JP2010220102A - Communication system, server device, terminal and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology which can establish priority communication reliably with the terminal of an optional partner based on the input of trigger information from a terminal on the call origination side. <P>SOLUTION: In an IP telephone system having terminals and a server 2 which processes the requests from the terminals, and transmitting and receiving data among a plurality of terminals over a network, a terminal 3A sets priority communication identification information indicating priority communication in the INVITE which requests establishment of session with the other terminal 3B when the trigger information relating to the start of priority communication is detected. A repeater existing between the terminal 3 and the server 2 on the network transmits a packet to the INVITE in which the priority communication identification information is set while attaching control information for decreasing the probability of cancellation even in the congestion state. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication system, a server device, a terminal device, and a program used in the server device and the terminal device that transmit and receive data between terminal devices using an IP (Internet Protocol) network.

  There is VoIP (Voice over Internet Protocol) as a technique for transmitting and receiving voice data using an IP network. VoIP provides a maximum bandwidth of 1 Gbps, for example, when technology such as Gigabit Ethernet is used on an optical communication network.

  When a failure such as a physical disconnection of a normally used optical communication network occurs due to a disaster or the like, the network is switched to an alternative network. When the price network is a low-speed network such as a wireless network, the available bandwidth is several tens of M to several Mbps, and is degenerated to one-hundredth. In addition to voice data, a large amount of data such as image data flows into the alternative network, making it difficult to secure a call.

  As a known technique for ensuring communication, there is provided a technique for realizing priority transfer in a control system device by changing the priority of main information in advance according to the content of communication of a terminal device. Specifically, a priority symbol indicating the priority degree of main information is generated in the control system device (server). In a transfer system device, a technique for performing priority transfer by translating into control parameters necessary for controlling main information from priority symbols and assigning to the main information is provided (for example, Patent Document 1). .

JP 2006-246144 A

  In the above known technique, the possible priority communication pattern is fixed depending on the contents of the table held by the control system device. That is, a person who performs communication can only establish fixed priority communication with a terminal device described in a table held by the control system device.

  For example, if a call is made to make a priority call from a fixed terminal to a fixed partner (fixed partner terminal device) using VoIP, but the called party is busy, the control system device , There is a case where a call is made to another terminal device for which priority call is not set. When such a call is made at the time of degeneration of the network or the like, the call quality cannot be sufficiently ensured as in the case of making a priority call.

  Further, when the network is degenerated, a relay device such as a router discards a packet having a low priority. Therefore, even if the control system device stores the IP address of the fixed terminal with high priority, the INVITE packet from the fixed terminal is discarded in the router on the way from the fixed terminal to the control system device. In such a case, since the INVITE packet from the fixed terminal cannot reach the control system device in the first place, it is natural that the priority call cannot be started.

  It is an object of the disclosed program to provide a technique capable of determining priority communication in a terminal device on the originating side and establishing priority communication with an arbitrary terminal device of a counterpart.

  According to the disclosed communication system, the communication device includes a terminal device and a server device that processes a request from the terminal device, and transmits and receives data between a plurality of terminal devices via a network. A setting means for setting priority communication identification information indicating priority communication in a packet indicating a session establishment request with another terminal device when trigger information related to the start of priority communication is detected; A packet indicating a session establishment request in which the priority communication identification information is set by the setting unit is discarded even in a congestion state in the relay device existing between the terminal device and the server device on the network. And a transmission means for transmitting the control information with a lower probability, and the server device receives the session establishment request from the terminal device. When the determination means determines whether or not the priority communication identification information is included in the session establishment request, the determination means indicates the session establishment request determined to include the priority communication identification information. In the relay device existing between the server device and the terminal device on the network, the packet is attached to the session establishment request with control information so that the discard probability is low even in a congested state. Sending means for sending to the terminal device that is included, and a series of sessions started based on the session establishment request determined by the determining means to include the priority communication identification information as other sessions Storage means for storing information for identification.

  When the terminal device detects the trigger information related to the priority communication start, the terminal device indicates the session establishment request in which the priority communication identification information is set, including the priority communication identification information indicating the priority communication in the session establishment request. Packets are transmitted (with high priority) with information such that the discard probability is low even in a congestion state such as when the network is degenerated. When the information indicating that priority communication is included in the session establishment request, the server device transmits the session establishment request with high priority to the destination terminal device with high priority. At the same time, the server device stores information for identifying a series of sessions from other sessions. The packet to be sent and received to establish a session thereafter is set to information for identifying the above session from other sessions, and the packet is related to priority communication using the above information set in the packet. Is recognized and sent with high priority. Thereby, based on the trigger information input to the originating terminal device, it becomes possible to establish the priority communication with the partner terminal device more reliably.

