JP5211899B2 - IP telephone system, local call control server, IP telephone terminal, and communication method - Google Patents

Description

  The present invention relates to a session establishment technique in an IP telephone system.

Patent Document 1 discloses a VoIP (Voice over Internet Protocol) multiplexing apparatus capable of realizing a plurality of sessions with only one analog line. This VoIP multiplexing apparatus constitutes a dial-up network using an analog line with a VoIP gateway, and multiplexes voice signals from subordinate analog telephones into voice packets and transmits them to the dial-up network. Then, the VoIP gateway sends out the voice packet received from the VoIP multiplexer via the dial-up network to the IP telephone network.
JP 2004-343417 A

  According to the technique described in Patent Document 1, a plurality of sessions can be realized simultaneously with only one analog line. However, sessions exceeding the number of contracted lines with an IP telephone service provider that provides an IP telephone network cannot be realized simultaneously.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a technology capable of simultaneously establishing a session with the number of contracted lines or more with an IP telephone service provider that provides an IP telephone network. It is in.

  In order to solve the above-described problem, in the present invention, a local call control server of each local telephone system belongs to the local call control server among the local telephone systems connected to each other via the IP telephone network. Call control information is exchanged using a session managed by the IP telephone network and established with the local telephone system of the other party in cooperation with the IP telephone terminal in the telephone system. . As a result, a session that is not managed by the IP telephone network is established in this session.

For example, the IP telephone system of the present invention is an IP telephone system having a plurality of private telephone systems connected to each other via an IP telephone network,
The local telephone system is
A local call control server;
A plurality of IP telephone terminals accommodated in the local call control server;
A gateway for connecting a local telephone system to the IP telephone network,
The local call control server is:
A multiplexing request including call control information received from any of the IP telephone terminals is sent to another IP telephone terminal that is establishing a session with another local telephone system including the destination of the call control information. Call control information multiplexing request means for transmitting;
Call control information notifying means for notifying the call control information received from any of the IP telephone terminals to the other IP telephone terminal that is the destination of the call control information,
The IP telephone terminal
Call control information multiplexing means for multiplexing the call control information included in the multiplexing request received from the local call control server into the payload of a voice packet to be transmitted through the session being established;
Terminal information multiplexing means for multiplexing terminal information, which is identification information of the own IP telephone terminal, in a payload of a voice packet transmitted through the session being established;
Call control information separating means for separating call control information multiplexed in a payload of a voice packet received via the session being established, and transmitting the call control information to the local call control server;
Terminal information separating means for separating terminal information multiplexed in the payload of a voice packet received via the session being established;
Voice reproduction means for reproducing voice data stored in a payload of the voice packet when the terminal information separated by the terminal information separation means is terminal information of a communication partner of the own IP telephone terminal; ,
The gateway is
Multicast changing means for changing the destination address of a voice packet received from another local telephone system via the IP telephone network to a multicast address and transmitting it to the local telephone system to which the gateway belongs.

  According to the present invention, it is possible to simultaneously establish more sessions than the number of contracted lines with an IP telephone service provider that provides an IP telephone network.

  Embodiments of the present invention will be described below.

  FIG. 1 is a schematic diagram of an IP telephone system according to an embodiment of the present invention.

  As shown in the figure, the IP telephone system of the present embodiment is configured by connecting a plurality of local telephone systems 1 and a call control server 2 to each other via an IP telephone network 3.

  The call control server 2 is a SIP (Session Initiation Protocol) server operated by an IP telephone service provider that provides the IP telephone network 3.

  The local telephone system 1 includes a gateway (GW) 11 that connects the local telephone system 1 to the IP telephone network 3, a local call control server 12, an IP telephone terminal 13, a gateway 11, a local call control server 12, and an IP telephone. And a LAN 14 for connecting the terminals 13 to each other.

  The local call control server 12 is an SIP server that performs call control of each IP telephone terminal 13 in the local telephone system 1 belonging to the local call control server 12.

  The IP telephone terminal 13 establishes a session with the other party in cooperation with the local call control server 12 in the local telephone system 1 to which the own IP telephone terminal 13 belongs, and makes a call via this session.

  The gateway 11 changes the destination address to the multicast address and transmits the voice packet received from the IP telephone network 3 to the LAN 14 by multicast. This setting may be set in the gateway 11 in advance, or each time the local call control server 12 establishes a session via the call control server 2, the port of the gateway 11 used in this session is set. May be set.

  In FIG. 1, the local call control server 12 cooperates with the IP telephone terminal 13 in the local telephone system 1 belonging to the local telephone call control server 12 to establish a communication with the local telephone system 1 on the other party side. Establish a session. At this time, the number of sessions (called network management sessions) of the local telephone system 1 managed by the call control server 2 does not reach the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3. Then, a session is established via the call control server 2. On the other hand, if the number of network management sessions has reached the number of contracted lines, it is checked whether there is a network management session established with the local telephone system 1 on the other party side of the call. If there is a management session, call control information is exchanged using this network management session. As a result, a session that is not managed by the call control server 2 (referred to as a non-network management session) is established in the network management session.

  Next, the private call control server 12 will be described in detail.

  FIG. 2 is a schematic configuration diagram of the local call control server 12.

  As shown in the figure, the local call control server 12 includes a network IF unit 121, a terminal registration information storage unit 122, a network management session information storage unit 123, a non-network management session information storage unit 124, and a SIP processing unit 125. The unique message multiplexing request unit 126, the unique message receiving unit 127, the quality change request unit 128, and the main control unit 129.

  The network IF unit 121 is an interface for connecting to the LAN 14 and the IP telephone network 3, and includes protocols (TCP (Transmission Control Protocol), UDP (User Datagram Protocol), IP, Ethernet (registered trademark) below the transport layer. ) Etc.).

  The terminal registration information storage unit 122 stores terminal registration information (including a terminal ID, an extension number, and an IP address (local IP address)) of each IP telephone terminal 13 belonging to the local call control server 12. Yes.

  The network management session information storage unit 123 stores information on a network management session established with the local telephone system 1.

  FIG. 3A is a diagram schematically illustrating an example of registered contents in the network management session information storage unit 123. As illustrated, a record 1230 is registered in the network management session information storage unit 123 for each network management session established with the local telephone system 1. The record 1230 includes a field 1231 for registering a network management session ID, which is network management session identification information, and a field 1232 for registering the terminal ID of the IP telephone terminal 13 in the local telephone system 1 connected to the network management session. A field 1233 for registering a telephone number (party number information: a telephone number assigned by an IP telephone service provider that provides the IP telephone network 3) assigned to the private telephone system 1 of the call partner, and the private telephone system of the call partner A field 1234 for registering one IP address (partner IP address: global IP address), a field 1235 for registering the actual use status of this network management session (either “in use” or “end of use”), Have

  Here, the network management session ID may be defined using the session ID included in the message body of the INVITE message. Alternatively, the local call control server 12 may define it independently.

  The non-network management session information storage unit 124 stores information on non-network management sessions established with the local telephone system 1.

  FIG. 3B is a diagram schematically illustrating an example of registered contents in the non-network management session information storage unit 124. As illustrated, a record 1240 is registered in the non-network management session information storage unit 124 for each non-network management session established with the local telephone system 1. The record 1240 registers a field 1241 for registering an unmanaged network session ID, which is identification information of the unmanaged network session, and the terminal ID of the IP telephone terminal 13 in the local telephone system 1 connected to the unmanaged network session. A field 1242, a field 1243 for registering a telephone number (partner number information) assigned to the private telephone system 1 of the other party, a field 1244 for registering a session ID of a network management session used by this non-network management session, Have

  If the non-network management session is a session (extension) between the IP telephone terminals 13 in the local telephone system 1, the extension number of the other party is registered in the field 1243 of the corresponding record 1240. Since the session is not used, “NULL” is registered in the field 1244 of the corresponding record 1240. Further, the non-network management session ID may be defined by using the session ID included in the message body of the INVITE message. Alternatively, the local call control server 12 may define it independently.

  The SIP processing unit 125 processes the SIP message in accordance with an instruction from the main control unit 129.

  The unique message multiplexing request unit 126 notifies the IP telephone terminal 13 in the local telephone system 1 of the multiplexing request for the unique message including the SIP message according to the instruction of the main control unit 129.

  The unique message receiving unit 127 receives the unique message from the IP telephone terminal 13 in the local telephone system 1 and notifies the main control unit 129 of the SIP message stored in the unique message.

  The quality change request unit 128 notifies the IP telephone terminal 13 in the local telephone system 1 of a request for changing the quality (compression rate) of the voice data in accordance with an instruction from the main control unit 129.

  Then, the main control unit 129 controls the units 121 to 128 of the local call control server 12 in an integrated manner.

  FIG. 4 is a flowchart for explaining the operation of the local call control server 12.

  When the main control unit 129 receives the REGISTER message from the IP telephone terminal 13 in the local telephone system 1 via the network IF unit 121 and the SIP processing unit 125 (YES in S10), the terminal registration of the IP telephone terminal 13 is performed. Information registration processing is performed (S11).

  Specifically, the main control unit 129 registers terminal registration information including the IP address of the transmission source of the REGISTER message, the extension number and the terminal ID described in the REGISTER message in the terminal registration information storage unit 122. To do. Further, the 200 OK message is transmitted to the transmission source of the REGISTER message via the SIP processing unit 125 and the network IF unit 121.

  Further, when receiving the INVITE message from the SIP processing unit 125 or the unique message receiving unit 127 (YES in S12), the main control unit 129 performs outgoing / incoming processing described later (S13).

  Further, when receiving a BYE message from the SIP processing unit 125 or the unique message receiving unit 127 (YES in S14), the main control unit 129 performs a disconnection process described later (S15).

  FIG. 5 is a flowchart for explaining the outgoing / incoming call processing (S13) shown in FIG.

