JP5387898B2 - COMMUNICATION TERMINAL, CALL CONTROL DEVICE, AND COMMUNICATION PROGRAM - Google Patents

Description

  The present invention relates to a communication terminal, a call control device, and a communication program.

  In the case of Internet communication performed using a communication protocol such as HTTP (Hypertext Transfer Protocol), if there is no content providing site, it is notified that the server could not be found. That is, it is notified that it is in an error status.

  In this case, the operator checks the spelling of the designated address and accesses other content providing sites.

  The conventional technique disclosed in Patent Document 1 can avoid a situation in which facsimile communication is left unsuccessful even when an attempt is made to perform facsimile communication by setting a destination with a high error frequency. The technology that has been made public.

  In Patent Document 1, a communication history for a destination in facsimile communication is recorded, an error occurrence frequency related to the destination is determined based on the communication history, and the result is displayed on a display screen.

JP 2009-005295 A

  It is an object of the present invention to provide a communication terminal, a call control device, and a communication program that can prompt a user to appropriately respond by specifying a cause that information cannot be acquired and improve convenience in re-operation. And

  In order to achieve the above object, the invention according to claim 1 is a communication requesting means for making a communication request to a call control device that performs call control in the call connection, when the call connection is established with the called communication terminal, and the communication A receiving unit that receives a communication state of the called communication terminal based on a communication request from the request unit from the call control device; and a communication state that is received by the receiving unit cannot communicate with the called communication terminal. Specifying means for specifying the cause of failure to communicate with the called communication terminal based on the communication information related to the request.

  The invention according to claim 2 is the invention according to claim 1, wherein the specifying unit detects a communication history with the called communication terminal from a communication history with another communication terminal, and the communication history is recorded in the communication history. Based on this, the cause is identified.

  The invention according to claim 3 is the invention according to claim 2, wherein the specifying unit is able to detect the communication history with the called communication terminal and has a communication record based on the communication history. When the cause is specified as a communication connection failure in the called communication terminal and the communication history can be detected and there is no communication record based on the communication history, the cause is specified as the absence of the called communication terminal To do.

  According to a fourth aspect of the present invention, in the second aspect of the present invention, the specifying unit is configured to detect a communication history with the called communication terminal, and a communication record in the communication history is within a predetermined period. If it is, the cause is identified as a communication connection failure in the called communication terminal.

  According to a fifth aspect of the present invention, in the first aspect of the invention, the communication request means specifies the called communication terminal for performing the call connection based on a communication terminal in a call connection destination list, and requests the communication. And the specifying unit specifies the cause as a communication connection failure in the called communication terminal when communication with the called communication terminal specified from the call connection destination list is impossible.

  The invention according to claim 6 is the notification means according to claim 1, wherein the called communication terminal notifies the call control device of a holding time for holding the registration state registered in the call control device. The call control apparatus holds the callee communication terminal until the hold time elapses after the registration period expires by the notification means notifying the hold time from the callee communication terminal. Comprising a state management means for managing as a state, wherein the reception means receives from the call control device that the communication state with the called communication terminal requested for communication by the communication request means is in a hold state, and The identifying means identifies the cause as a communication connection failure in the called communication terminal by receiving that the receiving means is in the hold state.

  The invention according to claim 7 is the invention according to any one of claims 3 to 6, wherein the communication request means is specified by the specifying means that the cause is a communication connection failure in the called communication terminal. In this case, a communication request is again made to the call control device when a call is connected to the called communication terminal.

  The invention according to claim 8 is the invention according to claim 1, wherein the receiving means receives operation instruction information together with a communication state with the called communication terminal.

  The invention of claim 9 further comprises connection means for connecting based on destination information presenting the cause related to the operation instruction information received by the receiving means in the invention of claim 8, wherein the specifying means comprises: And the cause presented to the destination based on the destination information connected by the connection means.

  According to a tenth aspect of the present invention, in the eighth aspect of the invention, the communication request unit makes a communication request again at a specified time based on the specified time communication request related to the operation instruction information received by the receiving unit.

  The invention according to claim 11 is the invention according to claim 1 or 8, wherein the call control device receives the registration request from the callee communication terminal to the callee communication terminal. Notification means for notifying the communication state of the communication terminal, and the communication request means makes a communication request for call connection with the called communication terminal to the call connection device when the communication state is notified by the notification means. .

  Further, the invention of claim 12 relates to a communication request means for making a communication request to the called communication terminal by call connection from the calling communication terminal, and a communication request by the communication requesting means when performing call control between the communication terminals. On the other hand, when the communication state detected by the state detection unit is in a state where the communication state detected by the state detection unit cannot be detected by the state detection unit that detects the communication state with the callee communication terminal, Specifying means for specifying a cause of failure to communicate with the called communication terminal based on the communication information.

  The invention according to claim 13 is the invention according to claim 12, wherein the specifying means includes a communication history with the called communication terminal in a state where the callee communication terminal cannot be detected from a communication history between communication terminals. Detect and identify the cause based on the communication history.

  According to a fourteenth aspect of the present invention, there is provided a communication request means for making a communication request to a call control device for performing call control in a call connection when the computer is connected to a callee communication terminal, and a communication request by the communication request means. Receiving means for receiving the communication state of the called communication terminal based on the call control device, and when the communication state received by the receiving means cannot communicate with the called communication terminal, the communication information related to the communication request Based on this, the cause that cannot communicate with the called communication terminal is specified.

  According to claim 1 of the present invention, there is an effect that it is possible to prompt the user to take an appropriate response by specifying the cause for which information cannot be acquired, and to improve convenience in re-operation.

  Further, according to the second aspect, there is an effect that it becomes possible to specify the cause that information cannot be acquired based on the communication history.

  Moreover, according to claim 3, there is an effect that it becomes possible to specify a detailed cause based on the communication history.

