JP2007013332A - Network terminator, and communication processing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To sufficiently exert functions of a plurality of SIP servers having different specifications. <P>SOLUTION: Tables 21a, 21b, 21c register in advance responses for each specification of the SIP servers (a), (b) with respect to each state of an opposite apparatus and each state of a gateway itself for applying message processing to each of messages from the SIP servers (a), (b). Upon receipt of a message from the SIP server (a), a call control section 19d recognizes a state of the opposite apparatus or a state of the gateway itself with respect to the message processing, refers to the tables 21a, 21b, 21c, extracts a response in accordance with the specification of the SIP server (a) and the recognized state and transmits the response to the SIP server (a) which has transmitted the message. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a network termination device such as a gateway that receives a message from a SIP (Session Initiation Protocol) server and returns a response to the message, and a communication processing method thereof.

  The gateway connected to the IP network has a function of converting a voice signal or the like from a communication terminal into an IP packet and sending it to the IP network, or vice versa. Signal protocols used for IP networks include H.264. In recent years, the adoption rate of SIP, which has high affinity with protocols used on the Internet and high expandability, has been increased.

  This SIP is formulated by the Internet Engineering Task Force (IETF), which is an international standardization organization for Internet technology. As one of the standard documents, RFC (Request For Comments) shown in the following Non-Patent Document 1 is used. There are 3398.

  This RFC3398 describes that network termination devices such as gateways return the same response when receiving the same message from a plurality of SIP servers.

G. Camarillo Ericsson, 3 others, “Integrated Service Digital Network (ISDN) User Part (ISUP) to Session Initiation Protocol (SIP) Mapping”, P24-26, 46, December 2002, Network Working Group Request for Comments: 3398, [Search June 15, 2005] Internet <URL: http://www.ietf.org/rfc/rfc3398.txt>

  By the way, when a plurality of SIP servers are connected to a certain network, as described above, since SIP is highly extensible, specifications of SIP servers are often slightly different. For this reason, in the prior art, if the same response is returned to any SIP server, there is a problem that the function of each SIP server cannot be fully exhibited.

  The present invention has been made paying attention to such problems of the prior art, and an object of the present invention is to provide a network termination device capable of fully exhibiting the function of a SIP server and a communication processing method thereof. .

The invention relating to the network termination device for solving the above problems is as follows:
In a network termination device comprising network side transmission / reception means for transmitting / receiving to / from a network provided with a plurality of SIP servers having different specifications, receiving a message from the SIP server, and returning a response to the message,
A storage area in which responses for each specification of the plurality of SIP servers are stored for each state on the opposite device side for processing the message and for each state of the network termination device itself,
When the network side transmission / reception means receives the message from the SIP server, it recognizes the state of the opposite device side with respect to the processing of the message or the state of the network termination device itself, and refers to the contents stored in the storage area The SIP server that has sent the message extracts a response according to the specification and recognized state of the SIP server, and causes the network side transmission / reception means to transmit the response to the SIP server. Control means;
It is characterized by having.

Here, in the network termination device,
In the storage area, responses for each specification of the plurality of SIP servers may be stored for each of various incoming call impossible states on the opposite device side and for each of various incoming call impossible states of the network terminating device itself.

In the network termination device,
In the storage area, a connection destination address and a connection detour destination address are stored in association with each other,
When the network-side transmission / reception means sends a message to the connection destination and receives a response from the connection destination that the process indicated by the message cannot be executed, the call control means stores the contents stored in the storage area. The address of the connection detour corresponding to the connection destination that has sent the message may be extracted, and the message may be transmitted to the connection detour by the network side transmission / reception means.

The invention relating to the communication processing method of the network termination device for solving the above-mentioned problem,
In a communication processing method of a network termination device that receives a message from any of a plurality of SIP (Session Initiation Protocol) servers having different specifications and returns a response to the message,
Responses for each of the specifications of the plurality of SIP servers are registered in the storage area for each state on the opposite device side for the processing of the message and for each state of the network termination device itself,
When receiving a message from the SIP server, it recognizes the state of the opposite device side for the processing of the message or the state of the network terminating device itself, refers to the content stored in the storage area, For the SIP server that has been sent, extract the response according to the specifications of the SIP server and the recognized state,
Sending the extracted response to the SIP server that sent the message;
It is characterized by that.