  First, the main control unit 129 refers to the terminal registration information storage unit 122 and checks whether or not the transmission source of the INVITE message is the IP telephone terminal 13 belonging to the local call control server 12 (S1301). If the transmission source of the INVITE message is the IP telephone terminal 13 belonging to the local call control server 12 (YES in S1301), the process proceeds to S1302, and is not the IP telephone terminal 13 belonging to the local call control server 12. If so (NO in S1301), the process proceeds to S1311.

  In step S1302, the main control unit 129 refers to the terminal registration information storage unit 122 and checks whether the destination of the INVITE message is the IP telephone terminal 13 belonging to the local call control server 12. If the destination of the INVITE message is not the IP telephone terminal 13 belonging to the local call control server 12 (NO in S1302), the process proceeds to S1305.

  On the other hand, when the destination of the INVITE message is the IP telephone terminal 13 belonging to the local call control server 12 (YES in S1302), the main control unit 129 passes through the SIP processing unit 125 and the network IF unit 121. This INVITE message is transferred to the destination of the INVITE message. Thereafter, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 to relay the SIP message exchanged between the transmission source and the transmission destination of the INVITE message. The extension transmission process for establishing a non-network management session between the IP telephone terminals 13 belonging to 12 is executed (S1303).

  Then, the main control unit 129 adds a record 1240 to the non-network management session information storage unit 124. The field 1241 of this record 1240 is a session ID outside network management, the field 1242 is the terminal ID of the IP telephone terminal 13 that is the source of the INVITE message, and the field 1243 is the extension number of the IP telephone terminal 13 that is the destination of the INVITE message. And “NULL” is registered in the field 1244 (S1304).

  In step S1305, the main control unit 129 checks the number of records 1230 registered in the network management session information storage unit 123, that is, the number of network management sessions currently established. If the number of network management sessions has reached the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3 (NO in S1305), the process proceeds to S1308.

  On the other hand, when the number of network management sessions has not reached the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3 (YES in S1305), the main control unit 129 causes the SIP processing unit 125 and the network IF unit 121 to Then, the INVITE message is transferred to the call control server 2. Thereafter, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 to perform call control between the IP telephone terminal 13 that is the transmission source of the INVITE message and the other private telephone system 1 that is the transmission destination. Network management external line transmission for establishing a network management session between the IP telephone terminal 13 belonging to the local call control server 12 and another local call control server 12 by relaying the SIP message exchanged via the server 2 Processing is executed (S1306).

  Then, the main control unit 129 adds a record 1230 to the network management session information storage unit 123. The field 1231 of this record 1230 is the network management session ID, the field 1232 is the terminal ID of the IP telephone terminal 13 that is the source of the INVITE message, and the field 1233 is another private telephone that is the destination of the INVITE message. The telephone number of the system 1 is registered in the field 1234, the IP address of the other local telephone system 1 that is the destination of the INVITE message, and “in use” is registered in the field 1235 (S1307).

  In S1308, the main control unit 129 refers to the network management session information storage unit 123, and determines whether the destination of the INVITE message is the record 1230 registered in the field 1233 or the field 1234, that is, the INVITE message Check whether there is already a network management session connected to the destination. If there is already a network management session connected to the destination of the INVITE message (YES in S1308), network management outside line transmission processing described later is performed (S1309).

  On the other hand, when there is no network management session connected to the destination of the INVITE message (NO in S1308), the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 to send a BUSY message to the source of the INVITTE message. A predetermined busy process such as replying is performed (S1310).

  In step S1311, the main control unit 129 determines whether the INVITE message is received via the unique message receiving unit 127 or the SIP processing unit 125. When the message is received via the unique message receiving unit 127 (“via the unique message receiving unit” in S1311), the network management outside line incoming call processing described later is performed (S1314).

  On the other hand, when it is received via the SIP processing unit 125 (“SIP processing unit” in S1311), the main control unit 129 belongs to the local call control server 12 via the SIP processing unit 125 and the network IF unit 121. The INVITE message is transferred to each IP telephone terminal 13. Thereafter, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 to communicate with the other local telephone system 1 that is the transmission source of the INVITE message and the IP telephone terminal 13 that is the transmission destination in response to the INVITE message. A network management session is established between the IP telephone terminal 13 belonging to the local call control server 12 and another local call control server 12 by relaying the SIP messages exchanged between them via the call control server 2. The network management outside line incoming call processing is executed (S1312).

  Then, the main control unit 129 adds a record 1230 to the network management session information storage unit 123. The field 1231 of this record 1230 is the network management session ID, the field 1232 is the terminal ID of the IP telephone terminal 13 that responds to the INVITE message, and the field 1233 is another private telephone system 1 that is the source of the INVITE message. Is registered in the field 1234, the IP address of the other local telephone system 1 that is the source of the INVITE message, and "in use" is registered in the field 1235 (S1313).

  FIG. 6 is a flowchart for explaining the network management outside line transmission processing (S1309) shown in FIG.

  First, the main control unit 129 selects the IP telephone terminal 13 (referred to as the relay terminal 13) that relays the SIP message from the IP telephone terminals 13 belonging to the local call control server 12 (S130900).

  Specifically, the usage status registered in the field 1235 of the network management session record 1230 retrieved from the network management session information storage unit 123 in S1308 of FIG. 5 is confirmed, and this usage status is “in use”. Then, the IP telephone terminal 13 specified by the terminal ID registered in the field 1232 of this record 1230 is selected as the relay terminal 13. On the other hand, if the use status is “use completed”, the record 1240 in which the session ID registered in the field 1231 of the record 1230 is registered in the field 1244 is searched from the non-network management session information storage unit 124. Then, any one record 1240 is selected from the retrieved records 1240, and the IP telephone terminal 13 specified by the terminal ID registered in the field 1242 of this record 1240 is selected as the relay terminal 13.

  Next, the main control unit 129 generates a unique message including the INVITE message received in S12. In addition, the main control unit 129 refers to the terminal registration information storage unit 122 and identifies the IP address of the relay terminal 13. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S130901).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S130902).

  In addition, the main control unit 129 returns a 100 Trying message to the transmission source of the INVITE message via the SIP processing unit 125 and the network IF unit 121 (S130903). The main control unit 129 then waits to receive a 100 Trying message from the destination of the INVITE message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127 (S130904).

  When the 100 Trying message from the destination of the INVITE message is received (YES in S130904), the main control unit 129 receives 180 Rinning from the destination of the INVITE message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127. It waits to receive a message (S130905). When receiving the 180Ringing message from the destination of the INVITE message (YES in S130905), the main control unit 129 transfers this 180Ringing message to the source of the INVITE message via the SIP processing unit 125 and the network IF unit 121 ( S130906).

  Next, when the main control unit 129 receives a 200 OK message from the destination of the INVITE message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127 (YES in S130907), the main control unit 129 This 200 OK message is transferred to the transmission source of the INVITE message via the network IF unit 121 (S130908). Then, the main control unit 129 waits to receive an ACK message from the source of the INVITE message via the network IF unit 121 and the SIP processing unit 125 (S130909).

  When receiving the ACK message from the source of the INVITE message (YES in S130909), the main control unit 129 generates a unique message including the ACK message, and multiplexes the unique message together with the IP address of the relay terminal 13 into the unique message. Notification is made to the activation request unit 126 (S130910).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S130911).

  Next, the main control unit 129 retrieves the record 1230 from the network management session information storage unit 123 using the terminal ID of the relay terminal 13 as a key. If the record 1230 cannot be retrieved, the record 1240 is retrieved from the non-network management session information storage unit 124 using this terminal ID as a key. Then, the session ID of the network management session to be used is acquired from the field 1231 of the record 1230 or the field 1244 of the record 1240 that has been searched.

  Then, the main control unit 129 adds a record 1240 to the non-network management session information storage unit 124. The field 1241 of this record 1240 is a session ID outside network management, the field 1242 is the terminal ID of the IP telephone terminal 13 that is the source of the INVITE message, and the field 1243 is another local address that is the destination of the INVITE message. The telephone number of the telephone system 1 and the session ID of the network management session to be used are registered in the field 1244 (S130912).

  Next, the main control unit 129 determines the quality of the voice data of the network management session to be used and the non-network management session using this network management session (S130913).

  Specifically, the number of non-network management sessions is measured by searching the network management session information storage unit 124 for a record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Also, the record 1230 in which the session ID of the network management session to be used is registered in the field 1231 is searched from the network management session information storage unit 123, and the usage status registered in the field 1235 of the record 1230 is checked. If the usage status is “in use”, the larger the total number of network management sessions and non-network management sessions to be used, the lower the quality of voice data (for example, network management sessions and network management to be used). The quality of the audio data is set so that the compression rate increases in proportion to the total number of outside sessions. On the other hand, if the usage status is “end of use”, the larger the total number of non-network management sessions, the lower the quality of voice data (for example, the compression rate increases in proportion to the total number of non-network management sessions). To), set the quality of the audio data.

  Next, the main control unit 129 refers to the network management session information storage unit 123 and sets the terminal ID registered in the field 1232 of the record 1230 in which the session ID of the network management session to be used is registered in the field 1231. Identify. Further, the non-network management session information storage unit 124 is referred to, and each terminal ID registered in the field 1242 of the record 1240 in which the session ID of the network management session to be used is registered in the field 1244 is specified. Then, the terminal registration information storage unit 122 is referred to, and the IP address of each IP telephone terminal 13 specified by these terminal IDs is specified. Then, the IP address is notified to the quality change request unit 128 together with the quality of the voice data determined in S130913.

  In response to this, the quality change request unit 128 sends a change request (quality change request) to the determined voice data quality to each IP telephone terminal 13 specified by these IP addresses via the network IF unit 121. ) Is transmitted (S130914).

  FIG. 7 is a flowchart for explaining the network management outside line incoming call processing (S1314) shown in FIG.

  First, the main control unit 129 selects the relay terminal 13 from among the IP telephone terminals 13 belonging to the local call control server 12 (S131400). Specifically, the IP address of the IP telephone terminal 13 that is the transmission source of the unique message in which the INVITE message is stored is acquired from the unique message receiving unit 127. Then, this IP address is determined as the IP address of the relay terminal 13.