  Further, according to the fourth aspect, there is an effect that it becomes possible to specify the cause that information cannot be acquired based on the state of the communication history.

  Further, according to the fifth aspect, there is an effect that it becomes possible to specify the cause that information cannot be acquired depending on whether or not the called communication terminal is designated using the call connection destination list.

  According to claim 6, it is possible to specify that the information cannot be acquired due to a communication connection failure when the called communication terminal is in a registered state even if it is in a suspended state. The effect of becoming.

  According to the seventh aspect of the present invention, it is possible to obtain information without performing a communication request operation again when the user has recovered from a communication connection failure.

  Further, according to the eighth aspect, there is an effect that it is possible to prompt an optimum response based on information indicated in the operation instruction information even in a specific communication state.

  Further, according to the ninth aspect, there is an effect that it is possible to prompt an optimum response based on the information at the destination indicated by the destination information indicated by the operation instruction information.

  Further, according to the tenth aspect, there is an effect that it is possible to acquire information by making a communication request without performing a communication request operation again at a specified time.

  According to the eleventh aspect, by accepting a registration request from the called communication terminal that has been reserved for communication, it is possible to acquire information by making a communication request without the user performing a communication request operation again. Has the effect of becoming.

  In addition, according to the twelfth aspect, it is possible to prompt the user to take an appropriate action by specifying the cause that information cannot be acquired, and to improve convenience in re-operation.

  Further, according to the thirteenth aspect, there is an effect that it becomes possible to specify the cause that information cannot be acquired based on the communication history.

  Further, according to the fourteenth aspect, there is an effect that it is possible to prompt the user to take an appropriate response by specifying the cause that information cannot be acquired, and to improve convenience in re-operation.

An example of the block diagram of the communication system comprised by applying the communication terminal, call control apparatus, and communication program in embodiment of this invention. The figure which shows the process transition of a call connection. The figure which shows the process transition of a call connection. The figure which shows the detailed structure of the IP communication terminal in embodiment of this invention. The figure which shows the detailed structure of the call control server in embodiment of this invention. The flowchart which shows the flow of the detailed process performed by the IP communication terminal in embodiment of this invention. The flowchart which shows the flow of the process which judges as a judgment condition the designation | designated method of a destination as information regarding communication with a callee IP communication terminal. The flowchart which shows the flow of the process judged using communication history information as information regarding communication with a callee IP communication terminal. The flowchart which shows the flow of the detailed process performed by the call control server in embodiment of this invention. The figure which shows the process sequence in the case of receiving hold information from an IP communication terminal. The figure which shows the process sequence in case reference destination information is set to the call control server. The figure which shows the process sequence in case the time designation | designated is carried out. The figure which shows the processing sequence using an automatic re-request function.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of a communication terminal, a call control device, and a communication program according to the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an example of a configuration diagram of a communication system configured by applying a communication terminal, a call control device, and a communication program according to an embodiment of the present invention.

  FIG. 1 shows a communication network in which two communication networks, network A and network B, are connected by a communication line. The network A is a communication terminal that performs information communication of multimedia information such as voice and video. Call control server 200 that performs call control for establishing a communication session (session) in information communication between IP communication terminals A-1 (100A-1), IP communication terminal (100A-2) and IP communication terminals It comprises and is comprised.

  The network B includes an IP communication terminal B-1 (100B-1) and an IP communication terminal (100B-2) which are communication terminals for performing information communication of multimedia information such as voice and video. .

  Although FIG. 1 shows a network configuration in which the call control server 200 is installed only in the network A and the domains of the network A and the network B are the same, the network A and the network A are not limited to this. A configuration may be adopted in which a call control server is installed in each of the networks B, and the networks A and B constitute different domains.

  The call control server 200 receives a request for setting an IP address using DHCP (Dynamic Host Configuration Protocol) or the like from the IP communication terminal, and the like, and is used for establishing a session in information communication between the IP address and the IP communication terminal. The registrar server registers in the location server in association with (Uniform Resource Identifier). Thereby, in the location server, the correspondence relationship between the IP address and the URI as the location information (position information) (also referred to as “binding information”) of the IP communication terminal which is a user agent in the same domain of the call control server 200, Information on the valid period of the binding information is accumulated.

  This binding information is extended by performing update processing again before the validity period elapses from the IP communication terminal, and is also extended by a hold request from the IP communication terminal.

  In this way, when the correspondence relationship between the IP address and the URI is registered by the location server, when the communication request specifying the destination IP communication terminal by the URI is received from the IP communication terminal, the redirect server receives the URI. The corresponding IP address is searched in the location server, and the corresponding IP address is returned to the requesting IP communication terminal.

  As a protocol in the call control server 200, for example, H.264 is used. There are H.323 protocol and SIP (Session Initiation Protocol), and among these, a call control server using SIP is particularly referred to as “SIP server”.

  Of course, instead of providing a location server in the call control server 200 and managing the binding information, the configuration may be such that this binding information is managed by another external network device. In this case, the redirect server of the call control server 200 makes a search request for banding information to the external network device that manages the binding information, and acquires binding information corresponding to the search request.

  In addition, the binding information stored in the location server can be managed in association with the correspondence between the URI and the IP address as well as the communication information regarding the IP communication terminal.

  2 and 3 show that when a call control server 200 performs call control based on a communication request from an IP communication terminal, the caller IP communication terminal (hereinafter referred to as “calling IP communication terminal”) is called. A call connection process transition performed by a call side IP communication terminal (hereinafter referred to as a “calling side IP communication terminal”) is shown.

  FIG. 2 shows a process transition when a communication session is established by call connection between the calling side IP communication terminal and the called side IP communication terminal, and FIG. 3 shows the calling side IP communication terminal and the called side IP communication. Processing transition when a communication session cannot be established due to a call connection with a terminal is shown.