  According to the present invention, since each of the plurality of SIP servers is dealt with according to the respective specifications, the functions of each SIP server can be sufficiently exhibited.

  Hereinafter, an embodiment of a communication system including a network termination device according to the present invention will be described with reference to the drawings.

  As shown in FIG. 1, the network termination device of this embodiment is a plurality of gateways 10a, 10b, and 10c connected to an IP (Internet Protocol) network 1. A PBX (Private Branch eXchange) 2 is connected to the first gateway 10a and the second gateway 10b, and a plurality of communication terminals 3 are accommodated in the PBX 2. In addition to a plurality of gateways 10a, 10b, and 10c, the IP network 1 is connected to a SIP server (a) 5a of an ISP (Internet Services Provider) 4a and a SIP server (b) 5b of an ISP 5b.

  The SIP server (a) 5a and the SIP server (b) 5b both employ SIP as a signal protocol, but the specifications of both servers are slightly different. Specifically, when the SIP server (a) 5a receives 486 (Busy Here) or 408 (Request Time Out) as a response from the gateway, a specification for making a detour call as described later is set. The server (b) 5b has a specification for making a detour call as described later when receiving a 600 (Busy Every Where) or 404 (Not Found) response from the gateway.

  As shown in FIG. 2, each gateway 10a, 10b, and 10c stores a CPU 11 that performs various calculations, a program memory 12 that stores programs executed by the CPU 11, and various data as shown in FIG. A data interface 13, a line interface 14 connected to a line such as a telephone line, and a LAN interface 15 connected to the LAN constituting the IP network 1.

  Further, each of the gateways 10a, 10b, and 10c has a software connection between a line control unit 17 that controls line connection with a telephone line and the like and a LAN that constitutes the IP network 1, as shown in FIG. LAN controller 19 to be controlled, timer controller 18, system controller 16 for managing the relationship between the controllers 17, 18, and 19, a configuration information storage unit 20 in which various types of configuration information are stored, ,have. The line control unit 17 includes a line interface 14, a program memory 12 in which various programs are stored, and a CPU 11 that executes programs stored in the memory 12, and a LAN control unit 19. Is configured to include a LAN interface 15, a program memory 12 in which various programs are stored, and a CPU 11 that executes the programs stored in the memory 12. Further, the system control unit 16 and the timer control unit 18 are configured to include the CPU 11 and the program memory 12, and the configuration information storage unit 20 is configured to include the data memory 13.

  The LAN control unit 19 includes an IP processing unit 19a that performs processing according to IP, a UDP processing unit 19b that performs processing according to UDP (User Datagram Protocol), a registration control unit 19c that manages location information, and SIP. A call control unit 19d that performs call control.

  In the configuration information storage unit 20, SIP response tables 21 a, 21 b, 21 c in which responses for each specification of the SIP server are stored for each of various factors, and connection destination addresses and connection detour destination addresses are associated with each other. And a detour destination table 22 stored in the memory. The data in each table is set from a maintenance terminal device (not shown) directly connected to each gateway 10a, 10b, 10c, or from the maintenance terminal device connected to the IP network 1, It is set via the network 1.

  The SIP response tables 21a, 21b, and 21c include the SIP response table 21a for the line disconnect reason code in which the response for each SIP server based on the line disconnect reason code factor is stored, and the incoming call restriction factor in the own device (gateway). There is a SIP response table 21b for an in-device incoming call restriction factor in which a response for each SIP server is stored, and a SIP response table 21c for a slide transmission factor in which a response for each SIP server due to a slide transmission factor is stored.

  In the SIP response table 21a for the line disconnect reason code, as shown in FIG. 4, when the disconnect reason code from the line side is, for example, # 17 (destination user busy), as a response to the SIP server (a) 5a, 486 (Busy Here) is registered, and 600 (Busy Every Where) is registered as a response to the SIP server (b) 5b. When # 18 (no arrival user response), 408 (Request Time Out) is registered as a response to the SIP server (a) 5a, and 404 (Not Found) is registered as a response to the SIP server (b) 5b. Has been.