  Next, the main control unit 129 transmits an INVITE message to each IP telephone terminal 13 belonging to the local call control server 12 via the SIP processing unit 125 and the network IF unit 121 (S131401).

  Next, the main control unit 129 generates a unique message including a 100 Trying message. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S131402).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S131403).

  Next, the main control unit 129 waits to receive a 180 Ringing message from each of the IP telephone terminals 13 belonging to the local call control server 12 via the network IF unit 121 and the SIP processing unit 125 (S131404). When the 180 Ringing message is received from each IP telephone terminal 13 (YES in S131404), the main control unit 129 generates a unique message including the 180 Ringing message. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S131405).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S131406).

  Next, the main control unit 129 waits to receive a 200 OK message from any IP telephone terminal 13 belonging to the local call control server 12 via the network IF unit 121 and the SIP processing unit 125 (S131407). . When the 200OK message is received from any IP telephone terminal 13 (YES in S131407), the main control unit 129 generates a unique message including the 200OK message. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S131408).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 is transmitted via the network IF unit 121 (S131409).

  In addition, the main control unit 129 passes through the network IF unit 121 and the SIP processing unit 125 to each IP phone terminal 13 belonging to the local call control server 12 and other than the transmission source of the 200 OK message. A CANCEL message is transmitted (S131410).

  Next, when the main control unit 129 receives an ACK message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127 (YES in S131411), the main control unit 129 passes through the SIP processing unit 125 and the network IF unit 121. The ACK message is transferred to the sender of the 200 OK message (S131414).

  Next, the main control unit 129 acquires the terminal ID of the relay terminal 13 by referring to the terminal registration information storage unit 122, and searches the network management session information storage unit 123 for the record 1230 using this terminal ID as a key. If the record 1230 cannot be retrieved, the record 1240 is retrieved from the non-network management session information storage unit 124 using this terminal ID as a key. Then, the session ID of the network management session to be used is acquired from the field 1231 of the record 1230 or the field 1244 of the record 1240 that has been searched.

  Then, the main control unit 129 adds a record 1240 to the non-network management session information storage unit 124. The field 1241 of this record 1240 contains the session ID outside network management, the field 1242 shows the terminal ID of the IP telephone terminal 13 that is the sender of the 200 OK message, and the field 1243 shows the sender of the INVITE message received in S12. The telephone number of a certain other local telephone system 1 and the session ID of the network management session to be used are registered in the field 1244 (S131413).

  Next, the main control unit 129 determines the quality of the voice data of the network management session to be used and the non-network management session using this network management session (S131414).

  Specifically, the number of non-network management sessions is measured by searching the network management session information storage unit 124 for a record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Also, the record 1230 in which the session ID of the network management session to be used is registered in the field 1231 is searched from the network management session information storage unit 123, and the usage status registered in the field 1235 of the record 1230 is checked. If the usage status is “in use”, the larger the total number of network management sessions and non-network management sessions to be used, the lower the quality of voice data (for example, network management sessions and network management to be used). Set the quality of the voice data so that the compression rate increases in proportion to the total number of outside sessions. On the other hand, if the usage status is “end of use”, the larger the total number of non-network management sessions, the lower the quality of voice data (for example, the compression rate increases in proportion to the total number of non-network management sessions). Set the audio data quality to

  Next, the main control unit 129 refers to the network management session information storage unit 123 and sets the terminal ID registered in the field 1232 of the record 1230 in which the session ID of the network management session to be used is registered in the field 1231. Identify. Further, the non-network management session information storage unit 124 is referred to, and each terminal ID registered in the field 1242 of the record 1240 in which the session ID of the network management session to be used is registered in the field 1244 is specified. Then, the terminal registration information storage unit 122 is referred to, and the IP address of each IP telephone terminal 13 specified by these terminal IDs is specified. Then, the IP address is notified to the quality change request unit 128 together with the quality of the voice data determined in S131414.

  In response to this, the quality change request unit 128 sends a change request (quality change request) to the determined voice data quality to each IP telephone terminal 13 specified by these IP addresses via the network IF unit 121. ) Is transmitted (S131415).

  FIG. 8 is a flowchart for explaining the cutting process (S15) shown in FIG.

  First, the main control unit 129 refers to the terminal registration information storage unit 122 and checks whether or not the source of the BYE message is the IP telephone terminal 13 belonging to the local call control server 12 (S1501). If the source of the BYE message is the IP telephone terminal 13 belonging to the local call control server 12 (YES in S1501), the process proceeds to S1502, and the source of the BYE message is sent to the local call control server 12. If it is not the IP telephone terminal 13 to which it belongs (NO in S1501), the process proceeds to S1511.

  In step S <b> 1502, the main control unit 129 refers to the terminal registration information storage unit 122 and checks whether the destination of the BYE message is the IP telephone terminal 13 belonging to the local call control server 12. If the destination of the BYE message is not the IP telephone terminal 13 belonging to the local call control server 12 (NO in S1502), the process proceeds to S1505.

  On the other hand, when the destination of the BYE message is the IP telephone terminal 13 belonging to the local call control server 12 (YES in S1502), the main control unit 129 passes through the SIP processing unit 125 and the network IF unit 121. This BYE message is transferred to the destination of the BYE message. Thereafter, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 to relay the SIP message exchanged between the transmission source and the transmission destination of the BYE message, so that the local call control server The extension disconnection process for disconnecting the non-network management session established between the IP telephone terminals 13 belonging to 12 is executed (S1503).

  Then, the main control unit 129 refers to the non-network management session information storage unit 124, registers the terminal ID of the BYE message transmission source in the field 1242, and registers the extension number of the BYE message transmission destination in the field 1243. Or the record 1240 in which the terminal ID of the BYE message transmission destination is registered in the field 1242 and the extension number of the transmission source of the BYE message is registered in the field 1243. Then, the searched record 1240 is deleted from the non-network management session information storage unit 124 (S1504).

  In S1505, the main control unit 129 refers to the network management session information storage unit 123, the terminal ID of the BYE message transmission source is registered in the field 1232, and the telephone number of the BYE message transmission destination in the fields 1233 and 1234. The record 1230 in which the IP address is registered is searched.

  When such a record 1230 cannot be retrieved, the session to be disconnected is a session outside network management. In this case (NO in S1505), the first network management outside line disconnection process described later is performed (S1506).

  On the other hand, if such a record 1230 can be retrieved, the session to be disconnected is a network management session. In this case (YES in S1505), the main control unit 129 searches the non-network management session information storage unit 124 for the record 1240 in which the session ID registered in the field 1231 of the record 1230 is registered in the field 1244. .

  If such a record 1240 can be retrieved, there is a non-network management session that uses the network management session to be disconnected. In this case (YES in S1507), a network management external line deemed disconnection process described later is performed (S1508).

  On the other hand, when such a record 1240 cannot be retrieved, there is no network unmanaged session that uses the network management session to be disconnected. In this case (NO in S1507), the main control unit 129 transfers the BYE message to the call control server 2 via the SIP processing unit 125 and the network IF unit 121. After that, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121, via the call control server 2, to the IP telephone terminal 13 that is the transmission source of the BYE message and another local telephone system that is the transmission destination. The network management session established between the IP telephone terminal 13 belonging to the local call control server 12 and the other local call control server 12 is disconnected by relaying the SIP message exchanged with The network management external line disconnecting process is executed (S1509).

  Then, the main control unit 129 refers to the network management session information storage unit 123, registers the terminal ID of the BYE message transmission source in the field 1232, and stores the BYE message transmission destination telephone number in the fields 1233 and 1234. The record 1230 in which the IP address is registered is searched. Then, the searched record 1230 is deleted from the network management session information storage unit 123 (S1510).

  In step S1511, the main control unit 129 determines whether the BYE message is received via the unique message reception unit 127 or the SIP processing unit 125. When a BYE message is received via the unique message receiving unit 127 (“via the unique message receiving unit” in S1511), a second network management outside line disconnection process described later is performed (S1514).

  On the other hand, when the BYE message is received via the SIP processing unit 125 (“SIP processing unit” in S1511), the main control unit 129 refers to the network management session information storage unit 123 and sends the BYE message destination in the field 1232 And the record 1230 in which the telephone number and IP address of the other local telephone system 1 that is the transmission source of the BYE message are registered in the fields 1233 and 1234, and the field 1235 of the record 1230 is searched. (S1512).

  If the usage status is “use completed” (NO in S1512), network management external line disconnecting proxy processing described later is performed (S1513).

  On the other hand, when the usage status is “in use” (YES in S1512), the main control unit 129 transfers the BYE message to the destination of the BYE message via the SIP processing unit 125 and the network IF unit 121. After that, the main control unit 129 cooperates with the SIP processing unit 125 and the network IF unit 121 via the call control server 2 between the other private telephone system 1 that is the source of the BYE message and the destination of the BYE message. Network management that disconnects a network management session established between the IP telephone terminal 13 belonging to the local call control server 12 and another local call control server 12 by relaying SIP messages exchanged between them An outside line cutting process is performed (S1509).

  Then, the main control unit 129 deletes the record 1230 searched in S1512 from the network management session information storage unit 123 (S1510).

  FIG. 9 is a flowchart for explaining the first network management outside line disconnecting process (S1506) shown in FIG.

  First, the main control unit 129 searches the record 1240 from the non-network management session information storage unit 124 using the terminal ID of the BYE message transmission source as a key, and the usage target registered in the field 1244 of the record 1240 The session ID of the network management session is acquired. Next, using this session ID as a key, the record 1230 is further searched from the network management session information storage unit 123, and the usage status registered in the field 1235 of the searched record 1230 is confirmed (S150600).

  If the usage status of the network management session to be used is “in use” (YES in S150600), the process proceeds to S150602.