  In FIG. 2, the callee IP communication terminal makes a communication request (INVITE request) in which the callee IP communication terminal is designated by URI to the call control server, and the call control server calls the callee of the URI designated by the communication request. A communication request is transferred to the IP communication terminal. At this time, the call control server notifies the called side IP communication terminal of the status information (Trying) being called.

  Then, when a communication request is made to the callee IP communication terminal, the caller IP communication terminal sends a communication response (200 OK) to the call control server by the processing function designated by the communication request responding. Notice. In the call control server, the redirect server searches the location server for the IP address corresponding to the URI specified in the communication request, generates a communication response including the IP address, and transfers it to the requesting IP communication terminal.

  Thereby, the calling IP communication terminal acquires the IP address of the called IP communication terminal, and establishes a session by transmitting ACK information to the called IP communication terminal indicated by the IP address.

  Thereafter, the calling-side IP communication terminal and the called-side IP communication terminal perform data communication using a higher-level protocol.

  Subsequently, in FIG. 3, as in FIG. 2, the calling IP communication terminal makes a communication request (INVITE request) in which the called IP communication terminal is designated by the URI to the call control server.

  At this time, the call control server notifies the calling side IP communication terminal of the status information (Trying) being called.

  The call control server transfers the communication request to the callee IP communication terminal of the URI specified by the communication request. At this time, as shown in FIG. 3A, if the URI cannot be found due to an incorrect specification or the like, the communication request cannot be transferred and a “404 NotFound notification” is made to the calling side IP communication terminal.

  As shown in FIG. 3 (b), after transferring the communication request, the call control server enters a waiting state for a communication response from the called IP communication terminal. If not received, “404 NotFound Notification” is made to the called IP communication terminal.

  This “404 NotFound notification” is not found when the called IP communication terminal corresponding to the communication request from the calling IP communication terminal is disconnected or not activated, and the URI is not found in the SIP server. This is a notification indicating that there was no event.

  FIG. 4 is a diagram showing a detailed configuration of the IP communication terminal in the embodiment of the present invention.

  4, the IP communication terminal 100 includes a receiving unit 101, an analysis unit 102, an information control unit 103, a history search unit 104, a destination designation method determination unit 105, a history storage unit 106, a cause identification unit 107, and a call connection processing unit 108. A processing information creation unit 109, a transmission unit 110, and a user interface 111.

  The call connection processing unit 108 in the caller IP communication terminal creates a communication request (INVITE request) in which the URI of the callee IP communication terminal is designated at the time of call connection with the callee IP communication terminal. The request is transmitted to the call control server via the transmission unit 110.

  The called IP communication terminal receives a communication request from the call control server by the receiving unit 101 and notifies the analyzing unit 102 of the communication request. When the analysis unit 102 analyzes that the received information is a communication request, the analysis unit 102 notifies the call control processing unit 108.

  At this time, the call control processing unit 108 creates a communication response after confirming the status of the function requested for communication, and notifies the transmission unit 110 of the communication response. The transmission unit 110 transmits the communication response created by the call control processing unit 108 to the call control server.

  In this way, a session is established between the calling IP communication terminal and the called IP communication terminal via the call control server. Thereafter, the caller IP communication terminal and the callee IP communication terminal perform direct communication using the upper protocol.

  Further, the call connection processing unit 108 requests the call control server to update the valid period after a certain period of time in order to register the binding information registered in the location server of the call control server.

  Further, the call connection processing unit 108 can make a hold request to which the processing information created by the processing information creation unit 109 is added in order to shift the binding information registered in the location server to the hold state. In this case, when the call control server receives the hold request, the registrar server holds the binding information based on the processing information.

  When the state of the IP communication terminal is set to the hold state by this hold request, “Expires: 86400” is processed as processing information together with the hold request “REGISTER sip: reg.example.com SIP / 2.0” from the IP communication terminal to the call control server. , Contact: <sip: xxx@xx.xx.xx.xx>: expires = 0> ”is transmitted.

  As a result, the call control server places the IP communication terminal “xxx@xx.xx.xx.xx” on hold (pending state) for “86400 seconds” (24 hours).

  Further, when the call control server transmits a communication request transmitted from the call connection processing unit 108 to the call control server via the transmission unit 110 in the calling IP communication terminal, to the called IP communication terminal, When a response to the communication request is not made from the called IP communication terminal for a certain period of time or when the communication request cannot be received because the URI is not found due to a wrong specification, the calling IP communication terminal Receives a 404 NotFound notification from the call control server via the receiving unit 101.

  In the call control server, it is possible to add information that causes a failure to communicate with the called IP communication terminal to the 404 NotFound notification.

  For example, when the information about the called IP communication terminal specified in the communication request is not registered in the location server of the call control server, the item “warn-code” is added as additional information to be added to the header information of the 404 NotFound notification. By specifying “Warning 390 SIP server name“ Not Recorded ””, it is possible to notify that the called IP communication terminal does not exist on the network.

  In addition, when information such as communication hold, communication rejection, communication failure, etc. is registered as the communication state of the called IP communication terminal in the location server, “warn-code” is added as additional information to be added to the header information of the 404 NotFound notification. By specifying “Warning 390 SIP server name“ Not Ready ”” in the item, it is possible to notify that the communication failure has occurred to the called IP communication terminal.

  At this time, the receiving unit 101 notifies the 404 NotFound notification to the analyzing unit 102, and when the analyzing unit 102 analyzes that the received information is a 404 NotFound notification, the 404 NotFound notification is transferred to the information control unit 103.

  The information control unit 103 performs control processing of information related to the cause of the inability to establish a session with the called IP communication terminal based on the communication information in the 404 NotFound notification. The information control unit 103 includes a history search unit 104 and a destination designation method determination unit 105, and when the additional information such as “warn-code” item is not added to the header information of the 404 NotFound notification, Information control processing is performed based on the search unit 104 and the destination designation method determination unit 105.

