (Session Initiation Protocol) (IETF RFC
2543) was specified. SIP is attracting attention as a VoIP session control protocol because of its high functionality extensibility.
SIP is an application protocol that uses transport mechanisms such as TCP (Transmission Control Protocol) and UDP (User Datagram Protocol).
SIP is a text-based protocol and consists of a header part that carries a request or response and a message body that describes the contents of the session. For example, SDP (Session Description Protocol) (IETF RFC2327) is applied to the SIP session description.
SIP employs a client-server model architecture. The outgoing client sends a SIP request to the incoming client's proxy (SIP server). SI
The P server establishes a session between terminals by resolving the address of the communication destination using DNS (Domain Name System) or the like.
The SIP server has a Proxy mode and a Redirect mode depending on its role. Proxy mode is used to proxy a session establishment request between an outgoing client and an incoming client.
It is the method that Server mediates. In Redirect mode, the outgoing client is SIP Redi
This is a method of directly connecting to an incoming client by using information on the destination received from the rect server.
Hereinafter, a SIP connection procedure using a SIP server in Proxy mode will be described. IP network terminal x
When starting voice communication using SIP with terminal y in the IP network, terminal x transmits a call setting request (INVITE) to the SIP server. The SIP server specifies the location information of the terminal y and transmits a call setting request. The terminal y transmits a response indicating acceptance of the call. This response is transmitted to the terminal x via the SIP server through which the call setting request has passed. Terminal x confirms receipt of the response by sending an ACK request to terminal y. The ACK request is transferred by the SIP server or directly transmitted to the terminal y. Terminal x
And terminal y can be communicated. Normally, call setup requests and responses are sent to terminal x and terminal y.
Includes information (session description) for transferring user information (voice packets) between the two. SDP or the like is applied to the session description. Terminal x (terminal y) is terminal y
User information is sent to a destination designated by (terminal x).
According to the specifications of SIP and SDP, information on terminals and SIP servers can be specified by IP addresses.
On the other hand, with the rapid spread of IP networks, technology for interconnecting areas with different address systems has become important.
For example, as a technology for interconnecting networks that follow private addresses and networks that follow public addresses, a method using NAT (Network Address Translator) technology (IETF RF
C1631) is known.
NAT performs conversion between a private IPv4 address and a public IPv4 address. Basic
NAT is when a datagram passes between two areas connected by a NAT router.
Rewrite either the source address or the destination address. When the address space of the private network and the address space of the public network collide, twice NAT technology is often used to resolve the address conflict. Twice NAT technology rewrites both the source address and the destination address when a datagram passes between two areas connected by a twice NAT router.
To resolve address conflicts, Twice NAT works as follows. If Host-A in the private area starts to communicate with Host-X in the public area,
-A sends a Host-X DNS address query packet. DNS-ALG (Domain Nam
e Service-Application Level Gateway) captures this packet, and Host-X
Address that can be routed in the private area (Host-X
PRIME) and return to Host-A. When DNS address resolution is complete, Host-A becomes Host-X
Start communication with PRIME. When this packet passes through Twice NAT, the source address is rewritten to the address that NAT has, and the destination address is rewritten to Host-X. The return packet from Host-X is also converted in the same way. DN above
Details of the operation of S-ALG are described in IETF RFC2694.
The above example is a technique used when the communication protocol of the network to which a certain terminal belongs and the network to which the communication partner terminal belongs are the same. If the communication protocol of the network to which a certain terminal belongs and the network to which the communication partner's terminal belongs are different, for example, a network using IPv4 as a protocol (hereinafter referred to as IPv4 network) and a network using Internet Protocol version 6 (hereinafter referred to as IPv6)
NAT-PT (IETF RFC2766), SOCKS64 (IETF RFC3)
089) and the like are known.
In either case, the IP packet format is basically converted between IPv4 and IPv6.
For example, an IPv4 address and an IPv6 address are converted. An apparatus that performs this conversion is hereinafter referred to as a translator. The translator needs to create and maintain the correspondence between IPv4 address and IPv6 address before conversion for conversion. When this correspondence is dynamically created each time communication occurs, DNS (Domain Name System) name resolution is used as an opportunity (ASCII Publishing, Internet RF
(See C Encyclopedia, pp323-329).
DNS is a system that converts human-friendly names (strings) such as web URLs into IP addresses. Hereinafter, the operation of converting a name to an IP address is called name resolution. Today, almost every application on the Internet uses this DNS to obtain the IP address of the other party.
Using this fact, NAT and translators constantly monitor DNS messages exchanged at the start of communication, and use name resolution request messages as a trigger for creating translation information (IP address correspondences, etc.). Specifically, when name resolution is performed for a certain name of an IPv6 terminal, if the response IP address is IPv4, the IPv4 address is rewritten to an IPv6 address and sent back to the IPv6 terminal.
Then, associate the rewritten IPv4 address with the rewritten IPv6 address.
In other words, DNS-ALG intercepts and rewrites the name resolution response message, and dynamically creates conversion information based on the information before and after this rewriting.

The IP packet has an IP header including packet transfer information, a TCP / UDP header, and application data. Translators represented by NAT and NAT-PT
Do not convert IP addresses included in application data.

On the other hand, as described above, SIP and SDP can set an IP address in application data.

However, when area A and area B are interconnected by an address translation device, and terminals belonging to area A and terminals belonging to area B perform communication by SIP, conventional NAT and translators use IP addresses set in SIP and SDP. There is a problem in that communication between terminals by SIP cannot be performed because no conversion is performed.
An object of the present invention is to provide a SIP message conversion method that enables communication between terminals by SIP even when a network to which a certain terminal belongs and a network to which a communication partner terminal belongs are different.

To solve the above problem, the present invention is a method for processing a message including a first part and a second part, comprising:
A first conversion process for converting information of the first portion from information according to the first protocol (or address system) to information according to the second protocol (or address system);
A process for determining whether the second part needs to be converted;
A second conversion process of converting information according to the first protocol into information according to the second protocol is performed on the information of the second portion determined to be necessary for conversion. The order of the first conversion process and the second conversion process is arbitrary.

These operations use the first server and the second server, and the first conversion process is the first.
And at least the second part information is transferred from the first server to the second server, and the second server extracts the parameters that need to be converted from the second part and is extracted For the parameter, the second conversion process is performed on the second server, and the second
The information of the second part subjected to the conversion process may be transferred from the second server to the first server.

Alternatively, a plurality of processors connected by an internal bus in a single server may jointly perform processing. A plurality of programs running on a single processor in a single server may perform processing together.

In a typical application, the first part is an IP header and the second part is S
A payload including an IP message, one of the first protocol and the second protocol is IPv4, the other is IPv6, and the information to be converted is an address.