  On the other hand, when the usage status of the network management session to be used is “use completed” (NO in S150600), the main control unit 129 uses the record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Whether or not the record 1240 in which the terminal ID other than the terminal ID of the BYE message transmission source is registered in the field 1242 is registered in the non-network management session information storage unit 124, that is, this network management session is used. It is further checked whether there are other non-network management sessions (S150601). If there is another session outside the network management (YES in S150601), the process proceeds to S150602. On the other hand, if no other non-network management session exists (NO in step S150602), the process advances to step S150610.

  In step S150602, the main control unit 129 selects the relay terminal 13 from among the IP telephone terminals 13 belonging to the local call control server 12.

  Specifically, the usage status registered in the field 1235 of the record 1230 searched in S150600 (the record 1230 in which the session ID of the network management session to be used is registered in the field 1231) is confirmed. If “in use”, the IP telephone terminal 13 specified by the terminal ID registered in the field 1232 of this record 1230 is selected as the relay terminal 13.

  On the other hand, if the usage status is “use completed”, the record 1240 searched in S150601 (the record 1240 in which the session ID of the network management session to be used is registered in the field 1244, and the source of the BYE message Record 1240) in which terminal IDs other than the terminal ID are registered in the field 1242, one of the records 1240 is selected, and the IP specified by the terminal ID registered in the field 1242 of the record 1240 is selected. The telephone terminal 13 is selected as the relay terminal 13.

  Next, the main control unit 129 generates a unique message including a BYE message. In addition, the main control unit 129 refers to the terminal registration information storage unit 122 and identifies the IP address of the relay terminal 13. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S150603).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S150604).

  Next, when the main control unit 129 receives a 200 OK message from the destination of the BYE message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127 (YES in S150605), the main control unit 129 and the network This 200 OK message is transferred to the sender of the BYE message via the IF unit 121 (S150606).

  Next, the main control unit 129 retrieves the record 1240 from the non-network management session information storage unit 124 using the terminal ID of the BYE message transmission source as a key. Then, the searched record 1240 is deleted (S150607).

  Next, the main control unit 129 determines the quality of the voice data of the network management session to be used and the non-network management session using the network management session (S150608).

  Specifically, the number of non-network management sessions is measured by searching the network management session information storage unit 124 for a record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Also, the usage status registered in the field 1235 of the record 1230 (the record 1230 in which the session ID of the network management session to be used is registered in the field 1231) searched in S150600 is checked. If the usage status is “in use”, the larger the total number of network management sessions and non-network management sessions to be used, the lower the quality of voice data (for example, network management sessions and network management to be used). The quality of the audio data is set so that the compression rate increases in proportion to the total number of outside sessions. On the other hand, if the usage status is “end of use”, the larger the total number of non-network management sessions, the lower the quality of the voice data (for example, the compression rate is proportional to the total number of non-network management sessions to be used). Set the audio data quality to be higher).

  Next, the main control unit 129 refers to the network management session information storage unit 123 and sets the terminal ID registered in the field 1232 of the record 1230 in which the session ID of the network management session to be used is registered in the field 1231. Identify. Further, the non-network management session information storage unit 124 is referred to, and each terminal ID registered in the field 1242 of the record 1240 in which the session ID of the network management session to be used is registered in the field 1244 is specified. Then, the terminal registration information storage unit 122 is referred to, and the IP address of each IP telephone terminal 13 specified by these terminal IDs is specified. Then, the IP address is notified to the quality change request unit 128 together with the quality of the voice data determined in S150608.

  In response to this, the quality change request unit 128 transmits a change request to the determined quality of voice data to each of the IP telephone terminals 13 specified by these IP addresses via the network IF unit 121 ( S150609).

  In step S150610, the main control unit 129 transmits a BYE message for disconnecting the network management session to be used to the call control server 2 via the SIP processing unit 125 and the network IF unit 121.

  If the main control unit 129 receives a 200 OK message from the call control server 2 via the network IF unit 121 and the SIP processing unit 125 (YES in S150611), the main control unit 129 passes through the network IF unit 121 and the SIP processing unit 125. The 200 OK message corresponding to the BYE message is transmitted to the IP telephone terminal 13 that has transmitted the BYE message (S150612).

  Next, the main control unit 129 deletes the record 1230 in which the session ID of the network management session to be used is registered in the field 1231 from the network management session information storage unit 123 (S150613). Also, the record 1240 in which the terminal ID of the BYE message transmission source is registered in the field 1242 is deleted from the non-network management session information storage unit 124 (S150614).

  FIG. 10 is a flowchart for explaining the second network management outside line disconnecting process (S1514) shown in FIG.

  First, the main control unit 129 selects the relay terminal 13 from among the IP telephone terminals 13 belonging to the local call control server 12 (S151400). Specifically, the IP address of the IP telephone terminal 13 that is the transmission source of the unique message storing the BYE message is acquired from the unique message receiving unit 127. Then, this IP address is determined as the IP address of the relay terminal 13.

  Next, the main control unit 129 transmits the BYE message to the IP telephone terminal 13 designated as the BYE message transmission destination via the SIP processing unit 125 and the network IF unit 121 (S151040).

  Next, when receiving a 200 OK message from the BYE message transmission destination via the network IF unit 121 and the SIP processing unit 125 (YES in S151402), the main control unit 129 generates a unique message including the BYE message. Then, the main control unit 129 notifies this unique message together with the IP address of the relay terminal 13 to the unique message multiplexing request unit 126 (S151403).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S151404).

  Next, the main control unit 129 searches for the record 1240 from the non-network management session information storage unit 124 using the terminal ID of the destination of the BYE message as a key, and deletes this record 1240 (S151405).

  Next, the main control unit 129 determines the quality of the voice data of the network management session to be used and the non-network management session that uses this network management session (S151406).

  Specifically, the number of non-network management sessions is measured by searching the network management session information storage unit 124 for a record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Also, the record 1230 in which the session ID of the network management session to be used is registered in the field 1231 is searched from the network management session information storage unit 123, and the usage status registered in the field 1235 of the record 1230 is checked. If the usage status is “in use”, the larger the total number of network management sessions and non-network management sessions to be used, the lower the quality of voice data (for example, network management sessions and network management to be used). Set the compression ratio to be higher in proportion to the total number of outside sessions). On the other hand, if the usage status is “end of use”, the larger the total number of non-network management sessions, the lower the quality of voice data (for example, the compression rate increases in proportion to the total number of non-network management sessions). To).

  Next, the main control unit 129 refers to the network management session information storage unit 123 and sets the terminal ID registered in the field 1232 of the record 1230 in which the session ID of the network management session to be used is registered in the field 1231. Identify. Further, the non-network management session information storage unit 124 is referred to, and each terminal ID registered in the field 1242 of the record 1240 in which the session ID of the network management session to be used is registered in the field 1244 is specified. Then, by referring to the terminal registration information storage unit 122, the IP address of each IP telephone terminal 13 specified by these terminal IDs is specified, and these IP addresses are set together with the quality of the voice data determined in S151406. The change request unit 128 is notified.

  In response to this, the quality change request unit 128 transmits a change request to the determined quality of voice data to each of the IP telephone terminals 13 specified by these IP addresses via the network IF unit 121 ( S151407).

  FIG. 11 is a flowchart for explaining the network management external line deemed disconnection process (S1508) shown in FIG.

  First, the main control unit 129 selects the relay terminal 13 from among the IP telephone terminals 13 belonging to the local call control server 12 (S150800).

  Specifically, the network management session record 1230 to be used is retrieved from the network management session information storage unit 123 using the terminal ID of the BYE message transmission source as a key. Then, the session ID of the network management session to be used registered in the field 1231 of the record 1230 is specified. Next, the record 1240 in which the session ID is registered in the field 1244 is searched from the non-network management session information storage unit 124. Then, any one record 1240 is selected from the retrieved records 1240, and the IP telephone terminal 13 specified by the terminal ID registered in the field 1242 of this record 1240 is selected as the relay terminal 13.

  Next, the main control unit 129 generates a unique message including a BYE message. In addition, the main control unit 129 refers to the terminal registration information storage unit 122 and identifies the IP address of the relay terminal 13. Then, this unique message is notified to the unique message multiplexing request unit 126 together with the IP address of the relay terminal 13 (S150801).

  In response to this, the unique message multiplexing request unit 126 specifies the relay request for the unique message notified from the main control unit 129 by the IP address notified from the main control unit 129 together with the unique message. 13 through the network IF unit 121 (S150802).

  Next, when the main control unit 129 receives a 200 OK message from the destination of the BYE message via the relay terminal 13, the network IF unit 121, and the unique message receiving unit 127 (YES in S150803), the main control unit 129 receives the SIP processing unit 125 and the network. This 200 OK message is transferred to the source of the BYE message via the IF unit 121 (S150804).

  Next, the main control unit 129 retrieves the record 1230 from the network management session information storage unit 123 using the session ID of the network management session to be used as a key. Then, the usage status registered in the field 1235 of the searched record 1230 is changed from “in use” to “use completed” (S150805).

  Next, the main control unit 129 determines the quality of the voice data of each non-network management session that uses the target network management session (S150806).

  Specifically, by searching the record 1240 in which the session ID of the network management session to be used is registered in the field 1244 from the non-network management session information storage unit 124, the number of non-network management sessions is measured. The quality of the audio data is set so that the quality of the audio data becomes lower as the number increases (for example, the compression rate becomes higher in proportion to the total number of non-network management sessions).

  Next, the main control unit 129 refers to the non-network management session information storage unit 124, and registers the terminal ID registered in the field 1242 of the record 1240 in which the session ID of the network management session to be used is registered in the field 1244. Identify each one. Then, the IP address of each IP telephone terminal 13 specified by these terminal IDs is specified with reference to the terminal registration information storage unit 122. These IP addresses are notified to the quality change requesting unit 128 together with the quality of the audio data determined in S150806.

  In response to this, the quality change request unit 128 transmits a change request to the determined quality of voice data to each of the IP telephone terminals 13 specified by these IP addresses via the network IF unit 121 ( S150807).

  FIG. 12 is a flowchart for explaining the network management external line disconnecting proxy process (S1513) shown in FIG.