  The history search unit 104 searches the communication history with the called IP communication terminal that is the notification source of the 404 NotFound notification for the communication information of the 404 NotFound notification.

  The history search unit 104 searches whether the communication history stored in the history storage unit 106 includes the communication history with the called IP communication terminal. The history storage unit 106 stores communication history information such as communication date / time, communication time, and communication state in association with the communication terminal ID, URI, and IP address for identifying the called IP communication terminal. The history storage unit 106 is not stored in the IP communication terminal, but is stored in a database (not shown) on the network, and the call control server is managed and stored for each IP communication terminal. It is possible to adopt a simple configuration. In this case, the called IP communication terminal inquires about the communication history information from the storage source, and searches from the communication history information responded to the inquiry.

  The history search unit 104 searches the communication history information based on the URI of the called IP communication terminal, and the call control server returns the IP address of the called IP communication terminal as a 404 NotFound notification for the communication history information. The communication history information may be searched based on the IP address.

  Furthermore, a search condition for communication history information can be set in the history search unit 104, and a communication history with the called IP communication terminal that matches the search condition is searched. As an example of this search condition, it is specified by the period of communication history information to be searched, and the history search unit 104 searches whether communication history information exists within the search period. In this case, even if there is communication history information with the called IP communication terminal, if there is no communication history information within the search period defined by this search condition, there is no communication history information. To do.

  The destination designation method determination unit 105 constituting the information control unit 103 holds the destination designation information and destination information used when the call connection processing unit 108 designates the called IP communication terminal at the time of call connection. The destination designation method is determined based on this destination designation information.

  As a method for designating the called IP communication terminal in the call connection processing unit 108, there is a method for designating the called IP communication terminal by direct input, or a method for designating using a call connection destination list such as an address book. is there. The destination designation information is information indicating whether the designation method of the called IP communication terminal is direct input or a method using a call connection destination list.

  Then, the information control unit 103 determines that the communication history with the called IP communication terminal exists by the history search unit 104 and the destination designation method determination unit 105 determines that the destination designation method is a method using the call connection destination list. If this is the case, the cause identifying unit 107 is notified of this.

  At this time, the cause identifying unit 107 indicates that the communication error with the called IP communication terminal for which the 404 NotFound notification has been made is caused by a communication connection failure occurring in the called IP communication terminal. Identify.

  Further, the information control unit 103 determines that the communication history with the called IP communication terminal does not exist by the history search unit 104 and the destination designation method determination unit 105 determines that the destination designation method is a method using direct input. In such a case, the fact is notified to the cause identifying unit 107.

  At this time, the cause identifying unit 107 identifies that the communication error with the called IP communication terminal for which the 404 NotFound notification has been made is caused by the absence of the called IP communication terminal on the network.

  On the other hand, when additional information is added to the header information of the 404 NotFound notification received from the call control server, the information control unit 103 includes the history search unit 104 and the destination designation method determination unit 105 included in the information control unit 103. The additional information is notified to the cause identifying unit 107 without using the information according to.

  As a result, the cause identifying unit 107 identifies the cause of the 404 NotFound notification based on the additional information.

  That is, when the additional information is “Warning 390 SIP server name“ Not Recorded ””, it is determined that the called IP communication terminal does not exist on the network, and the additional information is “Warning 390 SIP server name”. In the case of “Not Ready”, it is specified that the cause is that a communication failure has occurred in the called IP communication terminal.

  The cause identifying unit 107 displays information that causes a 404 NotFound notification on a display that constitutes the user interface 111. For example, if it is determined that a communication failure has occurred, a message “Please check the status of the communication destination device and then perform the operation again” is displayed. In addition, when it is determined that the cause is not on the network, a message “The communication destination cannot be found. Check the destination and enter the correct destination.” Is displayed.

  It should be noted that when the “Error-Info” header is added to the header information of the 404 NotFound notification and the error detail display information is added, the information displayed by the “Error-Info” header or the information displayed on the display screen of the user interface 111 The information at the reference destination indicated by the information is displayed. For example, “Saturday and Sunday cannot be received. Please send it after 8:00 am on Monday.” Or “It is just being maintained. Please send it to the number [xx-xxxx-xxxx].” .

  In addition, a “Retry-after” header and a specified time are added to the header information of the 404 NotFound notification (for example, “Retry-after: 1800”), and if the specified time re-request information is added, the user interface 111 is displayed. The display indicates that the time is specified and the specified time.

  In addition, when the identified cause is “a communication failure has occurred in the called IP communication terminal”, the cause specifying unit 107 again sends the called IP communication terminal to the call connection processing unit 108. Is instructed to make a communication request. At this time, the call connection processing unit 108 passes after a certain time (a certain time after the hold time elapses in the case of the hold state) from the transmission of the immediately previous communication request (INVITE request) (for example, after 30 minutes have passed). Again, a communication request is made to the called IP communication terminal. A re-communication request (redial process) is performed by using the destination information held by the destination designation method determination unit 105 as the destination at this time.

  Further, the call connection processing unit 108 receives the 404 NotFound notification at the receiving unit 101, and the analysis unit 102 notifies the analysis unit 102 that the 404 NotFound notification is included and the header information indicates permission event information. Thus, the automatic re-request reservation notification is sent to the call control server.

  For example, the analysis unit 102 analyzes that the permitted event information is indicated by setting “Allow-Events: dialog,...” In the header information. SUBSCRIBE EVENT: dialog "and automatic re-request reservation notification.

  At this time, in the call control server, when a registration request is received from the called IP communication terminal for which 404 NotFound notification is to be performed, a notification to that effect is set.

  When the call control server receives the registration request from the called IP communication terminal and notifies the calling IP communication terminal that the registration request has been received, the call connection processing unit 108 makes an automatic re-request.