  According to the disclosed program, it is possible to determine the priority communication in the terminal device on the originating side and to establish the priority communication with any other terminal device of the other party more reliably.

It is a figure explaining the outline | summary of the IP telephone system which concerns on embodiment. It is a functional block diagram of a VoIP terminal. It is a functional block diagram of a SIP server. It is the flowchart which showed the determination process of the priority call in a terminal. It is a figure which shows the connection flow in priority call mode. It is a figure which shows the data format example of a SIP packet. It is a figure which shows the data format example of an audio | voice packet. It is the flowchart which showed the process which determines the received packet in a server. It is a figure explaining the method of managing a password in a server. It is the flowchart which showed the change process of the password in a terminal. It is a figure which shows the structural example of the data stored in the priority PW management DB of a terminal. It is a figure which shows the structural example of the data stored in the database of a server. It is a sequence diagram of the synchronous process in the normal time. It is a sequence diagram of the synchronization processing in the high priority mode. It is a sequence diagram of the registration process in the normal time. It is a sequence diagram of the registration process in a high priority mode. It is the flowchart which showed the registration process in a server. It is FIG. (1) explaining the exclusive process of a telephone call. It is FIG. (2) explaining the exclusive process of a telephone call. It is a block diagram of information processing apparatus. It is a figure which shows a recording medium.

Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram for explaining the outline of the IP telephone system according to the present embodiment. In the following, an IP telephone system is taken as an example of the IP communication system, and a case where voice data is transmitted / received in the IP telephone system will be described.

  An IP telephone system 1 shown in FIG. 1 includes a SIP (Session Initiation Protocol) server 2 and a plurality of VoIP terminals 3 (in FIG. 1, each VoIP terminal 3 is described as VoIP terminals 3A, 3B, 3C, and 3D). . The VoIP terminal 3 is connected to the IP network 10 as a relay device via a layer 3 switch (L3SW) 4, for example, and negotiates via the SIP server 2. When communication with the other VoIP terminal 3 is established, communication with the other VoIP terminal 3 is started.

  In the IP telephone system 1 according to the present embodiment, a process for establishing a priority call is recognized by recognizing that the operation of the VoIP terminal 3 is an operation by a person who is permitted to make a priority call (hereinafter referred to as a priority caller). To start. That is, when the priority caller inputs the trigger information via the calling party's VoIP terminal 3, each of the VoIP terminal 3 and the SIP server 2 transmits or transfers a packet related to the negotiation with high priority. Establish.

  FIG. 1 illustrates a case where the priority caller uses the VoIP terminal 3A among the four VoIP terminals 3A to 3D. When the VoIP terminal 3A detects a call start operation by a priority caller, the IP telephone system 1 transmits and receives a packet for establishing a call with the VoIP terminal 3C selected as a call destination with high priority, Establish a priority call.

  According to such a method, for example, when the priority caller first calls the VoIP terminal 3D, but the VoIP terminal 3D is in a call with the VoIP terminal 3B, and instead calls the VoIP terminal 3C. Even so, the priority caller can dynamically make a priority call from the VoIP terminal 3A to any VoIP terminal 3C.

  In the IP telephone system 1 according to the present embodiment, the VoIP terminal 3A recognizes that the trigger information serving as a trigger for the priority call is input by the priority caller. That is, it is identified whether the caller is a priority caller or a general caller who is not a priority caller. The VoIP terminal 3 </ b> A that has received the trigger information for the priority call performs negotiation for establishing the highest priority call line with the partner VoIP terminal 3 via the SIP server 2. Thereafter, the line quality is ensured by performing packet transmission / reception at the highest priority level until the call is disconnected. Hereinafter, the VoIP terminals 3A to 3D and the SIP server 2 included in the IP telephone system 1 according to the present embodiment will be specifically described.

  FIG. 2 is a functional block diagram of the VoIP terminal 3. 2 includes a RFID (Radio Frequency IDentification) receiving unit 31, an on-hook / off-hook detecting unit 32, an operation unit 33, a display display unit 34, a priority password management database (priority PW management DB). ) 35, a handset unit 36, an audio codec unit 37, a control processing unit 38, and a LAN (Local Area Network) interface unit 39.

The RFID receiving unit 31 receives the trigger information 11 from the RFID tag. In the embodiment, information for identifying the priority caller is received from the RFID tag held by the priority caller.
The on-hook / off-hook detector 32 detects whether the handset unit 36 of the terminal 3 is on-hook or off-hook.

  The operation unit 33 receives trigger information 12 and instructions input from the user of the terminal 3. In the embodiment, the password input by the priority caller is accepted. The password is set for each priority caller in the IP telephone system 1. The VoIP terminal 3 identifies a priority caller by inputting a correct password used in an emergency such as when the priority caller does not hold an RFID tag.