  First, the main control unit 129 searches for a non-network management session that uses a network management session to be disconnected, and identifies a connection terminal of the non-network management session (S151300). Specifically, the network management session record 1230 to be disconnected is searched from the network management session information storage unit 123 using the terminal ID of the BYE message transmission destination as a key. Then, the session ID of the network management session to be disconnected registered in the field 1231 of the record 1230 is specified. Next, the record 1240 in which the session ID is registered in the field 1244 is searched from the non-network management session information storage unit 124. Then, the main control unit 129 acquires the terminal ID registered in the field 1242 of the searched record 1240.

  Next, the main control unit 129 refers to the terminal registration information storage unit 122, and transmits a BYE message of the non-network management session to the IP telephone terminal 13 specified by the terminal ID (S151301).

  Next, if the main control unit 129 receives a 200 OK message from the BYE message transmission destination via the network IF unit 121 and the SIP processing unit 125 (YES in S151302), the main control unit 129 makes a network connection to the call control server 2. A 200 OK message for the BYE message of the management session is transmitted (S151030).

  Then, the main control unit 129 deletes the record 1230 of the network management session to be disconnected searched in S151300 from the network management session information storage unit 123 (S151304). Further, the record 1240 of the non-network management session using the network management session to be disconnected, searched in S151300, is deleted from the non-network management session information storage unit 124 (S151305).

  Next, the IP telephone terminal 13 will be described in detail.

  FIG. 13 is a schematic configuration diagram of the IP telephone terminal 13.

  As illustrated, the IP telephone terminal 13 includes a network IF unit 131, a SIP processing unit 132, an RTP processing unit 133, a multiplexing request receiving unit 134, a unique message transmitting unit 135, and a quality change request receiving unit 136. A voice data generating unit 137, a terminal ID adding unit 138, a unique message multiplexing unit 139, a voice data extracting unit 140, a unique message separating unit 141, a voice data reproducing unit 142, a speaker and a microphone. A handset 143, an operation panel 144 having various keys such as a numeric keypad, a display unit 145 such as an LCD, and a main control unit 146.

  The network IF unit 131 is an interface for connecting to the LAN 14 and the IP telephone network 3, and processes protocols (TCP, UDP, IP, Ethernet (registered trademark), etc.) of each layer below the transport layer.

  The SIP processing unit 132 processes the SIP message in accordance with an instruction from the main control unit 146.

  The RTP processing unit 133 processes an RTP (Realtime Transport Protocol) packet (voice packet) through a session established with the own IP telephone terminal 13.

  The multiplexing request receiving unit 134 receives a multiplexing request for a unique message from the local call control server 12 to which the own IP telephone terminal 13 belongs via the network IF unit 131.

  The unique message transmission unit 135 transmits a unique message to the local call control server 12 to which the own IP telephone terminal 13 belongs through the network IF unit 131 in accordance with an instruction from the main control unit 146.

  The quality change request receiving unit 136 receives a voice data quality change request from the local call control server 12 to which the own IP telephone terminal 13 belongs via the network IF unit 131.

  The audio data generation unit 137 encodes the audio signal input to the microphone of the handset 143 with the quality (compression rate) notified from the main control unit 146 to generate audio data.

  The terminal ID adding unit 138 adds the terminal ID of the own IP telephone terminal 13 to the voice data generated by the voice data generating unit 137. The terminal ID may be generated by combining an extension number and an IP address according to a predetermined rule.

  The unique message multiplexing unit 139 passes the voice data to which the terminal ID is added by the terminal ID adding unit 138 to the RTP processing unit 133. Here, if a unique message is notified from the main control unit 146, the unique message is multiplexed with the voice data to which the terminal ID is added, and then passed to the RTP processing unit 133.

  The voice data extraction unit 140 checks whether or not the terminal ID added to the voice data received from the RTP processing unit 133 is the terminal ID of the communication partner notified from the main control unit 146. If it is the terminal ID of the other party, the terminal ID is removed from the voice data, and the obtained voice data is passed to the unique message separation unit 141. On the other hand, if it is not the call partner's terminal ID, the voice data is discarded without being passed to the unique message separation unit 141.

  The unique message separation unit 141 passes the voice data received from the voice data extraction unit 140 to the voice data reproduction unit 142. Here, if a unique message is multiplexed with the voice data, the unique message is separated from the voice data and passed to the main control unit 146.

  The audio data reproduction unit 142 decodes and reproduces the audio data received from the unique message separation unit 141, and outputs the reproduction signal from the speaker of the handset 143.

  Then, the main control unit 146 comprehensively controls each unit 131 to 145 of the own IP telephone terminal 13.

  FIG. 14 is a flowchart for explaining the operation of the IP telephone terminal 13.

  First, the main control unit 146 transmits a REGISTER message to the local call control server 12 in the local telephone system 1 via the SIP processing unit 132 and the network IF unit 131, and sends the REGISTER message to the local call control server 12. Registration request processing is performed (S20). As a result, the own IP telephone terminal 13 belongs to the local call control server 12.

  Next, when the main control unit 146 receives a call instruction from the user via the operation panel 144 (YES in S21), the main IP telephone terminal 13 belongs via the SIP processing unit 132 and the network IF unit 131. An INVITE message is transmitted to the call control server 12 with the telephone number designated by the user as the transmission destination number. The main control unit 146 cooperates with the SIP processing unit 132 and the network IF unit 131 to perform call processing by exchanging SIP messages with the local call control server 12 (S22). Further, the main control unit 146 exchanges the terminal ID with the call partner through the exchange of the SIP message (S23). For example, the terminal ID of the own IP telephone terminal 13 is inserted into the INVITE message, and the terminal ID of the IP telephone terminal 13 of the other party is acquired from the 200 OK message.

  Then, the main control unit 146 controls each unit 131 to 145 of the own IP telephone terminal 13 and starts a call process to be described later (S27).

  When the main control unit 146 receives the INVITE message from the local call control server 12 to which the own IP telephone terminal 13 belongs via the SIP processing unit 132 and the network IF unit 131 (YES in S24), it returns a 180 Ringing message. To do. Then, the main control unit 146 cooperates with the SIP processing unit 132 and the network IF unit 131 to perform incoming processing by exchanging SIP messages with the local call control server 12 (S25). Further, the main control unit 146 exchanges the terminal ID with the other party through the exchange of the SIP message (S26). For example, the terminal ID of the other party's IP telephone terminal 13 is acquired from the INVITE message, and the terminal ID of the own IP telephone terminal 13 is inserted into the 200 OK message.

  Then, the main control unit 146 controls each unit 131 to 145 of the own IP telephone terminal 13 and starts a call process to be described later (S27).

  After the call processing is started as described above, when the main control unit 146 receives a disconnection instruction from the user via the operation panel 144 (YES in S28), the main control unit 146 causes the SIP processing unit 132 and the network IF unit 131 to operate. Then, a disconnection process is performed by transmitting a BYE message to the local call control server 12 to which the own IP telephone terminal 13 belongs (S29). As a result, the main control unit 146 ends the call processing described later (S32).

  Further, when the main control unit 146 receives the BYE message from the local call control server 12 to which the IP telephone terminal 13 belongs via the SIP processing unit 132 and the network IF unit 131 (YES in S30), the main control unit 146 returns a 200 OK message. Thus, the cutting process is performed (S31). As a result, the main control unit 146 ends the call processing described later (S32).

  FIG. 15 is a flowchart for explaining the call processing of the IP telephone terminal 13.

  First, when the main control unit 146 receives a change request from the local call control server 12 to which the own IP telephone terminal 13 belongs via the network IF unit 131 and the quality change request receiving unit 136 (YES in S2701), this change is performed. The quality (compression rate) specified in the request is set in the audio data generation unit 137 (S2702). Thereby, the audio data generation unit 137 encodes the audio signal input to the microphone of the handset 143 with the quality notified from the main control unit 146, and generates audio data.

  When the main control unit 146 receives a multiplexing request for a unique message from the local call control server 12 to which the IP telephone terminal 13 belongs via the network IF unit 131 and the multiplexing request receiving unit 134 (YES in S2703). The unique message is set in the unique message multiplexing unit 139 as a multiplexing target (S2704).

  Also, the voice data generation unit 137 delivers the voice data generated after the previous voice packet transmission timing to the terminal ID addition unit 138 when the voice packet transmission timing arrives regularly (YES in S2705) (S2706). In response to this, the terminal ID adding unit 138 adds the terminal ID of the own IP telephone terminal 13 to the voice data received from the voice data generating unit 137, and converts the voice data with the terminal ID into the unique message multiplexing unit 139. (S2707).

  In response, if the unique message is set as a multiplexing target (YES in S2708), the unique message multiplexing unit 139 multiplexes the unique message to be multiplexed into the voice data with the terminal ID. The obtained data is transferred to the RTP processing unit 133 (S2709). In response to this, the RTP processing unit 133 stores the voice data with the terminal ID multiplexed with the unique message in the voice packet, and transmits the voice packet to the other party in the session via the network IF unit 131. (S2710).

  On the other hand, when the unique message is not set to be multiplexed (NO in S2708), the unique message multiplexing unit 139 immediately passes the voice data to which the terminal ID is added to the RTP processing unit 133. Receiving this, the RTP processing unit 133 stores the voice data with the terminal ID in the voice packet, and transmits the voice packet to the call partner via the network IF unit 131 (S2710).

  Further, when the RTP processing unit 133 receives the RTP packet multicast-distributed by the gateway 11 via the network IF unit 131 (YES in S2711), the RTP processing unit 133 extracts the audio data from the RTP packet and converts the audio data into the audio data. It passes to the extraction unit 140. The voice data extracting unit 140 checks whether or not the terminal ID added to the voice data is the terminal ID of the communication partner notified from the main control unit 146 (S2712). If the additional terminal ID of the voice data is not the call partner's terminal ID (NO in S2712), the voice data is discarded without being passed to the unique message separation unit 141 (S2716). On the other hand, if the additional terminal ID of the voice data is the terminal ID of the other party (YES in S2712), the terminal ID added to the voice data is removed, and the obtained voice data is converted into the unique message separation unit 141. To pass.