  FIG. 5 is a diagram showing a detailed configuration of the call control server in the embodiment of the present invention.

  5, the call control server 200 includes a receiving unit 201, a call control unit 202, a storage unit 203, an update processing unit 204, a time limit management unit 205, an IP communication terminal information storage unit 206, an information creation unit 207, a transmission unit 208, An update registration unit 209 and an information search unit 210 are provided.

  The IP communication terminal information storage unit 206 stores binding information related to IP communication terminals in the unique domain. As the terminal information, the URI and IP address of the IP communication terminal are stored in association with each other, and the communication state of the IP communication terminal is added and stored.

  The IP communication terminal information storage unit 206 can store a communication history with each IP communication terminal, and stores the same communication history as that stored in the history storage unit 106 of the IP communication terminal shown in FIG. To do.

  The term management unit 205 deletes the binding information based on the expiration date of the binding information of the IP communication terminal stored in the IP communication terminal information storage unit 206, and performs the term management for invalidation. When the binding information is in the hold state, the deadline management is performed after the hold state has elapsed.

  The receiving unit 201 receives a binding information update request, a registration request, and a request for shifting to a hold state from the IP communication terminal, and notifies the call control unit 202 of the request.

  The call control unit 202 makes a processing request to the information processing unit 204 when the receiving unit 201 determines that such information has been received. The update registration unit 209 of the information processing unit 204 updates and registers the information of the IP communication terminal stored in the IP communication terminal information storage unit 206, and shifts the communication state of the IP communication terminal to the hold state.

  When an IP communication terminal registration request is received from the IP communication terminal, the update registration unit 209 of the information processing unit 204 manages the IP address and URI of the IP communication terminal in association with each other and sets a valid period. It registers in the IP communication terminal information storage unit 206. Also, when the renewal request is received, the valid period is extended.

  Further, when information “Expires: 86400, Contact: <sip: xxx@xx.xx.xx.xx>: expires = 0>” is received as processing information from the IP communication terminal, the information processing unit 204 receives the URI. The communication state of the IP communication terminal with “xxx@xx.xx.xx.xx” is set to the hold state (pending state) for “86400 seconds” (24 hours).

  FIG. 10 shows a processing sequence of a response to a communication request to the callee IP communication terminal in the hold state when the information to be put on hold is received, and will be described below.

  Furthermore, the information processing unit 204 can set a binding information hold period. When this hold period is set and the expiration date managed by the time limit management unit 205 has passed, The communication state is put on hold for a certain period.

  When the receiving unit 201 receives a communication request (INVITE request) from the calling side IP communication terminal, the receiving unit 201 notifies the call control unit 202 of the communication request. The call control unit 202 determines whether the called IP communication terminal specified in the communication request belongs to a unique domain (also referred to as “responsible domain”) using the domain table. This is notified to the transmission unit 208 and transmitted to another call control server for exchanging information regarding the domain table by the proxy server.

  If the called IP communication terminal specified in the communication request belongs to the unique domain, the information processing request is sent to the information processing unit 204. The information processing unit 204 includes an update registration unit 209 and an information search unit 210. The information search unit 210 stores an incoming call stored in the IP communication terminal information storage unit 206 based on an information processing request from the call control unit 202. The information of the side IP communication terminal is searched.

  The IP communication terminal information storage unit 206 stores binding information related to IP communication terminals in the unique domain. As the terminal information, the URI and IP address of the IP communication terminal are stored in association with each other, and the communication state of the IP communication terminal is added and stored.

  The IP communication terminal information storage unit 206 can store a communication history with each IP communication terminal, and stores the same communication history as that stored in the history storage unit 106 of the IP communication terminal shown in FIG. To do.

  Of course, the communication history is not stored in the history storage unit 106 of the IP communication terminal, but the communication history is stored only in the IP communication terminal information storage unit 206 of the call control server 200, and a search request for the communication history is sent from the IP communication terminal. By receiving the information, the information search unit 210 of the information processing unit 204 of the call control server 200 searches the communication history information stored in the IP communication terminal information storage unit 206 and responds when there is corresponding information. Good.

  When information on the called IP communication terminal is searched by the information search unit 210, the information processing unit 204 notifies the call control unit 202 of the IP address information for the URI included in the communication request, and the information search unit 210 notifies the information creating unit 207 that the information on the called IP communication terminal has been retrieved. The information creation unit 207 creates additional information based on the communication state added to the information, and notifies the call control unit 202 of the additional information. When the communication state of the called IP communication terminal is in the hold state, the information creation unit 207 creates information indicating that the IP communication terminal is in the hold state, and notifies the call control unit 202 of the information.

  The call control unit 202 adds the additional information created by the information creation unit 207 to the IP address information for the URI notified from the information processing unit 204, and transmits it to the calling IP communication terminal that has made the communication request. The data is transmitted via the unit 208.

  Further, when the information retrieval unit 210 cannot retrieve the information on the called IP communication terminal (binding information and communication history information), the information processing unit 204 notifies the call control unit 202 to that effect. At this time, the call control unit 202 requests the information creation unit 207 to create a “404 NotFound notification”, and the information creation unit 207 creates a 404 NotFound notification and responds to the call control unit 202.

  The call control unit 202 transmits a 404 NotFound notification to the called IP communication terminal via the transmission unit 208.

  FIG. 6 is a flowchart showing a detailed flow of processing performed by the IP communication terminal according to the embodiment of the present invention.

  In FIG. 6, the IP communication terminal makes a communication request (INVITE request) to the call control server (601), and receives a response from the call control server. It is determined whether a response has been received (602). If no response has been received (NO in 602), the process waits until it is received. If a response is received (YES in 602), it is determined whether the response is a 404 NotFound notification (603), and if it is not a 404 NotFound notification (NO in 603), the process ends.

  When a 404 NotFound notification is received (YES in 603), it is determined whether there is additional information in the notification (604).