The address translation device of the present invention is an address translation device connected to both the first network according to the first protocol and the second network according to the second protocol,
A storage unit that holds a conversion rule for converting the first protocol and the second protocol to each other, a first address according to the first protocol of the input information based on the conversion rule, and a second protocol A conversion unit that converts the protocol of the second address to each other; and a function of outputting the input information and the conversion rule.

The output destination is another server outside the apparatus, another block in the apparatus connected by the internal bus, or another processing block in the same processor.

In a preferred example, input information that has been subjected to protocol conversion using the input information and conversion rules at the output destination is re-input to the address conversion device.
In the present invention, an address translation device for connecting a network A according to a certain protocol P and a network B according to a certain protocol Q, the address translation device having an address translation function for mutually converting an address according to the protocol P and an address according to the protocol Q And a detection function for detecting communication according to a specific protocol, the address conversion function converts the address described in the first area of the communication data, and communication is detected when communication according to the specific protocol is detected. In order to convert the address described in the second area of the data, conversion information including the correspondence between the address in the protocol P and the address in the protocol Q is created.

More specifically, in a communication network interconnecting networks having different address systems, at least the following two means are provided in addition to the conventional address translation device represented by NAT or translator. That is, (1) means for detecting an SIP message transmitted / received between different areas by the address translation device, and (2) IP set in SIP and SDP.
SIP message conversion means for converting an address according to the address conversion method of the address conversion device is provided.
The address translation device sends the SIP message to the SIP server IP address or SI.
Detect by combination of P server IP address and port number, or port number. An address translator that interconnects networks with different address systems is a terminal or SI
When the SIP message transmitted from the P server is detected, the SIP message detecting means is activated.
The SIP message conversion means includes at least the following three functions. (1) SIP message conversion target parameter detection function, (2) Conversion rule corresponding to the address conversion method provided by the address conversion device, and (3) Function to rewrite SIP message using the conversion entry of the address conversion device. is there. The address translation device creates a translation entry based on the request of the SIP address translation device. Address translation device
Based on the conversion entry, the header information of the packet transmitted / received between the communication terminals is rewritten.
The function deployment method of the SIP message conversion means has the following three forms.
The first deployment method includes a SIP address conversion device including SIP message conversion means. The SIP address translation device rewrites the IP address included in the SIP message by using the translation entry of the address translation device.
In the second deployment method, the address translation device has a SIP message conversion target parameter detection function, and adds identification information (tag) to the conversion target parameter. The SIP address translation device has a function of rewriting the translation rule and the IP address included in the SIP message. The SIP address translator rewrites the IP address included in the SIP message using the translation entry of the address translator.
In the third deployment method, the address translation device includes SIP message translation means.
If the present invention is applied, IP included in SIP messages transmitted and received between different areas
The address information is converted using the conversion entry of the address conversion device. Therefore, it is possible to provide a voice communication service by VoIP between terminals belonging to different areas.
The communication network according to the present invention has the following features.
(1) In a communication network in which a network A conforming to a certain protocol P and a network B conforming to a certain protocol Q are connected by an address translation device,
The address translation device has a function to mutually convert protocol P to protocol Q, and SIP
A function for detecting communication, information and communication means necessary for communicating with the server device,
In the case where SIP communication is detected, the server device cooperates with the server device, and has a function of creating conversion information including the correspondence between the address in the protocol P and the address in the protocol Q,
The server device is necessary for communicating with the address conversion device, and conversion information and means necessary for mutually converting the protocols P and Q in the address conversion device when the information to be converted is included in the SIP communication. Information and communication means,
In SIP communication from network A according to protocol P to network B according to protocol Q, the address conversion device detects SIP communication, and the server device refers to the conversion information provided in the address conversion device by referring to the conversion information provided in the address conversion device. An address according to P is converted from an address according to protocol Q, and communication from network A according to protocol P to network B according to protocol Q refers to the conversion information provided in the address conversion device, and the address according to protocol P is determined according to protocol Q. A communication network characterized by converting to an address.

As described in (1) above, the address translator according to the present invention interconnects a network conforming to an IPv4 address and a network conforming to an IPv6 address, and the SIP address translator according to the present invention is a SIP.
If the IP address included in the message is rewritten, voice communication using SIP between terminals belonging to the IPv4 network and terminals belonging to the IPv6 network becomes possible.

As another aspect of the present invention, the address translation device according to the present invention interconnects the network 1 according to the IPv4 private address and the network 2 according to the IPv4 global address, and the SIP address translation device according to the present invention writes the IP address included in the SIP message. In other words, voice communication using SIP between the terminals belonging to the network 1 and the terminals belonging to the network 2 becomes possible. That is, the configuration is as shown in (2) below.
(2) In a communication network in which a plurality of networks A1, A2 conforming to a certain protocol P are connected by an address translation device,
The address translation device detects the SIP communication, the function to mutually convert the protocol P of the network A1 to the protocol P of the network A2, the function to detect SIP communication, the information and communication means necessary for communicating with the server device In this case, in cooperation with the server device, the function of creating conversion information including the correspondence between the address in the network A1 and the address in the network A2,
The server device includes conversion information and means necessary for mutually converting the address on the network A1 and the address on the network A2 in the address conversion device when the information to be converted is included in SIP communication, and the address conversion It has necessary information and communication means to communicate with the device,
In the SIP communication from the network A1 to the network A2, the address conversion device detects the SIP communication, and the server device refers to the SIP communication information from the address in the network A1 by referring to the conversion information provided in the address conversion device. The communication from the network A1 in accordance with the protocol P to the network A2 in accordance with the protocol P is converted from the address in the network A1 to the address in the network A2 by referring to the conversion information provided in the address conversion device. A communication network characterized by conversion.
(3) The address conversion device further has a function of detecting conversion target information included in SIP communication and adding identification information, and the server device detects the conversion target using the identification information. The communication network according to (1) or (2).
(4) The address conversion device further has a function of associating identification information with SIP communication information, and the address conversion device further has a function of deleting conversion information corresponding to the identification information when SIP communication ends. The communication network according to (3).
(5) The communication according to any one of (1) to (4), wherein the address conversion device detects SIP communication based on destination information or destination information and its port information or port information. network.
(6) In a communication network in which a network A conforming to a certain protocol P and a network B conforming to a certain protocol Q are connected by an address translation device,
The address translation device has a function to mutually convert protocol P to protocol Q, and SIP
A function to detect communication, a function to create conversion information including correspondence between addresses in protocol P and addresses in protocol Q, and protocol P and Q are converted to each other when conversion target information is included in SIP communication And means for generating conversion information necessary to
In the SIP communication from the network A according to the protocol P to the network B according to the protocol Q, the address conversion device detects the SIP communication, and the SIP communication information refers to the address according to the protocol Q from the address according to the protocol P with reference to the conversion information. Further, the communication from the network A according to the protocol P to the network B according to the protocol Q is characterized in that the address according to the protocol P is converted from the address according to the protocol P with reference to the conversion information included in the address conversion device. Communication network.
(7) In a communication network in which a network A1 and a network A2 conforming to a certain protocol P are connected by an address translation device,
The address translation device creates translation information including the function of mutually converting the protocol P of the network A1 into the protocol P of the network A2, the function of detecting SIP communication, and the correspondence between the addresses of the network A1 and the addresses of the network A2. A function and means for generating conversion information necessary to mutually convert the address of the network A1 and the address of the network A2 when the conversion target information is included in the SIP communication,
In SIP communication from network A1 to network A2, the address translation device detects SIP communication and SIP
The communication information is converted from the address of the network A1 to the address of the network A2 by referring to the conversion information. Further, the communication from the network A1 to the network A2 is performed by referring to the conversion information included in the address conversion device. A communication network characterized by converting the address of A1 to the address of network A2.