  In response to this, the unique message separation unit 141 checks whether or not the unique message is multiplexed with the voice data received from the voice data extraction unit 140 (S2713).

  If the unique message is multiplexed (YES in S2713), the unique message separation unit 141 separates this unique message from the voice data and passes it to the main control unit 146. The main control unit 146 transmits this unique message to the local call control server 12 to which the own IP telephone terminal 13 belongs via the unique message transmission unit 135 and the network IF unit 131 (S2714). Further, the unique message separation unit 141 passes the voice data from which the unique message is separated to the voice data reproduction unit 142.

  On the other hand, when the unique message is not multiplexed (NO in S2713), the unique message separation unit 141 immediately passes the audio data received from the audio data extraction unit 140 to the audio data reproduction unit 142.

  The audio data reproduction unit 142 reproduces the audio data received from the unique message separation unit 141 and outputs the reproduction signal from the speaker of the handset 143 (S2715).

  Next, an operation example of the IP telephone system shown in FIG. 1 will be described.

  First, an operation example when a non-network management session is established will be described.

  FIGS. 16 and 17 are sequence diagrams for explaining an operation example of the IP telephone system when a non-network management session is established.

  Here, the local telephone system [A] 1 has established network management sessions for the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3, one of which is the local telephone system [B] 1. (S301).

  When the IP telephone terminal [A01] 13 in the local telephone system [A] 1 receives a call instruction from the user to the local telephone system [B] 1, the local call to which the IP telephone terminal [A01] 13 belongs is assigned. An INVITE message with the local telephone system [B] 1 as the transmission destination is transmitted to the control server [A] 12 (S302).

  In response to this, the local call control server [A] 12 generates a unique message including this INVITE message and uses this local telephone to establish a network management session with the local telephone system [B] 1. It is transmitted to the IP telephone terminal [A02] 13 in the system [A] 1 (S303). The local call control server [A] 12 returns a 100 Trying message to the IP telephone terminal [A01] 13 (S304).

  The IP telephone terminal [A02] 13 multiplexes the original message received from the local call control server [A] 12 into the voice data to which the terminal ID of the own IP telephone terminal [A02] 13 is attached. Store in and send. This voice packet reaches the gateway [B] 11 of the local telephone system [B] 1 via the gateway [A] 11 of the local telephone system [A] 1 and the IP telephone network 3. The gateway [B] 11 transmits the voice packet to the private telephone system [B] 1 by multicast. The IP telephone terminal [B02] 13 in the private telephone system [B] 1 that is the other party of the IP telephone terminal [A02] 13 receives the IP telephone terminal [A02] that is the other party from the voice packet transmitted by multicast. ] The voice data addressed to itself to which the terminal ID of 13 is assigned is acquired. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [B02] 13 via the network management session (S305).

  The IP telephone terminal [B02] 13 separates the unique message multiplexed in the voice data addressed to itself, and the private message is assigned to the local call control server [B] to which the own IP telephone terminal [B02] 13 belongs. 12 (S306).

  In response to this, the local call control server [B] 12 transmits the INVITE message stored in this unique message to each IP telephone terminal 13 belonging to the local call control server [B] 12 (S307). . Further, the local call control server [B] 12 returns a unique message storing the 100 Trying message to the IP telephone terminal [B02] 13 (S308).

  The IP telephone terminal [B02] 13 multiplexes the unique message received from the local call control server [B] 12 into voice data to which the terminal ID of the own IP telephone terminal [B02] 13 is attached, Store in and send. This voice packet reaches the gateway [A] 11 via the gateway [B] 11 and the IP telephone network 3. Then, the gateway [A] 11 transmits this voice packet to the private telephone system [A] 1 by multicast. The IP telephone terminal [A02] 13, which is the other party of the IP telephone terminal [B02] 13, is given the terminal ID of the IP telephone terminal [B02] 13, which is the other party, from the voice packet transmitted by multicast. Acquires audio data addressed to itself. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [A02] 13 via the network management session (S309). The IP telephone terminal [A02] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [A] 12. Thereby, the local call control server [A] 12 receives the 100 Trying message (S310).

  When the private call control server [B] 12 receives 180 Ringing from each IP telephone terminal 13 belonging to the private private call control server [B] 12 (S311), the private call control server [B] 12 sends an original message storing the 180 Ringing message to the IP telephone terminal. [B02] 13 is returned (S312).

  The IP telephone terminal [B02] 13 multiplexes the unique message received from the local call control server [B] 12 into voice data to which the terminal ID of the own IP telephone terminal [B02] 13 is attached, Store in and send. This voice packet reaches the gateway [A] 11 via the gateway [B] 11 and the IP telephone network 3. Then, the gateway [A] 11 transmits this voice packet to the private telephone system [A] 1 by multicast. The IP telephone terminal [A02] 13, which is the other party of the IP telephone terminal [B02] 13, is given the terminal ID of the IP telephone terminal [B02] 13, which is the other party, from the voice packet transmitted by multicast. Acquires audio data addressed to itself. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [A02] 13 via the network management session (S313).

  The IP telephone terminal [A02] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [A] 12 (S314). In response, the local call control server [A] 12 transmits the 180 Ringing message stored in this unique message to the IP telephone terminal [A01] 13 (S315).

  In the local telephone system [B] 1, when receiving a response instruction from the user, the IP telephone terminal [B01] 13 transmits a 200 OK message to the local call control server [B] 12 (S316). The local call control server [B] 12 transmits a unique message storing this 200 OK message to the IP telephone terminal [B02] 13 (S317).

  The IP telephone terminal [B02] 13 multiplexes the unique message received from the local call control server [B] 12 into voice data to which the terminal ID of the own IP telephone terminal [B02] 13 is attached, Store in and send. This voice packet reaches the gateway [A] 11 via the gateway [B] 11 and the IP telephone network 3. Then, the gateway [A] 11 transmits this voice packet to the private telephone system [A] 1 by multicast. The IP telephone terminal [A02] 13, which is the other party of the IP telephone terminal [B02] 13, is given the terminal ID of the IP telephone terminal [B02] 13, which is the other party, from the voice packet transmitted by multicast. Acquires audio data addressed to itself. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [A02] 13 via the network management session (S318).

  The IP telephone terminal [A02] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [A] 12 (S319). In response, the local call control server [A] 12 transmits the 200 OK message stored in this unique message to the IP telephone terminal [A01] 13 (S320).

  Upon receiving the 200 OK message from the local call control server [A] 12, the IP telephone terminal [A01] 13 returns an ACK message (S321). In response to this, the local call control server [A] 12 generates a unique message including this ACK message and transmits it to the IP telephone terminal [A02] 13 (S322).

  The IP telephone terminal [A02] 13 multiplexes the original message received from the local call control server [A] 12 into the voice data to which the terminal ID of the own IP telephone terminal [A02] 13 is attached. Store in and send. This voice packet reaches the gateway [B] 11 via the gateway [A] 11 and the IP telephone network 3. The gateway [B] 11 transmits the voice packet to the private telephone system [B] 1 by multicast. The IP telephone terminal [B02] 13 in the private telephone system [B] 1, which is the other party of the IP telephone terminal [A02] 13, transmits the IP telephone terminal [A02] that is the other party of the telephone call from the voice packet transmitted by multicast. The voice data addressed to itself to which the terminal ID of 13 is assigned is acquired. Thus, the unique message multiplexed in the voice data is notified to the IP telephone terminal [B02] 13 through the network management session (S323).

  The IP telephone terminal [B02] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [B] 12 (S324). The local call control server [B] 12 transmits this ACK message to the IP telephone terminal [B01] 13 (S325).

  Thereafter, the local call control server [A] 12 notifies each of the IP telephone terminal [A01] 13 and the IP telephone terminal [A02] 13 of a voice data quality change request (S326). Similarly, the local call control server [B] 12 notifies the IP telephone terminal [B01] 13 and the IP telephone terminal [B02] 13 of a request for changing the quality of the voice data (S327).

  Thus, a non-network management session is established through the network management session between the local telephone system [A] 1 and the local telephone system [B] 1 (S328). Thereby, a call between the IP phone terminal [A02] 13 and the IP phone terminal [B02] 13 and a call between the IP phone terminal [A01] 13 and the IP phone terminal [B01] 13 can be performed simultaneously.

  Next, an operation example when the non-network management session is disconnected will be described.

  FIG. 18 is a sequence diagram for explaining an operation example of the IP telephone system when a session outside the network management is disconnected.

  Here, a network management session is established between the IP telephone terminal [A02] 13 in the private telephone system [A] 1 and the IP telephone terminal [B02] 13 in the private telephone system [B] 1, and the private telephone system A non-network management session using this network management session is established between the IP telephone terminal [A01] 13 in [A] 1 and the IP telephone terminal [B01] 13 in the private telephone system [B] 1. (S400).

  When the IP telephone terminal [A01] 13 receives a disconnection instruction from the user, the IP telephone terminal [B01] 13 is transmitted to the local call control server [A] 12 to which the IP telephone terminal [A01] 13 belongs. A BYE message is transmitted (S401).

  In response, the local call control server [A] 12 generates a unique message including this BYE message and establishes a network management session with the local telephone system [B] 1 using this IP telephone terminal. [A02] 13 (S402).

  The IP telephone terminal [A02] 13 multiplexes the original message received from the local call control server [A] 12 into the voice data to which the terminal ID of the own IP telephone terminal [A02] 13 is attached. Store in and send. This voice packet reaches the gateway [B] 11 of the local telephone system [B] 1 via the gateway [A] 11 of the local telephone system [A] 1 and the IP telephone network 3. The gateway [B] 11 transmits the voice packet to the private telephone system [B] 1 by multicast. The IP telephone terminal [B02] 13 in the private telephone system [B] 1 that is the other party of the IP telephone terminal [A02] 13 receives the IP telephone terminal [A02] that is the other party from the voice packet transmitted by multicast. ] The voice data addressed to itself to which the terminal ID of 13 is assigned is acquired. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [B02] 13 via the network management session (S403).