  If additional information is added (YES in 604), it is determined whether the information is the cause of communication failure (605). If information on the cause of the inability to communicate is added (YES in 605), a notification such as displaying the cause information on a display or the like is performed (606).

  Then, it is determined whether or not the cause is a communication connection failure (607). If the cause is not a communication connection failure (NO in 607) and there is no incoming IP communication terminal, the process is terminated. . If the cause is a communication connection failure (YES in 607), a certain time is counted (608), and it is determined whether the certain time has passed (609).

  The predetermined time is counted until the predetermined time elapses, and when the predetermined time elapses (YES in 609), a communication request is made again to the call control server (601), and the above processing is repeated. Do.

  On the other hand, when the additional information is added to the 404 NotFound notification and the additional information is information indicating a cause of failure to communicate with the callee IP communication terminal, it is not information indicating a cause of communication failure ( Next, it is determined whether it is reference destination information (link information) referring to information indicating the cause (NO in 605) (614).

  If it is reference destination information (YES in 614), information indicating the cause is accessed based on the reference destination information (615). Then, information indicating the cause is acquired (616), and the cause of the 404 NotFound notification is specified (617). Then, it is determined whether or not the identified cause is a communication connection failure (607). If the cause is not a communication connection failure (NO in 607), and if there is no incoming IP communication terminal, processing is performed. finish.

  If the cause is a communication connection failure (YES in 607), a certain time is counted (608), and it is determined whether the certain time has passed (609). As described above, the predetermined time is counted until the predetermined time elapses. When the predetermined time elapses (YES in 609), a communication request is made again to the call control server (601), and the above processing is performed. Repeat this step.

  If the additional information is not reference destination information (NO in 614), it is subsequently determined whether or not the specified time information is added as additional information (618). If the designated time information is set (YES in 618), the designated time is counted (619), and a communication request is made again to the call control server when the designated time is reached (619). 601).

  If the designated time information is not added as additional information (NO in 618), the process ends.

  Next, a case will be described in which 404 NotFound notification is made from the call control server and additional information is not added (NO in 604) by the process of determining whether additional information is added.

  In this case, a determination process based on information related to communication with the called IP communication terminal is performed (610). The detailed flow of this determination process is shown in FIGS.

  FIG. 7 is a flowchart showing a flow of processing for determining, as information regarding communication with the called IP communication terminal, a destination designation method as a determination condition.

  In FIG. 7, the method of specifying the called IP communication terminal with the calling IP communication terminal as information relating to communication with the called IP communication terminal is not a direct input, but a method using a call connection destination list. Is determined as a determination condition (701). If it is specified using the call connection destination list (address book) (YES in 701), it is set that the judgment condition is met and the judgment condition is met (702).

  If this determination condition is not satisfied (NO in 701), a process of determining using communication history information (FIG. 8) is executed. (703).

  FIG. 8 is a flowchart showing a flow of processing to be determined using communication history information as information related to communication with the called IP communication terminal.

  In FIG. 8, the communication history information with the called IP communication terminal is searched (801). As shown above, the communication history information is stored in the call control server in addition to being stored in the IP communication terminal as described above. Makes a search request for communication history information to the call control server, returns the result by searching the communication history stored in the call control server, and returns the communication history information if there is a matching communication history. To do.

  It is determined whether or not the communication history of the called IP communication terminal has been searched by this search processing (802). If the communication history is searched (YES in 802), then the communication history within a certain period is displayed. It is determined whether it exists (803). If there is a communication history within a certain period (YES in 803), the communication history information is set to meet the conditions for determination (804).

  On the other hand, when the communication history information is not searched by the search process (NO in 802), and when the communication history information does not exist even if the communication history information is searched (NO in 803). Is set not to meet the judgment condition (805).

  In this way, when the determination process based on the information related to the communication with the called IP communication terminal is performed by the processes as shown in FIGS. 7 and 8, it is subsequently determined whether or not the determination condition is met. (611).

  When it is determined that the determination condition is satisfied by the determination processing shown in FIGS. 7 and 8 and the determination condition is set (YES in 611), the cause of the 404 NotFound notification is determined as the callee IP. It is specified that a communication connection failure has occurred in the communication terminal (612).

  On the other hand, if it is determined that the determination condition is satisfied by the determination process and it is not set to match the determination condition (NO in 611), the cause of the 404 NotFound notification is indicated by the called IP communication terminal. It specifies that it is because it does not exist (613).

  FIG. 9 is a flowchart showing a detailed flow of processing performed by the call control server in the embodiment of the present invention.

  In FIG. 9, when a communication request (INVITE request) is received from an IP communication terminal (901), it is subsequently determined whether the domain indicated by the URI of the IP communication terminal that has made the communication request is a unique domain ( 902). If the call control server stores the IP address for the URI (YES in 902), the registered binding information is searched (903).

  On the other hand, if it is not the unique domain (NO in 902), the communication request received from the IP communication terminal is transferred to another call control server designated in advance (916).

  Then, it is determined whether the binding information has been searched as a result of searching for the banding information (904). If the binding information is searched (YES in 904), then the called IP communication terminal requested for communication is subsequently sent. Is in a communicable state (917), and in the communicable state, a communication response specifying the IP address for the URI specified in the communication request is made, and the communication request is made. It transmits to the IP communication terminal (918).

  If it is not determined that the called IP communication terminal requested for communication is in a communicable state (NO in 917), it is determined whether the IP communication terminal whose binding information is retrieved is in a hold state. (905). If it is in the hold state (YES in 905), a 404 NotFound notification with information indicating that the called IP communication terminal is in the hold state is created (906).

  The 404 NotFound notification is transmitted to the IP communication terminal that has made the communication request (910).

  If the binding information cannot be searched as a result of searching for the binding information (NO in 904), it is subsequently determined whether or not error information creation is set (907).