Features of the server device embodying another aspect of the present invention are as follows.
(A) In a communication network in which a network conforming to a certain protocol P and a network conforming to a certain protocol Q are connected by an address translation device,
The address translation device has a function to mutually convert protocol P to protocol Q, and SIP
A function for detecting communication, information and communication means necessary for communicating with the server device,
In the case where SIP communication is detected, the server device cooperates with the server device, and has a function of creating conversion information including the correspondence between the address in the protocol P and the address in the protocol Q,
Translation information and means necessary for mutual conversion of protocols P and Q in the address translation device when the information to be translated is included in SIP communication, and information and communication means necessary for communication with the address translation device A server device comprising:
(B) In a communication network in which a plurality of networks A1 and A2 conforming to a certain protocol P are connected by an address translation device,
The address translation device detects the SIP communication, the function to mutually convert the protocol P of the network A1 to the protocol P of the network A2, the function to detect SIP communication, the information and communication means necessary for communicating with the server device In this case, in cooperation with the server device, the function of creating conversion information including the correspondence between the address in the network A1 and the address in the network A2,
In order to communicate with the address translation device, the translation information and means necessary for mutually converting the address on the network A1 and the address on the network A2 in the address translation device when the information to be translated is included in the SIP communication A server apparatus comprising information necessary for communication and communication means.

The address translation device of the present invention is
(1) An address translation device for connecting a network A conforming to a certain protocol P and a network B conforming to a certain protocol Q,
A conversion function for mutually converting the protocol P and the protocol Q;
A communication function for communicating with the server device;
A conversion information creating function for creating conversion information including a correspondence relationship between an address in protocol P and an address in protocol Q;
An address conversion device, wherein the detected SIP communication data is transferred to the server device, and the server device receives SIP communication data whose protocols are mutually converted based on the conversion information.
(2) In a communication network in which a plurality of networks A1, A2 conforming to a certain protocol P are connected by an address translation device,
The server device includes conversion information and means necessary for mutually converting the address on the network A1 and the address on the network A2 in the address conversion device when the information to be converted is included in the SIP communication, and the address conversion device. With necessary information and communication means to communicate with
The function of mutually converting the protocol P of the network A1 into the protocol P of the network A2, the function of detecting the SIP communication, the information and communication means necessary for communicating with the server device, and the above when the SIP communication is detected An address translation device comprising a function of creating translation information including a correspondence relationship between an address on the network A1 and an address on the network A2 in cooperation with the server device.
(3) The address translation device according to claim 1 or 2, further comprising a function of detecting information to be converted included in SIP communication and adding identification information.
(4) The address conversion device further has a function of associating identification information with SIP communication information, and the address conversion device further has a function of deleting conversion information corresponding to the identification information when SIP communication ends. The address conversion device according to (3).
(5) The address conversion device as described above, wherein SIP communication is detected based on destination information or destination information and its port information or port information.
(6) In a communication network in which a network A conforming to a certain protocol P and a network B conforming to a certain protocol Q are connected by an address translation device,
It has a function to mutually convert protocol P to protocol Q, a function to detect SIP communication, and a function to create conversion information including the correspondence between addresses in protocol P and addresses in protocol Q.
When the conversion target information is included in the SIP communication, there is provided means for generating conversion information necessary for mutually converting the protocols P and Q, and rewriting the content of the communication with reference to the conversion information. Address translation device.
(7) In a communication network in which a network A1 and a network A2 conforming to a certain protocol P are connected by an address translation device,
A function to mutually convert the protocol P of the network A1 to the protocol P of the network A2, a function to detect SIP communication, and a function to create conversion information including the correspondence between the addresses of the network A1 and the addresses of the network A2 ,
A means for generating conversion information necessary for mutually converting the address of network A1 and the address of network A2 when conversion target information is included in SIP communication,
When the conversion target information is included in the SIP communication, there is provided means for generating conversion information necessary for mutually converting the address of the network A1 and the address of the network A2, and rewriting the contents of the communication with reference to the conversion information. An address translation device characterized by that.
(8) The address converter according to (7), wherein SIP communication is detected based on destination information, or destination information and its port information, or port information.

As is clear from the above embodiments, the present invention is such that the SIP address translation device 2
By rewriting the contents of the message using the conversion information of the address conversion device 1, voice communication by SIP between terminals existing in different areas is made possible. The address translation device 1 has a function of detecting a conversion target parameter of the SIP message,
If identification information (tag) is given to the conversion target parameter, the SIP address conversion device 2
Can be reduced. Furthermore, if the address translation device 1 has a function of detecting the correspondence between the identification information and the call leg and the start and end of the SIP session, the address translation device 1 can delete the corresponding entry at the end of communication. Therefore, finer SIP communication control becomes possible.

If the address translation device 1 includes SIP message translation means, communication processing with the SIP message translation device 2 can be omitted.

  A first embodiment of the present invention will be described with reference to the drawings.

FIG. 1 shows a configuration example of a SIP communication network according to the present invention. In this embodiment, the SIP communication network includes a network A7 and a network B8. Each SIP communication network includes a SIP server 5, a terminal 6, and a DNS server 4. In this embodiment, the network A7 uses an IPv6 address. In this embodiment, the network B8 uses an IPv4 address. The network A7 and the network B8 are connected by the address translation device 1.

The address translation device 1 includes an IPv6 address / IPv4 address translation function, SIP message detection means, means for communicating with the SIP address translation apparatus 2, and means for communicating with the DNS-ALG 3.