  In addition, as shown in FIG. 5, the SIP response table 21b for the in-device incoming call restriction factor includes, as shown in FIG. (A) 486 (Busy Here) is registered as a response to 5a, and 600 (Busy Every Where) is registered as a response to the SIP server (b) 5b.

  In the SIP response table 21c for the slide transmission factor, as shown in FIG. 6, the fact that the slide transmission is performed when 484 (Address incomplete) is received as a response from the SIP server (a) 5a is registered. When 403 (Forbidden) is received as a response from the server (b) 5b, it is registered that slide transmission is performed.

  In the detour destination table 22, as shown in FIG. 7, a normal connection destination and a detour destination when the connection destination cannot be connected are registered for each called number.

  Next, the operation of the communication system according to the present embodiment will be described with reference to the sequence diagrams shown in FIGS.

  First, according to the sequence diagram shown in FIG. 8, when the first gateway 10a receives the INVITE message from the server (a) 5a and notifies the PBX 2 of the call setting, the disconnect reason code # 17 is sent from the PBX 2. The operation at that time will be described.

  When an INVITE message is transmitted from the server (a) 5a to the first gateway 10a (S100a), the UDP processing unit 19b of the first gateway 10a receives the message and outputs an incoming call notification to the call control unit 19d ( S101). When receiving this, the call control unit 19d outputs an incoming call notification to the line control unit 17 (S102), and the line control unit 17 requests the PBX 2 to perform call setting (S103). At this time, if the destination communication terminal 3 is busy, the PBX 2 transmits a disconnect reason code # 17 to the first gateway 10a (S104).

  When the line control unit 17 of the first gateway 10a receives this, it passes this disconnect reason code # 17 to the call control unit 19d (S105). Upon receiving the disconnect reason code # 17, the call control unit 19d refers to the SIP response table 21a for the line disconnect reason code shown in FIG. 4 and for the SIP server (a) corresponding to the disconnect reason code # 17. The response 486 is extracted (S106a), and this response 486 is passed to the UDP processing unit 19b (S107a). The UDP processing unit 19b passes this response 486 to the IP processing unit 19a, converts it into an IP packet, and transmits the response 486 from the IP processing unit 19a to the server (a) 5a (S108a). As described above, since the server (a) 5a is set to make a detour when receiving the response 486, when the response 486 is received, the predetermined detour destination, in this case, the second gateway, is set. The INVITE message is transmitted again with 10b as a detour destination (S109a). The second gateway 10b that has received this INVITE message requests the PBX 2 to set up a call (S112).

  Further, when receiving the response 486, the server (a) 5a transmits ACK to the first gateway 10a (S110a). When receiving the ACK, the UDP processing unit 19b of the first gateway 10a communicates the ACK reception to the call control unit 19d (S111).

  By the way, the server (a) 5a described above is set to make a detour when the response 486 is received, but has received the same response 600 (Busy Every Where) as the response 486 (Busy Here). Sometimes it is not set to make a detour. For this reason, the detour function of the server (a) 5a can be made to function by transmitting the response 486 from the first gateway 10a to the server (a) 5a.

  Next, according to the sequence diagram shown in FIG. 9, when the first gateway 10a receives the INVITE message from the server (b) 5b and notifies the PBX 2 of the call setting, the disconnect reason code # 17 is sent from the PBX 2. The operation at that time will be described.

  When the INVITE message is transmitted from the server (b) 5b to the first gateway 10a (S100b), the UDP processing unit 19b of the first gateway 10a receives the message. Thereafter, similarly to the sequence shown in FIG. 8, the processing from step 101 to step 105 is executed. Upon receiving disconnection reason code # 17 in step 105, call control unit 19d refers to SIP response table 21a for the line disconnection reason code shown in FIG. 4 and SIP server (b) corresponding to this disconnection reason code # 17. Response 600 is extracted (S106b), and this response 600 is passed to the UDP processing unit 19b (S107b). The UDP processing unit 19b passes this response 600 to the IP processing unit 19a, converts it into an IP packet, and transmits the response 600 from the IP processing unit 19a to the server (b) 5b (S108b). As described above, the server (b) 5b is set to make a detour when the response 600 is received. Therefore, when the response 600 is received, the server (b) 5b receives a predetermined detour destination, in this case, the second gateway. The INVITE message is transmitted again with 10b as a detour destination (S109b). The second gateway 10b that has received this INVITE message requests the PBX 2 to set up a call (S112).