  If it is set (YES in 907), a 404 NotFound notification with error information indicating that the binding information of the requested IP communication terminal is not stored is created (908). The 404 NotFound notification is transmitted to the IP communication terminal that has made the communication request (910).

  On the other hand, if the error information creation setting is not made (NO in 907), a 404 NotFound notification without additional information or the like is created (909), and the 404 communication for which the 404 NotFound notification has been requested for communication is generated. Transmit to the terminal (910).

  Subsequently, when the binding information is stored and it is determined that the IP communication terminal is not in the hold state (NO in 905), the following processing is performed.

  It is determined whether or not it is set to create reference destination information (link information) for information that causes communication with the called-side IP communication terminal (911), and it is set to create reference destination information. If it is determined (YES in 911), reference destination information is created (914), and a 404 NotFound notification with the reference destination information added as additional information is created (915). Then, the 404 NotFound notification is transmitted to the IP communication terminal that has made the communication request (910).

  If creation of reference destination information is not set (NO in 911), it is subsequently determined whether or not time designation is set (912). If the time designation is not set (NO in 912), a 404 NotFound notification with information indicating the processing capability of the call control server is created (909).

  As information indicating the processing capability of the call control server at this time, there is information indicating whether or not the call control server has an Auto-Retry function (automatic re-request function). Is set in Allow-Events of the header of this 404 NotFound notification.

  Then, the 404 NotFound notification is transmitted to the IP communication terminal that has made the communication request (910).

  In addition, when the time designation is set by judging whether the time designation is set (YES in 912), the time after the holding time elapses is set in the Retry-After item of the header. 404 NotFound notification is created (913).

  For example, when “Retry-After: 1800” is set, the time after 1800 seconds is specified.

  Then, the 404 NotFound notification is transmitted to the IP communication terminal that has made the communication request (910).

  FIG. 10 is a diagram showing a processing sequence in a case where hold information is received from an IP communication terminal.

  In FIG. 10, the IP communication terminal sends “REGISTER sip: reg.example.com SIP / 2.0”, “Expires: 86400, Contact: <sip: xxx@xx.xx.xx.xx>: The information “expires = 0>” is transmitted.

  Thus, the call control server sets the IP communication terminal “xxx@xx.xx.xx.xx” to the hold state for “86400 seconds” (24 hours).

  As a result, the call control server receiving the communication request with the IP communication terminal in the hold state of 86400 seconds as the called IP communication terminal issues the information “Waring: 390 reg.example.com“ Not Ready ””. To the other IP communication terminal.

  That is, it indicates that a communication connection failure has occurred.

  FIG. 11 is a diagram illustrating a processing sequence when the reference destination information is set in the call control server.

  In FIG. 11, when the calling IP communication terminal makes a communication request to the call control server, the call control server searches the binding information of the called IP communication terminal for the IP address corresponding to the URI specified in the communication request. If not retrieved, the 404 NotFound notification is transmitted with the reference destination information added to the Error-Info item of the header.

  Upon receiving this, the calling IP communication terminal sends an ACK notification to the call control server.

  Then, the calling IP communication terminal makes an information acquisition request based on the added reference destination information. In the case shown in FIG. 11A, the reference destination indicated by the reference destination information is the information management server, and the caller IP communication terminal can acquire the information by receiving an information acquisition response from the information management server. It becomes like this.

  Also, in the case shown in FIG. 11B, the reference destination indicated by the reference destination information is the call control server, and the information is acquired when the calling side IP communication terminal receives an information acquisition response from the call control server. become able to.

  FIG. 12 is a diagram showing a processing sequence when time is specified.

  In FIG. 12, when the calling IP communication terminal makes a communication request and receives a 404NotFound notification from the call control server, when "Retry-After: 1800" is specified in the header of the 404NotFound notification, The designated time is 1800 seconds later.

  When 1800 seconds elapse, a communication request (INVITE request) is made again.

  FIG. 13 is a diagram showing a processing sequence using the automatic re-request function.

  In FIG. 13, when the calling IP communication terminal makes a communication request to the call control server, the call control server searches for binding information such as an IP address for the URI specified in the communication request. When the binding information cannot be retrieved, the call control server transmits a 404 NotFound notification to the calling IP communication terminal.

  “Allow-Events: dialog,...” Is set in the header information of the 404 NotFound notification at this time. This indicates that the calling IP communication terminal can make a communication request again.

  When the calling IP communication terminal receives the 404 NotFound notification with this header information added, it notifies “SUBSCRIBE: EVENT: dialog” to the call control server as an automatic re-request reservation notification. As a result, the call control server sets a communication reservation for this reservation notification.

  When the registration request (REGISTER request) is received from the called communication terminal that has been reserved for communication, the call control server issues a notification destination for notifying that the registration request from the called communication terminal has been received. By setting the call side IP communication terminal and notifying the call side IP communication terminal of “200 OK”, the call side IP communication terminal receives this notification.

  Then, the calling IP communication terminal that has received “NOFITY (notification of initial state)” from the call control server sets the initial state and notifies “200 OK” to the call control server.

  After that, the call control server that has received the registration request (REGISTER request) from the called IP communication terminal performs “NOTIFY (notification of ready state)” to the calling IP communication terminal, and the dialog Notify the end of event notification.

  When the calling side IP communication terminal receives this “NOTIFY (notification of ready state)”, it detects that the called side communication terminal is registered, and the calling side IP communication terminal sends the call control server to the call control server. “200 OK” is notified.

  As a result, the calling IP communication terminal makes a communication request (INVITE request) again.

  The embodiment described above is one embodiment of the present invention, and is not limited to these examples, and can be implemented with appropriate modifications within a range not changing the gist thereof.