The SIP address translation device 2 includes means for managing information necessary for address translation of the SIP message and rewriting the contents of the SIP message.

FIG. 6 shows the SIP protocol stack and message format. A packet including SIP is composed of an IP header 41, a TCP / UDP header 42, and a payload 43. The SIP is stored in the payload 43. SIP uses start-line44, message-header45 and message
Consists of -body46. Start-line 44 indicates the type and destination of the SIP message. Me
The ssage-header 45 includes a SIP parameter. Message-body 46 indicates connection information logically set between terminals. SDP etc. are used for the description of Message-body.

FIG. 7 shows a protocol stack for SIP communication between terminals belonging to different areas according to the present invention. SIP server 5 and terminal 6 are connected to SIP protocol stack (41, 42, 43) shown in FIG.
Is provided. In the present embodiment, the address translation device 1 performs the IP header 41 translation processing (47), and the SIP address translation device 2 performs the SIP message translation processing (48).

FIG. 2 shows a configuration example of the address translation device 1. The address translation device 1 is connected to a line (
18a, 18b, 18n), an interface unit (IF) (19a, 19b, 19n), a packet transfer processing unit 14, and a packet transfer control unit 13.

The packet transfer processing unit 14 includes a distribution processing unit 15 that detects a SIP message, a conversion information storage unit 16 that stores information necessary for address conversion, and a packet conversion / processing unit 17 that converts a data packet. Prepare. The conversion information storage unit 16 includes a conversion information table 500.

FIG. 19 shows an example of the table configuration of the conversion information table 500. Conversion information table 5
00 stores the correspondence between the IPv4 address 501 and the IPv6 address 502.

Returning to FIG. 2, the description of the address translation device 1 will be continued. The distribution processing unit 15 that detects the SIP message is transmitted and received between the network A7 and the network B8 by any of the following means:
Detect SIP messages.

When the destination of the SIP message from the network A (network B) to the network B (network A) is limited, the address translation device 1 detects the SIP message with the destination address of the packet header. The distribution processing unit 15 of the address translation device 1 stores the address information of the SIP message destination.

The address translation device 1 may detect the SIP message by a combination of the destination address and the destination port number in the packet header. T for transport mechanism
When using CP or UDP, the default port number for SIP is 5060.

When the destination of the SIP message from network A (network B) to network B (network A) is not limited, the address translation device 1 detects the SIP message with the destination port number in the packet header. The distribution processing unit 15 of the address translation device 1 includes port number information used for SIP communication.

When receiving the IPv4 packet, the packet conversion / processing unit 17 searches the conversion information storage unit 16 and rewrites the IPv4 address into the IPv6 address. Further, when receiving the IPv6 packet, the packet conversion / processing unit 17 searches the conversion information storage unit 16 and rewrites the IPv6 address into the IPv4 address. At this time, it is possible to rewrite various information in addition to the IP address.
FIG. 4 shows the IPv4 packet format.
FIG. 5 shows the IPv6 packet format. When converting, not only the IP address but also this format is converted.

Returning to FIG. 2, the description of the address translation device 1 will be continued. The packet transfer control unit 13 includes a conversion entry registration processing unit 11 and a conversion entry generation processing unit 12.
The conversion entry registration processing unit 11 registers the conversion information in the conversion information storage unit 16.
The conversion entry generation processing unit 12 has a function of generating address conversion information.

FIG. 3 shows a configuration example of the SIP address translation device 2. The SIP address translation device 2 includes an interface unit (IF) (23a, 23b) that accommodates lines (24a, 24b), a memory 22, and a CP
It is configured to connect U21 to the bus 25.

The memory 22 stores a SIP message conversion processing program 26, a conversion information inquiry processing program 27, and a conversion rule storage unit 28.

The SIP message conversion processing unit 26 includes the conversion target parameter information table 412 shown in FIG. 25 and the SIP message processing routine 60 shown in FIG. 18, and converts the address information included in the SIP message.

FIG. 25 shows an information table 412 including a conversion target parameter list. In this table, SIP and SDP parameters that can set IP addresses and port numbers are defined.

The conversion rule storage unit 28 stores parameter conversion rules for each address conversion method provided in the address conversion device 1. The address included in the SIP message is converted according to the conversion rule.
FIG. 26 shows a translation rule 413 when the address translation apparatus 1 performs address translation by the NAT-PT method. By storing the conversion rules 413 necessary for SIP message conversion in the memory, the conversion process is speeded up.

The conversion information inquiry unit 27 performs a process of inquiring the address conversion device 1 for IP address conversion information.

A case will be described in which the terminal 6a of the network A in FIG. 1 performs voice communication using the SIP with the terminal 6b of the network B in accordance with the sequence shown in FIGS. At the start of communication, it is necessary to establish a session between the terminal 6a and the terminal 6b.

Here, it is assumed that the SIP server 5a is set as the transmission destination of the SIP message in the terminal 6a.

The terminal 6a transmits INVITE requesting establishment of a session with the terminal 6b to the SIP server 5a (101).
FIG. 8 shows an example INVITE message 401 transmitted from the terminal 6a to the SIP server 5a. Start-L
Inine, INVITE destination information is set. The Via header indicates the route of the SIP Request. A response to the SIP Request is transmitted from the receiving terminal to the calling terminal based on the via header information. The To header indicates the request destination, the From header indicates the request initiator, and Call-ID indicates the call identifier. The c parameter of Message-body indicates connection information, and the m parameter indicates a port number for receiving data. After the session is established, the voice information between the terminals is transmitted to the c parameter and the m parameter.

Returning to FIG. 27, the description of the sequence is continued. When SIP server 5a receives INVITE, I
The NVITE destination is determined from the start-line destination information. When the domain name is set in the destination information, the SIP server 5a sends a DNS inquiry to the DNS server 4a (1
02). The DNS server 4a resolves the name of the SIP server 5b in cooperation with the DNS-ALG 3 and the DNS server 4b (103). For example, the address translation method described in Japanese Patent Application Publication No. 2001-274419 is applied to the linkage method between the address translation device (TR) 1 and DNS-ALG3. DNS-ALG3
Converts the IPv4 address b4 for the domain name of the SIP server 5b to a virtual IPv6 address vb6. The conversion information is stored in the conversion information table 500 of the conversion information storage unit 16 of the address conversion device 1.

The SIP server 5a uses the virtual IPv6 address vb of the SIP server 5b as INVITE destination information.
6 is acquired (104), and the INVITE is transmitted to the virtual IPv6 address vb6 (105).
FIG. 9 shows a message example of the SIP message (INVITE) transmitted by the SIP server 5a.