  The IP telephone terminal [B02] 13 separates the unique message multiplexed in the voice data addressed to itself, and the private message is assigned to the local call control server [B] to which the own IP telephone terminal [B02] 13 belongs. 12 (S404).

  In response to this, the local call control server [B] 12 transmits the BYE message stored in this unique message to the IP telephone terminal [B01] 13 (S405). In response to this, the IP telephone terminal [B01] 13 returns a 200 OK message to the local call control server [B] 12 (S406). The local call control server [B] 12 transmits a unique message storing the 200 OK message to the IP telephone terminal [B02] 13 (S407).

  The IP telephone terminal [B02] 13 multiplexes the unique message received from the local call control server [B] 12 into voice data to which the terminal ID of the own IP telephone terminal [B02] 13 is attached, Store in and send. This voice packet reaches the gateway [A] 11 via the gateway [B] 11 and the IP telephone network 3. Then, the gateway [A] 11 transmits this voice packet to the private telephone system [A] 1 by multicast. The IP telephone terminal [A02] 13 that is the other party of the IP telephone terminal [B02] 13 is assigned the terminal ID of the IP telephone terminal [B02] 13 that is the other party from the voice packet transmitted by multicast. Get the audio data for the address. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [A02] 13 via the network management session (S408).

  The IP telephone terminal [A02] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [A] 12 (S409). In response to this, the local call control server [A] 12 transmits the 200 OK message stored in this unique message to the IP telephone terminal [A01] 13 (S410).

  Thereafter, the local call control server [A] 12 notifies the IP telephone terminal [A02] 13 of a request for changing the quality of the voice data (S411). Similarly, the local call control server [B] 12 notifies the IP telephone terminal [B02] 13 of a voice data quality change request (S412).

  As described above, the non-network management session established between the IP telephone terminal [A01] 13 and the IP telephone terminal [B01] 13 is disconnected (S413).

  FIG. 19 is a sequence diagram for explaining an operation example of the IP telephone system when a network management session is deemed disconnected.

  Here, a network management session is established between the IP telephone terminal [A02] 13 in the private telephone system [A] 1 and the IP telephone terminal [B02] 13 in the private telephone system [B] 1, and the private telephone system A non-network management session using this network management session is established between the IP telephone terminal [A01] 13 in [A] 1 and the IP telephone terminal [B01] 13 in the private telephone system [B] 1. (S500).

  When the IP telephone terminal [A02] 13 receives a disconnection instruction from the user, the IP telephone terminal [B02] 13 is transmitted to the local call control server [A] 12 to which the IP telephone terminal [A02] 13 belongs. A BYE message is transmitted (S501).

  In response to this, the local call control server [A] 12 generates a unique message including this BYE message, and establishes a non-network management session with the local telephone system [B] 1. This is transmitted to the telephone terminal [A01] 13 (S502).

  The IP telephone terminal [A01] 13 multiplexes the unique message received from the local call control server [A] 12 into voice data to which the terminal ID of the own IP telephone terminal [A01] 13 is attached, and this is multiplexed into a voice packet. Store and send. This voice packet reaches the gateway [B] 11 of the local telephone system [B] 1 via the gateway [A] 11 of the local telephone system [A] 1 and the IP telephone network 3. The gateway [B] 11 transmits the voice packet to the private telephone system [B] 1 by multicast. The IP telephone terminal [B01] 13 that is the other party of the IP telephone terminal [A01] 13 is assigned the terminal ID of the IP telephone terminal [A01] 13 that is the other party from the voice packet transmitted by multicast. Get the audio data for the address. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [B01] 13 via the non-network management session using the network management session (S503).

  The IP telephone terminal [B01] 13 separates the unique message multiplexed in the voice data addressed to itself, and the private message is assigned to the local call control server [B] to which the own IP telephone terminal [B01] 13 belongs. 12 is transmitted (S504).

  In response to this, the local call control server [B] 12 transmits the BYE message stored in this unique message to the IP telephone terminal [B02] 13 (S505). In response to this, the IP telephone terminal [B02] 13 returns a 200 OK message to the local call control server [B] 12 (S506). The local call control server [B] 12 transmits a unique message storing this 200 OK message to the IP telephone terminal [B01] 13 (S507).

  The IP telephone terminal [B01] 13 multiplexes the unique message received from the local call control server [B] 12 into voice data to which the terminal ID of the own IP telephone terminal [B01] 13 is attached, and this is multiplexed into a voice packet. Store and send. This voice packet reaches the gateway [A] 11 via the gateway [B] 11 and the IP telephone network 3. Then, the gateway [A] 11 transmits this voice packet to the private telephone system [A] 1 by multicast. The IP telephone terminal [A01] 13, which is the other party of the IP telephone terminal [B01] 13, is given the terminal ID of the IP telephone terminal [B01] 13, which is the other party, from the voice packet transmitted by multicast. Acquires audio data addressed to itself. As a result, the unique message multiplexed in the voice data is notified to the IP telephone terminal [A01] 13 via the non-network management session using the network management session (S508).

  The IP telephone terminal [A01] 13 separates the unique message multiplexed in the voice data addressed to itself and transmits this unique message to the local call control server [A] 12 (S509). In response to this, the local call control server [A] 12 transmits the 200 OK message stored in this unique message to the IP telephone terminal [A02] 13 (S510).

  Thereafter, the local call control server [A] 12 notifies the IP telephone terminal [A01] 13 of a voice data quality change request (S511). Similarly, the local call control server [B] 12 notifies the IP telephone terminal [B01] 13 of a voice data quality change request (S512).

  Thus, the call between the IP telephone terminal [A01] 13 and the IP telephone terminal [B01] 13 is terminated, but the network management session is still established on the IP telephone network 3, and the IP telephone terminal [A02] 13 and The non-network management session between the IP telephone terminals [B02] 13 is maintained using this network management session (S513).

  FIG. 20 is a sequence diagram for explaining an operation example of the IP telephone system in the case where the network management session is disconnected when the non-network management session is disconnected.

  Here, a network management session is established between the IP telephone terminal [A02] 13 in the private telephone system [A] 1 and the IP telephone terminal [B02] 13 in the private telephone system [B] 1, and the private telephone system [A] An out-of-network management session using this network management session is established between the IP telephone terminal [A01] 13 in 1 and the IP telephone terminal [B01] 13 in the private telephone system [B] 1 Thereafter, it is assumed that the call between the IP phone terminal [A02] 13 and the IP phone terminal [B02] 13 is terminated (S600).

  When the IP telephone terminal [A01] 13 receives a disconnection instruction from the user, the IP telephone terminal [B01] 13 is transmitted to the local call control server [A] 12 to which the IP telephone terminal [A01] 13 belongs. A BYE message is transmitted (S601).

  In response, the local call control server [A] 12 disconnects the network management session established for the call between the IP telephone terminal [A02] 13 and the IP telephone terminal [B02] 13. A BYE message for this network management session is transmitted to the IP telephone network 3 via the gateway [A] 11. This BYE message reaches the private call control server [B] 12 via the gateway [B] 11 via the call control server 2 (not shown in FIG. 20) (S602).

  When the local call control server [B] 12 receives the BYE message for the network management session from the local call control server [A] 12 via the call control server 2, the IP telephone terminal [A02] 13 and the IP telephone terminal [B02] Since the communication with the network 13 has already ended, a BYE message is transmitted to the IP telephone terminal [B01] 13 in order to disconnect the non-network management session that uses this network management session (S603). In response to this, the IP telephone terminal [B01] 13 returns a 200 OK message to the local call control server [B] 12 (S604). The local call control server [B] 12 transmits a 200 OK message corresponding to the BYE message received from the local call control server [A] 12 via the call control server 2 to the IP telephone network 3 via the gateway [B] 11. The 200 OK message reaches the local call control server [A] 12 via the gateway [A] 11 via the call control server 2 (S605).

  When the local call control server [A] 12 receives the 200 OK message from the local call control server [B] 12 via the call control server 2, the IP telephone terminal [A01] 13 A 200 OK message corresponding to the BYE message received from is transmitted (S606).

  As described above, the non-network management session established between the IP telephone terminal [A01] 13 and the IP telephone terminal [B01] 13 is disconnected together with the network management session used by the non-network management session.

  The embodiment of the present invention has been described above.

  In the present embodiment, the local call control server 12 of each local telephone system 1 belongs to the local telephone control server 12 among the local telephone systems 1 connected to each other via the IP telephone network 3. In cooperation with the IP telephone terminal 13 in the system 1, a unique message storing SIP messages is exchanged using a network management session established with the local telephone system 1 on the other party side. Thereby, one or more non-network management sessions are established in the network management session.

  Therefore, it is possible to simultaneously establish a session with the number of contracted lines or more with the IP telephone service provider that provides the IP telephone network 3.

  In this embodiment, the local call control server 12 has the number of network management sessions reaching the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3, and the local telephone system on the other party side When a network management session is established with the network management session 1, the network management session is used to establish a non-network management session.

  Therefore, according to the present embodiment, the network management session can be preferentially used.

  In this embodiment, the local call control server 12 has the number of network management sessions reaching the number of contracted lines with the IP telephone service provider that provides the IP telephone network 3, and the local telephone system on the other party side When a network management session is not established with the local telephone system 1, the BUSY message is transmitted to the IP telephone terminal 13 in the local telephone system 1 that has transmitted the INVITE message, and busy processing is performed.

  Therefore, according to the present embodiment, it is possible to prevent an increase in traffic of the IP telephone network 3 due to exchange of meaningless SIP messages that are unlikely to establish a session.

  Further, in this embodiment, when the local call control server 12 receives a BYE message from the IP telephone terminal 13 connected to the network management session, if there is a non-network management session using this network management session, By exchanging SIP messages using this non-network management session, the call between the IP telephone terminals 13 connected to this network management session is terminated while maintaining this network management session.