  In the present invention, the program is executed from a recording medium (CD-ROM, DVD-ROM, etc.) storing a program for executing the above-described operation or configuring the above-mentioned means in a communication system having a communication function. It is also possible to configure a communication system that executes the above-described processing by installing it in a computer and executing it. A computer constituting the communication system is connected to a CPU (Central Processor Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and a hard disk via a system bus. The CPU performs processing using the RAM as a work area according to a program stored in the ROM or the hard disk.

  The medium for supplying the program may be a communication medium (a medium for temporarily or fluidly holding the program such as a communication line or a communication system). For example, the program may be posted on an electronic bulletin board (BBS: Bulletin Board Service) of a communication network and distributed via a communication line.

DESCRIPTION OF SYMBOLS 100 IP communication terminal 101 Receiving part 102 Analysis part 103 Information control part 104 History search part 105 Destination designation method judgment part 106 History storage part 107 Cause identification part 108 Call connection process part 109 Processing information preparation part 110 Transmission part 111 User interface 200 Call Control server 201 Receiving unit 202 Call control unit 203 Storage unit 204 Update processing unit 205 Term management unit 206 IP communication terminal information storage unit 207 Information creation unit 208 Transmission unit 209 Update registration unit 210 Information search unit

Claims (14)

When a call connection is established with a callee communication terminal that notifies the call control device of a hold time for holding the registration state registered in the call control device, the call is held from the callee communication terminal by the notification in the call connection . Communication request means for making a communication request to a call control device for performing call control for managing the callee communication terminal in a hold state until the hold time elapses after expiration of the registration period by notification of time ;
The call control that receives the communication state of the called communication terminal based on the communication request from the call control device and that the communication state with the called communication terminal requested by the communication request is in the hold state. Receiving means for receiving from the device ;
If the received communication state cannot communicate with the called communication terminal, the reason why the called communication terminal cannot communicate with the called communication terminal when received from the call control device when the called communication terminal is on hold. A communication terminal comprising: a specifying means for specifying a communication connection failure in the called communication terminal. The communication terminal according to claim 1 , wherein the specifying unit further detects a communication history with the called communication terminal from a communication history with another communication terminal, and specifies the cause based on the communication history. . The specifying means further includes:
When the communication history with the called communication terminal can be detected and there is a communication record based on the communication history, the cause is identified as a communication connection failure in the called communication terminal, and the communication history is detected. The communication terminal according to claim 2 , wherein the cause is specified as the absence of the called communication terminal when there is no communication record based on the communication history. The specifying means is further configured to detect the cause of the communication at the called communication terminal when the communication history with the called communication terminal can be detected and the communication history in the communication history is within a certain period. The communication terminal according to claim 2, which is identified as a connection failure. The communication request means performs the communication request by designating the called communication terminal that performs the call connection based on a communication terminal in a call connection destination list,
The communication terminal according to claim 1 , wherein the specifying unit further specifies the cause as a communication connection failure in the called communication terminal when communication with the called communication terminal specified from the call connection destination list is impossible. . When the cause is specified as a communication connection failure in the called communication terminal by the specifying means, the communication requesting means again sends the call control device to the call control device when making a call connection with the called communication terminal. The communication terminal according to claim 1, wherein a communication request is made. The communication terminal according to claim 1 , wherein the receiving unit receives operation instruction information together with a communication state with the called communication terminal. Further comprising a connecting means for connecting based on the destination information presenting the cause of the operation instruction information received by said receiving means,
The communication terminal according to claim 7, wherein the specifying unit further specifies the cause presented to a destination based on destination information connected by the connection unit. The communication terminal according to claim 7, wherein the communication request unit makes a communication request again at a specified time based on a specified time communication request related to the operation instruction information received by the receiving unit. If you can not communicate with the called communication terminal further comprises a reservation setting means for setting a communication reservation with該着called communication terminal,
The call control device is configured to notify a reservation source communication terminal of a communication state of the callee communication terminal by receiving a registration request from the callee communication terminal for which communication reservation is set by the reservation setting means. Comprising
It said communication request means, the communication terminal according to claim 1 or 7 performs a communication request in the call connection to the called communication terminal to the call connection unit by the communication state is notified by the notification unit. A communication request means for making a communication request to the called communication terminal that notifies the call control device of a holding time for holding the registration state registered in the call control device ;
State management means for managing the callee communication terminal as a hold state until the hold time notified from the callee communication terminal elapses;
If the communication request is received by the called communication terminal managed as the hold status by the status management means, the cause of the communication failure in the called communication terminal is the reason why the call cannot be communicated with the called communication terminal. And a specifying means for specifying. The specifying means further detects a communication history with the called communication terminal in a state where the called communication terminal cannot be detected from a communication history between communication terminals, and specifies the cause based on the communication history. The call control device according to claim 11 . Computer
When a call connection is established with a callee communication terminal that notifies the call control device of a hold time for holding the registration state registered in the call control device, the call is held from the callee communication terminal by the notification in the call connection . A communication request means for making a communication request to a call control device for performing call control for managing the called communication terminal in a hold state until the hold time elapses after expiration of the registration period by notification of time ;
The call control that receives the communication state of the called communication terminal based on the communication request from the call control device and that the communication state with the called communication terminal requested by the communication request is in the hold state. receiving means for receiving from the device,
If the received communication state cannot communicate with the called communication terminal, the reason why the called communication terminal cannot communicate with the called communication terminal when received from the call control device when the called communication terminal is on hold. A communication program that functions as a specifying means for specifying a communication connection failure in the called communication terminal . Computer
  A communication request means for making a communication request to the called communication terminal for notifying the call control device of a holding time for holding the registration state registered in the call control device;
State management means for managing the callee communication terminal as a hold state until the hold time notified from the callee communication terminal elapses;
If the communication request is received by the called communication terminal managed as the hold status by the status management means, the cause of the communication failure in the called communication terminal is the reason why the call cannot be communicated with the called communication terminal. Identifying means to identify
Communication program to function as.

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