  Further, when the server (b) 5b receives the response 600, the server (b) 5b transmits ACK to the first gateway 10a (S110b). When receiving the ACK, the UDP processing unit 19b of the first gateway 10a communicates the ACK reception to the call control unit 19d (S111).

  By the way, the server (b) 5b described above is set to make a detour when receiving the response 600 (Busy Every Where), but has received the same type of response 486 (Busy Here) as the response 600. Sometimes it is not set to make a detour. For this reason, the detour function of the server (b) 5b can be made to function by transmitting the response 600 from the first gateway 10a to the server (b) 5b.

  Next, according to the sequence diagram shown in FIG. 10, the operation when the first gateway 10a itself has an unacceptable factor when the first gateway 10a receives the INVITE message from the server (a) 5a will be described.

  When an INVITE message is transmitted from the server (a) 5a to the first gateway 10a (S100a), the UDP processing unit 19b of the first gateway 10a receives the message and outputs an incoming call notification to the call control unit 19d ( S101). The call control unit 19d is notified of the line state from the line control unit 17 constantly or periodically, and when all the lines with the PBX 2 are blocked when the incoming call notification is received, for example, FIG. The response 486 for the SIP server (a) corresponding to the busy line conversation is extracted (S120a) with reference to the SIP response table 21b for the in-device incoming call restriction factor shown in FIG. (S107a).

  Thereafter, similarly to the sequence shown in FIG. 8, the response 486 is transmitted to the server (a) 5a (S108a), the INVITE message is transmitted from the server (a) 5a to the detour second gateway 10b (S109a), and the server (a). ACK transmission from 5a to first gateway 10a (S110a), ACK reception communication from UDP processing section 19b of first gateway 10a to call control section 19d (S111), call setup request from second gateway 10b to PBX 2 (S112) Is executed.

  Next, according to the sequence diagram shown in FIG. 11, when the first gateway 10a receives an INVITE message from the server (b) 5b, the operation when the first gateway 10a itself has an incoming call impossible factor will be described.

  When an INVITE message is transmitted from the server (a) 5b to the first gateway 10a (S100b), the UDP processing unit 19b of the first gateway 10a receives the message and outputs an incoming call notification to the call control unit 19d ( S101). As described above, the call control unit 19d is notified of the line state constantly or periodically from the line control unit 17, and when the incoming call notification is received, for example, all the lines with the PBX 2 are blocked. For this, referring to the SIP response table 21b with respect to the intra-device incoming call restriction factor shown in FIG. 5, the response 600 for the SIP server (b) corresponding to all the accommodated line conversations is extracted (S120b). Is transferred to the UDP processing unit 19b (S107b).

  Thereafter, similarly to the sequence shown in FIG. 9, 600 transmission to the server (b) 5b (S108b), INVITE message transmission from the server (b) 5b to the detour destination second gateway 10b (S109b), and server (b) 5b ACK transmission from the first gateway 10a to the first gateway 10a (S110b), ACK reception communication from the UDP processing unit 19b of the first gateway 10a to the call control unit 19d (S111), a call setup request from the second gateway 10b to the PBX 2 (S112), Is executed.

  As described above, even when the first gateway 10a itself has an unacceptable factor as in the sequences shown in FIGS. 10 and 11, by returning a response corresponding to the specifications of the server (a) 5a and the server (b) 5b, The detour function which is the function of the server (a) 5a and the server (b) 5b can be made to function.

  Next, the operation when a SET UP message is received from the PBX 2, an INVITE message is transmitted to the server (a) 5a, and an incoming call impossible response is received from the server (a) 5a according to the sequence diagram shown in FIG. To do.