  Therefore, according to the present embodiment, it is possible to maintain a non-network management session using this network management session even after the call between the IP telephone terminals 13 connected to this network management session is terminated.

  In the present embodiment, when the local call control server 12 receives a BYE message from the IP telephone terminal 13 connected to the non-network management session, the local call control server 12 is connected to the network management session using the non-network management session. When the call between the telephone terminals 13 is terminated and there is no other network management session using this network management session, a BYE message of this network management session is transmitted to the IP telephone network 3 The network management session is disconnected together with the non-network management session.

  Therefore, according to the present embodiment, it is possible to prevent an unused network management session from remaining indefinitely.

  In the present embodiment, the local call control server 12 uses each network management session and each IP telephone terminal connected to the network management session and the non-network management session when the non-network management session is established. 13 is notified of a change request to the quality (compression rate) corresponding to the number of non-network management sessions. Then, the IP telephone terminal 13 generates and transmits voice data with the quality notified from the local call control server 12.

  Therefore, according to the present embodiment, even when a plurality of non-network management sessions are established using a network management session, each IP telephone terminal 13 connected to the network management session and the non-network management session is more It becomes possible to make a call with the other party without fail.

  In addition, this invention is not limited to said embodiment, Many deformation | transformation are possible within the range of the summary.

  For example, in the above embodiment, the local call control server 12 creates the unique message by storing the SIP message in the payload, but the present invention is not limited to this. Call control messages may be defined independently. Then, conversion from a SIP message to a unique call control message and conversion from a unique call control message to a SIP message may be performed using a conversion table or the like.

  In the above embodiment, the configuration of the local call control server 12 and the IP telephone terminal 13 shown in FIGS. 2 and 13 is an integrated logic such as ASIC (Application Specific Integrated Circuit) or FPGA (Field Programmable Gate Array). It may be executed in hardware by an IC, or may be executed in software by a computer such as a DSP (Digital Signal Processor). Alternatively, in a general-purpose computer such as a PC (Personal Computer) equipped with an auxiliary storage device such as a CPU, memory, HDD, DVD-ROM, and a communication interface such as a NIC (Network Interface Card) and a modem, the CPU executes a predetermined program. It may be realized by loading from an auxiliary storage device onto a memory and executing it.

FIG. 1 is a schematic diagram of an IP telephone system according to an embodiment of the present invention. FIG. 2 is a schematic configuration diagram of the local call control server 12. 3A is a diagram schematically showing an example of registered contents in the network management session information storage unit 123. FIG. 3B is a schematic example of registered contents in the non-network management session information storage unit 124. FIG. FIG. 4 is a flowchart for explaining the operation of the local call control server 12. FIG. 5 is a flowchart for explaining the outgoing / incoming call processing (S13) shown in FIG. FIG. 6 is a flowchart for explaining the network management outside line transmission processing (S1309) shown in FIG. FIG. 7 is a flowchart for explaining the network management outside line incoming call processing (S1314) shown in FIG. FIG. 8 is a flowchart for explaining the cutting process (S15) shown in FIG. FIG. 9 is a flowchart for explaining the first network management outside line disconnecting process (S1506) shown in FIG. FIG. 10 is a flowchart for explaining the second network management outside line disconnecting process (S1514) shown in FIG. FIG. 11 is a flowchart for explaining the network management external line deemed disconnection process (S1508) shown in FIG. FIG. 12 is a flowchart for explaining the network management external line disconnecting proxy process (S1513) shown in FIG. FIG. 13 is a schematic configuration diagram of the IP telephone terminal 13. FIG. 14 is a flowchart for explaining the operation of the IP telephone terminal 13. FIG. 15 is a flowchart for explaining the call processing of the IP telephone terminal 13. FIG. 16 is a sequence diagram for explaining an operation example of the IP telephone system in a case where a non-network management session is established. FIG. 17 is a sequence diagram for explaining an example of the operation of the IP telephone system when a non-network management session is established. FIG. 18 is a sequence diagram for explaining an operation example of the IP telephone system when a session outside the network management is disconnected. FIG. 19 is a sequence diagram for explaining an operation example of the IP telephone system when a network management session is deemed disconnected. FIG. 20 is a sequence diagram for explaining an operation example of the IP telephone system in the case where the network management session is disconnected when the non-network management session is disconnected.

Explanation of symbols

  1: local telephone system, 2: call control server, 3: IP telephone network, 11: gateway, 12: local call control server, 13: IP telephone terminal, 14: LAN, 121: network IF unit, 122: terminal registration information Storage unit 123: Network management session information storage unit 124: Non-network management session information storage unit 125: SIP processing unit 126: Unique message multiplexing request unit 127: Unique message reception unit 128: Quality change request unit 129: Main control unit 131: Network IF unit 132: SIP processing unit 133: RTP processing unit 134: Multiplexing request receiving unit 135: Unique message transmitting unit 136: Quality change request receiving unit 137: Audio data generation unit, 138: terminal ID addition unit, 139: unique message multiplexing unit, 140: audio data extraction unit, 141: Own message extracting unit, 142: voice data reproducing unit, 143: a handset, 144: operation panel, 145: display unit, 146: main control unit

Claims (9)

An IP telephone system having a plurality of local telephone systems connected to each other via an IP telephone network,
The local telephone system is
A local call control server;
A plurality of IP telephone terminals accommodated in the local call control server;
A gateway for connecting a local telephone system to the IP telephone network,
The local call control server is:
A multiplexing request including call control information received from any of the IP telephone terminals is sent to another IP telephone terminal that is establishing a session with another local telephone system including the destination of the call control information. Call control information multiplexing request means for transmitting;
Call control information notifying means for notifying the call control information received from any of the IP telephone terminals to the other IP telephone terminal that is the destination of the call control information,
The IP telephone terminal
Call control information multiplexing means for multiplexing the call control information included in the multiplexing request received from the local call control server into the payload of a voice packet to be transmitted through the session being established;
Terminal information multiplexing means for multiplexing terminal information, which is identification information of the own IP telephone terminal, in a payload of a voice packet transmitted through the session being established;
Call control information separating means for separating call control information multiplexed in a payload of a voice packet received via the session being established, and transmitting the call control information to the local call control server;
Terminal information separating means for separating terminal information multiplexed in the payload of a voice packet received via the session being established;
Voice reproduction means for reproducing voice data stored in a payload of the voice packet when the terminal information separated by the terminal information separation means is terminal information of a communication partner of the own IP telephone terminal; ,
The gateway is
Multicast changing means for changing the destination address of a voice packet received from another local telephone system via the IP telephone network to a multicast address and transmitting the multicast packet to the local telephone system to which the gateway belongs. IP phone system. The IP telephone system according to claim 1,
The local call control server is:
Session monitoring means for monitoring a network management session managed by the IP telephone network, which is a session connected to the IP telephone terminal,
The call control information multiplexing request means includes:
When there is a predetermined number of the network management sessions, and any one of the network management sessions is established with another local telephone system including a destination of call control information received from the IP telephone terminal, An IP telephone system, wherein a multiplexing request including the call control information is transmitted to the other IP telephone terminal connected to the network management session. The IP telephone system according to claim 2,
The local call control server is:
When the network management session is the predetermined number, and any of the network management sessions is not established with another local telephone system including a destination of call control information received from the IP telephone terminal, An IP telephone system further comprising busy processing means for performing busy processing on the IP telephone terminal. The IP telephone system according to claim 2 or 3,
The session monitoring means includes
For each network management session, a session established by using the network management session by the call control information multiplexing requesting means and the call control information notifying means and not managed by the IP telephone network Monitor sessions,
The call control information multiplexing request means includes:
When call control information for a disconnection request is received from the IP telephone terminal connected to the network management session, if there is a session outside the network management that uses the network management session, the connection to the session other than the network management session A multiplexing request including call control information for the disconnection request is transmitted to the IP telephone terminal. The IP telephone system according to claim 4, wherein
The local call control server is:
When call control information for a disconnection request is received from the IP telephone terminal connected to the non-network management session, the other IP telephone terminal connected to the network management session used by the non-network management session and the other party If the call control information of the disconnection request has been transmitted and received and there is no other non-network management session using the network management session, the call control information of the disconnection request for the network management session is sent to the IP telephone network. An IP telephone system, further comprising a network management session disconnection request means for transmitting. The IP telephone system according to claim 4 or 5,
The local call control server is:
Quality change notification means for notifying the IP telephone terminal connected to each of the network management session and the non-network management session that uses the network management session of a change request to a quality corresponding to the number of non-network management sessions Further comprising
The IP telephone terminal
Voice coding means for coding voice data to be stored in a payload of a voice packet to be transmitted through an established session according to the quality specified in the change request received from the local call control server. IP phone system.   The local call control server according to any one of claims 1 to 6.   The IP telephone terminal according to any one of claims 1 to 6. Between a private telephone system having a private call control server, a plurality of IP telephone terminals accommodated in the private call control server, and a gateway for connecting the private call control server and the IP telephone terminal to an IP telephone network A communication method in which
The local call control server is
A multiplexing request including call control information received from any of the IP telephone terminals is sent to another IP telephone terminal that is establishing a session with another local telephone system including the destination of the call control information. Sending the call control information received from any of the IP telephone terminals to the other IP telephone terminal that is the destination of the call control information,
The IP telephone terminal is
The call control information included in the multiplexing request received from the local call control server and the terminal information which is the identification information of the own IP telephone terminal are multiplexed on the payload of the voice packet transmitted through the session being established. And
The call control information and terminal information multiplexed in the payload of the voice packet received through the session are separated, and the call control information is transmitted to the local call control server. When it is terminal information of the communication partner of the terminal, the voice data stored in the payload of the voice packet is decoded,
The gateway is
A communication method, wherein a destination address of a voice packet received from another local telephone system via the IP telephone network is changed to a multicast address and transmitted to the local telephone system to which the gateway belongs.

Images