The address translation device 1 sends a SIP message (INVITE) to an IP address or I
Detect by combination of P address and port number or port number (106)
. The address translation device 1 transmits the detected SIP message (INVITE) together with information indicating the address translation method to the SIP address translation device (SIP-ALG) 2 (107). When the address conversion device 1 has one address conversion method, information on the address conversion method may be set in the SIP address conversion device in advance.

When the SIP address conversion device 2 receives the SIP message, it starts the SIP message conversion processing routine 60 shown in FIG. 18 (108).

FIG. 18 shows a SIP message conversion processing routine 60 in the first embodiment. SI
The P address conversion device 2 compares the conversion target parameter list 412 with the received SIP message, and extracts the conversion target parameters (61).

If there is a parameter to be converted, it is checked whether the extracted parameter contains an IP address (62).

If the extracted parameter includes an IP address, the address conversion method is determined (63). Next, referring to the conversion rule 413 in the conversion rule storage unit 28, the IP address to be converted is specified (64). For example, when the INVITE shown in FIG. 9 is received, the IP addresses to be converted are the IPv6 address sipa6 of the SIP server 5a and the IPv6 address a6 of the terminal 6a.

If the address translation method of the address translation device 1 is masquerading, the port number included in the extracted parameter is also subject to translation.

The conversion information inquiry unit 27 of the SIP address conversion device 2 performs the conversion target IP address “sip
An address inquiry request 600 including “a6, a6” is transmitted to the address translation device 1 (6
5, 109).

FIG. 16 shows a message format of the address inquiry request 600. The address inquiry request is composed of a header portion 601 and request contents 602. Header part 601 is I
D (605) is provided for associating an address inquiry request with its response. Count (608
) Is the number of IP addresses to be converted.

Request content 602 is IP address type (IPv4, IPv6) for each IP address to be converted (60
9), a translation target IP address (610), and a translation target port number (611). The port number 611 is set when the port number is a conversion target.

The address translation device 1 receives the address inquiry request 600 and searches the translation information table 500 of the translation entry generation processing unit 12 using the translation target IP address.
If the translation target IP address exists in the translation information table 500 of the translation entry generation processing unit 12, the address translation device 1 sends an address inquiry request response (110, 66) including the translated IP address to the SIP address translation device 2. To do.
If the conversion target IP address does not exist in the conversion information table 500 of the conversion entry generation processing unit 12, the conversion entry registration processing unit 11 is activated and a conversion entry is set in the conversion information table 500 of the conversion information storage unit 16. The address translation device 1 transmits an address inquiry request response (110, 66) including the translated IP address “vsipa4, va4” to the SIP address translation device 2.

FIG. 17 shows a message format of the address inquiry request response 650.
The address inquiry request response includes a header part 601 and response contents 603. The response content 603 is a combination of the IP address type (620), IP address (621), port number (622) to be converted and the IP address type (623), IP address (624), and port number (625) after conversion. including.

The SIP address translation device 2 receives the address inquiry request response and rewrites the IP address information included in the SIP message (67, 111). More specifically, sipa6
To vsipa4 and a6 to va4.

The SIP address translation device 2 uses the SIP message (INVI
TE) is transmitted to the address translation device 1, and this routine is terminated (68, 112).

When the conversion target parameter is not extracted in step 61, and in step 62
If the IP address information is not included in the extraction parameter, SIP address converter 2
Does not rewrite SIP messages. SIP address translator 2 is address translator 1
SIP message is sent to (69), and this routine is terminated.

Returning to FIG. 27, the description of the sequence diagram is continued. When receiving the SIP message (INVITE) from the SIP address translation device 2 (112), the address translation device 1 performs address translation of the IP packet header including the SIP message (113). Address translation device 1
Referring to the conversion information table 500 of the conversion information storage unit 16, the destination address is the real IPv4 address “sipb4” of the SIP server 5b, and the source address is the virtual IPv4 of the SIP server 5a.
Each address is converted to “vsipa4”.

  FIG. 10 shows an example of a SIP message (INVITE).

  FIG. 11 shows an example of a SIP message (INVITE).

The SIP server 5b receives the SIP message (INVITE) shown in FIG. 10 (114). FIG.
Compared to the SIP message example before conversion shown in Fig. 9, via header, Call-ID h
IP address set in eader, Contact header, c parameter is changed from IPv6 to IPv6
Has been converted to 4.

The SIP server 5b identifies the location information of the receiving terminal 6b from the start-line destination information,
The SIP message (INVITE) shown in FIG. 11 is transmitted to the terminal 6b (115).

If the terminal 6b allows INVITE, the terminal 6b responds with 200 OK. The voice information transmitted from the terminal 6b to the terminal 6a is the IP address specified by the INVITE c parameter (the virtual IPv6 of the terminal 6a).
4 address “va4”) and the port number specified by the m parameter.

The SIP Response (200 OK) is transmitted to the terminal 6a via the SIP server on which the SIP Request has been processed based on the via header information.
FIG. 12 shows a SIP 200 OK message example 1.
FIG. 13 shows a SIP 200 OK message example 2.
Proceeding to FIG. 28, the SIP server 5b receives the SIP response (200 OK) shown in FIG.
Is received (121). The SIP server 5b transmits the SIP Response (200 OK) shown in FIG. 13 to the virtual IPv4 address “vsipa4” of the SIP server 5a (122). The address translator 1 detects the SIP message (200 OK) (123) and sends it to the SIP address translator 2 (124). The SIP address conversion device 2 that has received the SIP message activates a SIP message conversion processing routine 60. SIP message conversion process flow (125 to 128)
These are the same as steps 108 to 111 in FIG. The SIP address translation device 2 transmits an address inquiry request in which “vsipa4, va4, b4” is set in the translation target IP address to the address translation device 1 (126). The address translation device 1 searches the translation information table 500 of the translation entry generation processing unit 12 using the translation target IP address, and performs step 109.
The conversion entries “vsipa4-sipa6” and “va4-a6” generated at the time of reception are detected. The address translation device 1 generates a virtual IPv6 address “vb6” for “b4”, and
The information is stored in the conversion information table 500 of the conversion information storage unit 16. The address translation device 1
An address inquiry request response including a combination of the translation target IP address and the translated IP address is transmitted to the SIP address translation device 2 (127).
FIG. 14 shows a SIP 200 OK message example 3.
FIG. 15 shows a SIP 200 OK message example 4.