  For example, when the SET UP message having the called number “2” is transmitted from the PBX 2 and received by the line control unit 17 of the first gateway 10a (S200a), the line control unit 17 notifies the call control unit 19d of the outgoing call. Is sent (S201). Upon receiving this notification, the call control unit 19d passes an INVITE instruction to the UDP processing unit 19b (S202). Upon receiving this INVITE instruction, the UDP processing unit 19b passes the INVITE to the IP processing unit 19a, converts it into an IP packet, and sends an INVITE message to the server (a) 5a that is the connection destination when the called number is "2" (S202a). If the server (a) 5a determines that the destination address included in this INVITE message is incomplete, as shown in FIG. 6, a response 484 is sent to the first gateway 10a in response to the INVITE message. Return (S203a).

  When the UDP processing unit 19b of the first gateway 10a receives the response 484 via the IP processing unit 19a, it returns an ACK to the server (a) 5a (S205a) and sends a 484 reception notification to the call control unit 19d. (S204a). Upon receiving this 484 reception notification, the call control unit 19d refers to the SIP response table 21c for the slide transmission factor shown in FIG. 6 and determines whether or not this response 484 is a response that should be slide transmission (S206a). ). In this case, since the response 484 is registered in the SIP response table 21c as a response to be sent by slide, when the called number is “2” with reference to the detour table 22 in order to make a slide call. To the second gateway 10b (S207a).

  When the call control unit 19d determines the detour destination, the call control unit 19d passes the INVITE instruction to the UDP processing unit 19b again, and transmits the INVITE message to the second gateway 10b that is the detour destination via the UDP processing unit 19b and the IP processing unit 19a. (S208, 209).

  Upon receiving this INVITE message, the second gateway 10b sends the INVITE message to the server (a) 5a (S210).

  Next, according to the sequence diagram shown in FIG. 13, the operation when the SET UP message is received from the PBX 2, the INVITE message is transmitted to the server (b) 5b, and the response indicating that the incoming call cannot be received is received from the server (b) 5b. To do.

  For example, when the SET UP message with the called number “3” is transmitted from the PBX 2 and is received by the line control unit 17 of the first gateway 10a (S200b), the line control unit 17 sends a call notification to the call control unit 19d. Is sent (S201). Upon receiving this notification, the call control unit 19d passes an INVITE instruction to the UDP processing unit 19b (S202). Upon receiving this INVITE instruction, the UDP processing unit 19b passes the INVITE to the IP processing unit 19a, converts it into an IP packet, and sends an INVITE message to the server (b) 5b that is the connection destination when the called number is “3”. Transmit (S202b). When the server (b) 5b determines that the destination address included in this INVITE message is incomplete, as shown in FIG. 6, a response 403 is sent to the first gateway 10a in response to the INVITE message. Return (S203b).

  When the UDP processing unit 19b of the first gateway 10a receives the response 403 via the IP processing unit 19a, it returns an ACK to the server (b) 5b (S205b) and sends a 403 reception notification to the call control unit 19d. (S204b). When receiving the 403 reception notification, the call control unit 19d refers to the SIP response table 21c for the slide transmission factor shown in FIG. 6 and determines whether or not the response 403 is a response to be transmitted by the slide (S206b). ). In this case, since the response 403 is registered in the SIP response table 21c as a response to be sent by slide, when the called number is “3” with reference to the detour table 22 in order to make a slide call. Is determined in the second gateway 10b (S207b).

  In the same manner as in the sequence shown in FIG. 12, the following is the transmission of the INVITE instruction from the call control unit 19d (S208), the transmission of the INVITE message from the UDP processing unit 19b to the bypass second gateway 10b (S209), and the second gateway 10b. An INVITE message transmission (S210) is executed to the server (b) 5b.

  As described above, in the present embodiment, the gateway 10a deals with each of the SIP servers 5a and 5b according to the respective specifications, so that the functions of the respective SIP servers 5a and 5b can be sufficiently exhibited. .

It is a systematic diagram of the communication system in one Embodiment which concerns on this invention. It is a circuit block diagram of a gateway in one embodiment concerning the present invention. It is a functional block diagram of the gateway in one Embodiment concerning this invention. It is explanatory drawing which shows the structure of the SIP response table with respect to the line disconnection reason code in one Embodiment which concerns on this invention. It is explanatory drawing which shows the structure of the SIP response table with respect to the incoming call | requirement control factor in the own apparatus in one Embodiment which concerns on this invention. It is explanatory drawing which shows the structure of the SIP response table with respect to the slide transmission factor in one Embodiment which concerns on this invention. It is explanatory drawing which shows the structure of the detour destination table in one Embodiment which concerns on this invention. FIG. 10 is a sequence diagram showing an operation when an INVITE message is received from the SIP server (a) and an incoming call failure is returned from the opposite device side in the embodiment according to the present invention. FIG. 11 is a sequence diagram showing an operation when an INVITE message is received from the SIP server (b) and an incoming call failure is returned from the opposite device side in the embodiment according to the present invention. FIG. 7 is a sequence diagram showing an operation when an INVITE message is received from the SIP server (a) and an incoming call is impossible due to the conditions within the own apparatus in the embodiment according to the present invention. FIG. 11 is a sequence diagram showing an operation when an INVITE message is received from the SIP server (b) and an incoming call is impossible due to the conditions in the local apparatus in the embodiment according to the present invention. In one Embodiment which concerns on this invention, it is a sequence diagram which shows operation | movement when an incoming call impossible returns from the SIP server (a) of the opposing apparatus side. In one Embodiment which concerns on this invention, it is a sequence diagram which shows operation | movement when an incoming call impossible returns from the SIP server (b) of the opposing apparatus side.

Explanation of symbols

1: IP network, 2: PBX, 3: communication terminal, 5a: SIP server (a), 5b: SIP server (b), 10a, 10b, 10c: gateway, 17: line control unit, 19: LAN control unit, 19a: IP processing unit, 19b: UDP processing unit, 19c: registration control unit, 19d: call control unit, 20: configuration information storage unit, 21a: SIP response table for line disconnect reason code, 21b: in-device incoming call restriction factor SIP response table for 21, 21c: SIP response table for slide transmission factor, 22: Detour destination table

Claims (5)

A network end having network side transmission / reception means for transmitting / receiving to / from a network provided with a plurality of SIP (Session Initiation Protocol) servers having different specifications, receiving a message from the SIP server, and returning a response to the message In the device
A storage area in which responses for each specification of the plurality of SIP servers are stored for each state on the opposite device side for processing the message and for each state of the network termination device itself,
When the network side transmission / reception means receives the message from the SIP server, it recognizes the state of the opposite device side with respect to the processing of the message or the state of the network termination device itself, and refers to the contents stored in the storage area The SIP server that has sent the message extracts a response according to the specification and recognized state of the SIP server, and causes the network side transmission / reception means to transmit the response to the SIP server. Control means;
A network termination device comprising: The network termination device according to claim 1, wherein
In the storage area, responses for each specification of the plurality of SIP servers are stored for each incoming call impossible state on the opposite device side and for each incoming call disabled state of the network terminating device itself.
A network terminator characterized by that. The network terminating device according to any one of claims 1 and 2,
In the storage area, a connection destination address and a connection detour destination address are stored in association with each other,
When the network-side transmission / reception means sends a message to the connection destination and receives a response from the connection destination that the process indicated by the message cannot be executed, the call control means stores the contents stored in the storage area. The connection detour address corresponding to the connection destination that sent the message is extracted, and the network side transmission / reception means transmits the message to the connection detour destination.
A network terminator characterized by that. In a communication processing method of a network termination device that receives a message from any of a plurality of SIP (Session Initiation Protocol) servers having different specifications and returns a response to the message,
Responses for each of the specifications of the plurality of SIP servers are registered in the storage area for each state on the opposite device side for the processing of the message and for each state of the network termination device itself,
When receiving a message from the SIP server, it recognizes the state of the opposite device side for the processing of the message or the state of the network terminating device itself, refers to the content stored in the storage area, For the SIP server that has been sent, extract the response according to the specifications of the SIP server and the recognized state,
Sending the extracted response to the SIP server that sent the message;
A communication processing method for a network termination device. In the communication processing method of the network termination device according to claim 4,
In the storage area, a connection destination address and a connection detour address are associated and registered,
When a message is sent to the connection destination and a response indicating that the process indicated by the message cannot be executed is received from the connection destination, the connection that sent the message is referred to by referring to the contents stored in the storage area Extract the connection detour address corresponding to the destination,
Sending the message to the extracted connection detour address;
A communication processing method for a network termination device.

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