The SIP address translation device 2 rewrites the IP address information and SIP Response (200 O
K) is transmitted to the address translation device 1 (128, 129). Address translator 1 is SIP
IP packet header address conversion including Response is performed (130). Referring to the translation information table 500 of the translation information storage unit 16 of the address translation device 1, the destination address is the real IPv6 address “sipa6” of the SIP server 5a, and the source address is the virtual IPv6 address “vsipb6” of the SIP server 5b. Respectively. Address translator 1 is SIP
The SIP Response (200 OK) shown in FIG. 14 is transmitted to the server 5a (131). SIP server 5a
Transmits a SIP Response (200 OK) shown in FIG. 15 to the terminal 6a (132).

The voice information transmitted from the terminal 6a to the terminal 6b is the IP specified by the c parameter of 200 OK.
The address (the virtual IPv4 address “vb6” of the terminal 6b) and the port number specified by the m parameter are transmitted.
Proceeding to FIG. 29, when the terminal 6a receives a SIP Response (200 OK) to the INVITE, the terminal 6a transmits a response confirmation (ACK) to the SIP server 5a (141). The SIP server 5a transmits a response confirmation (ACK) to the virtual IPv4 address “vsipb6” of the SIP server 5b (142). The address translation device 1 detects a SIP message (ACK) (143) and transmits it to the SIP address translation device 2 (144).

The SIP message conversion process flow (145 to 148) is shown in steps 108 to 111 in FIG.
It is the same. The SIP address translator 2 sends a response confirmation (ACK) with the IP address information rewritten to the address translator 1 (149). The address translation device 1 translates the IP packet header address including the SIP message (ACK) (150). The address translation device 1 transmits an acknowledgment (ACK) to the real IPv4 address “sipb4” of the SIP server 5b (151). The SIP server 5b transmits a response confirmation (ACK) to the terminal 6b (152).

With the above procedure, a logical connection is set between the terminal 6a and the terminal 6b, and voice communication between the terminals becomes possible. Terminal 6a is a virtual IP corresponding to the IPv4 address of terminal 6b
A packet including voice information is transmitted to the v6 address (vb6) (153). The address translation device 1 has a translation information storage unit with a source IP address “a6” and a destination IP address “vb6”.
Search for 16. Then, the conversion entry registered in step 109 and step 126 of the above processing sequence is detected.
The address translator 1 rewrites the header information based on the translation entry (154)
. For the source IP address, a virtual IPv4 address “va4” corresponding to the IPv6 address “a6” of the terminal 6a is set. For the destination IP address, the actual IPv4 address of the terminal 6b "b4
"Is set. The address translation device 1 sends the packet obtained by converting the header information to the terminal 6b.
Send to address (155).
A packet including voice information transmitted from the terminal 6b to the terminal 6a is also processed in the same manner (156
~ 158).

According to the present invention, the IP address of the SIP message can be converted using the information of the address conversion device. Therefore, SIP communication between terminals belonging to different areas becomes possible.

  A second embodiment of the present invention will be described with reference to the drawings.

The first embodiment and the second embodiment differ in the function deployment method of the SIP message conversion means.

In the second embodiment, the address translation device 1 has a function of detecting a translation target parameter of a SIP message.

FIG. 20 shows a configuration example of the address translation device 1 in the second embodiment. The address translation device 1 in the second embodiment includes a packet transfer control unit 13 in addition to the configuration example of FIG.
The tag processing unit 20 is provided.

The tag processing unit 20 includes a conversion target parameter list 412 shown in FIG. 25 and a tag addition processing routine 80 shown in FIG. When the address translation device 1 detects the SIP message, it starts the tag assignment processing routine 80.
FIG. 22 shows a tag assignment processing routine 80 of the address translation device 1. The address translation device 1 compares the conversion target parameter list 412 with the received SIP message and extracts the conversion target parameters (81). When the conversion target parameter exists in the SIP message, the address conversion device 1 generates identification information (tag) and adds it to the detection parameter (82). The tag is composed of an address translation method and an identifier provided by the address translation device 1. The address translation device 1 transmits the SIP message to which the identification information is added to the SIP address translation device 2 (83), and ends this routine.
FIG. 21 shows a tagged SIP message example 410 transmitted from the address translation device 1 to the SIP address translation device 2. Compared to FIG. 8, it can be seen that a tag is added to the head of the line to be converted.
If the conversion target parameter does not exist in step 81, this routine is terminated.
When there is no conversion target parameter, the address conversion device converts the address information of the IP packet header including the received SIP message, and transfers the SIP message. SIP
The contents of the message are not converted.

In the second embodiment, the SIP address conversion device 2 includes a SIP message conversion processing unit 26.
SIP message conversion processing routine 70 is provided.

FIG. 23 shows a SIP message conversion processing routine 70 that is activated when the SIP address conversion device 2 receives a tagged SIP message in the second embodiment.

The difference between the SIP message conversion processing routine 70 of FIG. 23 and the SIP message conversion processing routine 60 in the first embodiment is that a tag-added parameter extraction step 69 exists instead of step 61. In step 69, tagged parameters are extracted from the received SIP message.

According to the embodiment of the present invention, the address translation device 1 has a SIP message translation target parameter detection function, so that the processing load on the SIP address translation device 2 can be reduced. If the received SIP message does not include the conversion target parameter, the address translation device 1 can transfer the SIP message without activating the SIP address translation device 2.

  A third embodiment of the present invention will be described with reference to the drawings.

The feature of the present embodiment is that tag information in the second embodiment is changed to call leg of SIP communication.
It is in matching with. Call leg indicates peer to peer SIP relationship.
Call leg can be uniquely identified by a combination of To header, From header, and Call-ID. The header is included in all SIP messages.
The address translation device 1 according to the present embodiment is similar to the address translation device 1 according to the second embodiment, further includes table information 300 for managing the correspondence between tags and call legs, and a table for managing the correspondence between tags and media information. Information 310 and method information indicating the start and end of the SIP session are provided. For example, BYE is a SIP method indicating a SIP session termination request.
Further, tag information is added to each entry of the conversion information table 500 included in the conversion entry generation processing unit 12 of the address conversion device 1.
In the present embodiment, the SIP address translation device 2 sets the tag information in the ID of the address inquiry request 600 transmitted to the address translation device 1. Address translation device 1
When generating the conversion entry, the tag information is stored in the conversion information table 500.
Normally, a SIP session termination request does not include a message-body. However, when providing finer SIP communication, it is desirable that the address translation device 1 deletes the address translation information of the corresponding session at the end of the session.
In the present embodiment, the address translation device 1 includes the correspondence information between the call leg and the tag, so that the corresponding translation information is deleted at the end of the session without the SIP address translation device 2 having a session state management function. Features.
FIG. 31 shows a tag management table 300 provided in the tag processing unit 20 of the address translation device 1 in this embodiment. Each entry in the tag management table 300 includes a tag (301) and an IPv6
To header (302), IPv6 From header (303), IPv6 Call-ID (304), IPv4 To h
Define eader (305), IPv4 From header (306), and IPv4 Call-ID (307).
Since IP address information can be set in To header, From header and Call-ID header, entries on the IPv6 side and IPv4 side are defined.
FIG. 32 shows the media information management table 310 provided in the translation entry generation processing unit 12 of the address translation device 1 in this embodiment. Each entry in the media information management table 310 includes a tag (311), an IPv6 side c parameter (312), and an IPv6 side m parameter (313).
), IPv4 side c parameter (314), and IPv4 side m parameter (315). The address translation device 1 includes the media information management table 310 to block the voice information after the session ends.

FIG. 30 shows a tag assignment processing routine 90 provided in the address translation device 1 in the third embodiment. When detecting the SIP message, the address translator 1 searches the tag management table 300 (91). The search key is the call leg of the received SIP message.
Information (To, From, Call-ID).

If no entry exists, a tag is generated (92).
The address translation device 1 refers to the method information indicating the start and end of the SIP session and the parameter list for translation 412 and performs processing according to the received message (93).

When the SIP message indicates the end of the session and the conversion target parameter exists in the SIP message, the address conversion device 1 converts the SIP message with the tag information into the SIP message.
The data is transmitted to the address translation device 2 (94). The address translation device 1 receives the SIP message with the parameters rewritten from the SIP address translation device 2 (95). Here, the conversion entry of the corresponding tag included in the conversion information table 500 of the conversion entry generation processing unit 12 and the entry of the corresponding tag included in the media information management table 310 are deleted. Further, the conversion entry registration processing unit 11 requests the conversion information storage unit 16 to delete the corresponding entry. When the conversion entry registration processing unit 11 ends normally, this routine ends (96).

If the SIP message indicates the end of the session and there is no conversion target parameter in the SIP message, the address translation device 1 executes step 96 described above.

When the SIP message indicates the start of a session, the address translation device 1 registers the correspondence information of the tag, c parameter, and m parameter in the media information management table 310 (97). If the conversion target parameter exists in the SIP message, the address conversion device 1 transmits the SIP message with the tag information added to the SIP address conversion device 2 (98
), This routine is terminated. If the parameter to be converted does not exist in the SIP message, this routine ends.

When the SIP message is other than the start end and the conversion target parameter exists in the SIP message, the address translation device 1 sends the SIP message with the tag information to the SIP address translation device 2 (98), and ends this routine. .

If the SIP message is other than a session start / end request and the conversion target parameter does not exist in the SIP message, this routine ends.

According to the sequence shown in FIGS. 33, 34 and 35, the network A terminal in the third embodiment
The case where 6a performs voice communication using the SIP with the terminal 6b of the network B will be described.

33 and 34 show a session establishment sequence. The basic processing flow is shown in Figure 27.
And the same as FIG.
The difference between FIG. 33 and FIG. 27 is that step 116 is added to FIG.
The difference between FIG. 34 and FIG. 28 is that step 133 is added to FIG.
In step 116 and step 133, the address translation device 1 identifies that the detected SIP message indicates session start, and associates the tag information with the correspondence information between the c parameter and the m parameter included in the detected SIP message in the media information management table. Store in 310.

FIG. 35 shows a session end sequence. The basic flow is the same as in FIGS. The terminal 6a transmits a SIP message (BYE) requesting termination of the session with the terminal 6b to the SIP server 5a (161). The SIP server 5a is the virtual server of the SIP server 5b.
A SIP message (BYE) is transmitted to the Pv6 address “vsipb6” (162). The address translator 1 detects this SIP message (BYE) and sends the tagged SIP message to SIP.
It transmits to the address translation device 2 (163, 164). SIP message conversion process flow (16
Steps 5 to 168) are the same as steps 108 to 111 in FIG.

When receiving the SIP message (BYE) in which the parameter including the IP address is rewritten from the SIP address converting device 2 (169), the address converting device 1 converts the address of the packet header including the SIP message (170). The address translation device 1 sends a SIP message (BYE) to the real IPv4 address “sipb4” of the SIP server 5b (171).
. The SIP server 5b transmits a SIP message (BYE) to the terminal 6b (172).

When the terminal 6b normally processes the BYE, the terminal 6b transmits a response 200 OK to the BYE to the SIP server 5b (173).

The SIP server 5b sends a response 200 OK to BYE to the virtual IPv4 address “v” of the SIP server 5a.
It is sent to “sipa4” (174).
The address translation device 1 that has detected the SIP message detects that the received SIP message is a response to the end of the session (175), and sends the tagged SIP message to the SIP address translation device 2 (176). SIP message conversion process flow (17
7 to 180) are the same as steps 108 to 111 in FIG.

When the address translator 1 receives the SIP message (BYE) whose parameters have been rewritten from the SIP address translator 2 (181), the address translator 1 translates the address of the packet header including the SIP message. Next, the address translation device 1 includes a tag management table 30.
The tag is searched using 0 as the search key for call leg information of the SIP message. Next, the conversion entry of the corresponding tag included in the conversion information table 500 and the entry of the corresponding tag included in the media information management table 310 are deleted (182).
The address translation device 1 transmits a SIP message (BYE) to the terminal 6b via the SIP server 5b (183, 184).

According to the embodiment of the present invention, the address translation device 1 has a correspondence relationship between a tag and a call leg, so that the translation entry can be deleted at the end of SIP communication.

  A fourth embodiment of the present invention will be described with reference to the drawings.

The present embodiment is characterized in that the IP address conversion device 1 includes SIP message conversion means.

  FIG. 24 shows a configuration example of the address translation device 1 in this embodiment.

The packet transfer control unit 13 includes a SIP message conversion processing unit 31 and a conversion rule storage unit 32 in addition to the functional blocks of the address conversion device 1 in the first embodiment.

The SIP message conversion processing unit 31 has a function provided in the SIP message conversion processing unit 26 of the SIP address conversion device 2 in the first embodiment.

The conversion rule storage unit 32 has a function provided in the conversion rule storage unit 28 of the SIP address conversion device 2 in the first embodiment.

According to the embodiment of the present invention, communication processing with the SIP address translation device 2 can be omitted by providing the address translation device 1 with SIP message translation means. Therefore, it is possible to increase the processing speed associated with SIP message conversion.

  A fifth embodiment will be described.

In FIG. 1, network A7 uses an IPv4 private address. Network B8 uses IPv4 global addresses.

The address translator 1 uses IP instead of the IPv4 address and IPv6 address translation function.
Equipped with v4 private address and IPv4 global address conversion function.

In this embodiment, the address translation device 1 that has received the SIP message from the IPv4 private network 7 transmits the SIP message to the SIP address translation device 2. The SIP address conversion device 2 refers to the conversion rule and identifies the conversion target IP address. For example,
The addresses to be translated are the IPv4 private address of the SIP server 5a and the IPv4 of the terminal 6a.
Become a private address.

The SIP address translation device 2 transmits an address inquiry request including the translation target IP address to the address translation device 1.

The address translation device 1 that has received the address inquiry request creates a translation entry for the IPv4 private address and the IPv4 global address. The address translator 1 converts the IPv4 private address before translation into the SIP address translator 2 and I after translation.
An address inquiry request response including the Pv4 global address is transmitted.

According to the embodiment of the present invention, the network A7 and the network B8 according to the IPv4 protocol are interconnected by the address translation device 1, and the SIP address translation device 2 is included in the IP included in the SIP message.
If the address is rewritten, voice communication using the SIP of the terminal belonging to the network A7 and the terminal belonging to the network B8 becomes possible.

The block diagram which shows the structural example of the SIP communication network in this invention. 1 is a block diagram of an address translation device 1. FIG. The block diagram of the SIP address converter 2. FIG. IPv4 packet format diagram. IPv6 packet format diagram. SIP message format diagram. The protocol stack figure in this invention. The figure of SIP INVITE message example 1. The figure of SIP INVITE message example 2. The figure of SIP INVITE message example 3. The figure of SIP INVITE message example 4. The figure of SIP 200 OK message example 1. The figure of SIP 200 OK message example 2. The figure of SIP 200 OK message example 3. The figure of SIP 200 OK message example 4. The message format figure of an address inquiry request. The message format figure of an address inquiry request response. The SIP message conversion process routine figure with which the SIP address conversion apparatus 2 is provided. The conversion information table figure with which the address converter 1 is provided. The block diagram of the address translation apparatus 1 in the 2nd and 3rd Example of this invention. FIG. 9 is a diagram showing an example of a tagged SIP message in the second and third embodiments of the present invention. The tag provisioning process routine figure of the address translation apparatus 1 in 2nd Example of this invention. The SIP message conversion process routine figure of the SIP address conversion apparatus 2 in the 2nd and 3rd Example of this invention. The block diagram of the address translation apparatus 1 in the 4th Example of this invention. The SIP conversion object parameter list example figure in this invention. The SIP message conversion rule example figure in this invention. FIG. 1 is a SIP communication sequence diagram according to the present invention. FIG. 2 is a SIP communication sequence diagram according to the present invention. FIG. 3 is a SIP communication sequence in the present invention. The tag addition process routine figure of the address translation apparatus 1 in 3rd Example of this invention. The table figure of the tag management table in 3rd Example of this invention. The table figure of the media information management table in the 3rd Example of this invention. FIG. 1 is a SIP communication sequence diagram 1 according to a third embodiment of the present invention. FIG. 2 is a SIP communication sequence diagram 2 in the third embodiment of the present invention. FIG. 3 is a SIP communication sequence diagram 3 according to the third embodiment of the present invention.

Explanation of symbols

1 Address translator, 2 SIP address translator, 3 DNS-ALG, 5 SIP server, 6
Terminal, 41 IP header, 42 TCP / UDP header, 43 Payload, 51 Source IPv4 address, 52 Destination IPv4 address, 53 IPv4 payload, 54 Source IPv6 address, 55
Destination IPv6 address, 56 IPv6 payload, 60 SIP message conversion processing routine 1
70 SIP message conversion processing routine 2, 80 Tag assignment processing routine 1, 90 Tag assignment processing routine 2.

Claims (14)

A network according to a first protocol, a network according to a second protocol, and an address translation device connected to a server device,
A conversion unit that converts an address included in the first area of the received communication data from an address according to the first protocol to an address according to the second protocol;
Detecting means for detecting that the communication data follows a specific protocol;
When the detection means detects that the communication protocol conforms to a specific protocol, the address included in the second area of the communication data is converted from the address conforming to the first protocol to the address conforming to the second protocol. Means for creating conversion information;
A transmission / reception unit that transmits the communication data and the conversion information to the server device, and receives the communication data in which the address included in the second area is converted based on the conversion information from the server device; ,
When transmitting the communication data and the conversion information to the server device, the communication data is transmitted by attaching a tag to the parameter that needs to be converted among the parameters included in the second area. Address translation device. The detection means detects that the specified protocol is followed based on at least one of destination information, destination information and its port information, or port information included in the communication data. Item 2. The address translation device according to Item 1. 2. The address translation apparatus according to claim 1, wherein the specific protocol is SIP, the first area is an IP header, and the second area is a payload. 2. The address translation apparatus according to claim 1, wherein the first protocol is IPv4 and the second protocol is IPv6. 2. The address translation apparatus according to claim 1, wherein the first protocol is IPv6 and the second protocol is IPv4. 2. The address translation apparatus according to claim 1, wherein the address according to the first protocol is a private address, and the address according to the second protocol is a global address. 2. The address translation apparatus according to claim 1, wherein the address according to the first protocol is a global address, and the address according to the second protocol is a private address. A network according to the first address system, a network according to the second address system, and an address translation device connected to the server device,
A conversion unit that converts an address included in the first area of the received communication data from an address according to the first address system to an address according to the second address system;
Detecting means for detecting that the communication data follows a specific protocol;
When it is detected by the detection means that a specific protocol is followed, the address included in the second area of the communication data is converted from an address according to the first address system to an address according to the second address system. Means for creating conversion information for
A transmission / reception unit that transmits the communication data and the conversion information to the server device, and receives the communication data in which the address included in the second area is converted based on the conversion information from the server device; ,
When transmitting the communication data and the conversion information to the server device, the communication data is transmitted by attaching a tag to the parameter that needs to be converted among the parameters included in the second area. Address translation device. The detection means detects that the specified protocol is followed based on at least one of destination information, destination information and its port information, or port information included in the communication data. Item 9. The address conversion device according to Item 8. 9. The address translation apparatus according to claim 8, wherein the specific protocol is SIP, the first area is an IP header, and the second area is a payload. 9. The address translation apparatus according to claim 8, wherein the first address system is IPv4 and the second address system is IPv6. 9. The address translation apparatus according to claim 8, wherein the first address system is IPv6 and the second address system is IPv4. 9. The address translation apparatus according to claim 8, wherein the address according to the first address system is a private address, and the address according to the second address system is a global address. 9. The address translation apparatus according to claim 8, wherein the address according to the first address system is a global address, and the address according to the second address system is a private address.

Images