The display display unit 34 outputs and displays the state of the terminal 3 and the like.
The priority PW management DB 35 stores information for determining whether or not the password input via the operation unit 33 is the owner of the RFID tag for the priority person.

  The handset unit 36 includes a receiver, a transmitter, and the like. The handset unit 36 receives a voice signal input by the user of the terminal 3 by the receiver, and outputs a voice signal input from the voice codec unit 37 to the transmitter.

  The audio codec unit 37 converts the analog audio signal input from the handset unit 36 into a coded digital audio signal. Also, the voice codec unit 37 converts the coded digital voice signal received from the terminal 3 that is the call destination into an analog voice signal, and provides the analog voice signal to the handset unit 36 (transmitter).

  The control processing unit 38 gives an instruction to each function unit of the terminal 3 and controls the operation of each function unit. As processing according to the present embodiment, trigger information indicating the start of a priority call input to the terminal 3 by the operation of the priority caller is recognized, and the priority call by the priority caller is included in a packet transmitted for session establishment. Priority call identification information indicating that is set. In the embodiment, the trigger information is information or a password for identifying the RFID tag. When priority call identification information indicating that a call is a priority call is set in a packet received from the partner terminal 3, information indicating a priority call is set in a packet returned to the partner terminal 3, Send. A specific method for setting the priority call identification information will be described later.

  The packet generated by the control processing unit 38 sets the DSCP value of the IP header in the LAN interface unit 39 according to an instruction from the control processing unit 38 and sends the packet to the IP network 10. Packets transmitted and received between the terminals 3 for establishing a session are transferred to the partner terminal 3 via the SIP server 2.

  FIG. 3 is a functional block diagram of the SIP server 2. The SIP server (hereinafter abbreviated as server) 2 shown in FIG. 3 receives a packet for establishing a session from the terminal 3 and transfers it to the other terminal 3 of the communication destination. The server 2 includes a priority call determination unit 22, a priority call management database (priority call management DB) 23, a priority password management database management unit (priority PW management DB management unit) 24, a location database (location DB) 25, and a location database management unit. (Location DB management unit) 26, register unit 27, proxy unit 28, redirect unit 29, and authentication unit 30 are included.

The server 2 receives the packet transmitted by the terminal 3 shown in FIG. 2 for establishing a session via the LAN interface unit 21 and transmits the packet to another terminal 3.
The priority call determination unit 22 determines whether the call is a priority call based on the received packet. That is, whether or not the call is a priority call based on whether or not priority call identification information indicating a call by a priority caller (priority call) is set with reference to a predetermined field of a packet for session establishment Determine whether. The priority call management DB 23 stores information used to make a determination in the priority call determination unit 22.

The priority PW management DB management unit 24 manages information for identifying a priority caller.
The location DB 25 stores information for managing the registration status of each terminal 3 in the server 2. The location DB management unit 26 manages information related to registration of the terminal 3 in the location DB 25. Details will be described later.

  In response to a registration request (REGISTER) from the terminal 3, the register unit 27 executes processing related to registration. The proxy unit 28 transfers a request received from a certain terminal 3 to the terminal 3 on the other side. In response to the request from the terminal 3, the redirect unit 29 notifies the terminal 3 of the destination address of the partner terminal 3. The authentication unit 30 executes authentication processing related to registration, session establishment, and the like.

  When the server 2 shown in FIG. 3 receives a session establishment request from the terminal 3 shown in FIG. 2, the received session establishment request is based on the priority call identification information stored in a predetermined field of the received request. It is determined whether or not the call is related to a priority call. If it is determined that the session establishment request for the priority call is determined, the subsequent packets are sent to the terminal 3 with high priority. Hereinafter, a method for establishing a priority call will be specifically described.

  FIG. 4 is a flowchart showing the priority call determination process in the terminal 3. 4 is triggered by the fact that the user (caller) detects an off-hook in the on-hook / off-hook detection unit 32 of the terminal 3 of FIG. The process shown is started.

  First, in step S <b> 1, it is determined whether the RFID receiving unit 31 receives tag information. When the tag information is received, it is determined that the priority caller is trying to make a priority call by reading the RFID tag from the terminal 3, and connection processing in the priority call mode is performed. If it is determined in step S1 that tag information has not been received, the process proceeds to step S2.

  In step S <b> 2, the operation unit 33 determines whether a password related to a priority call has been input by the user. Here, it is also determined whether or not the input password matches the password registered in the priority PW management DB 35. If the correct password is entered, connection processing in the priority call mode is performed.

  If it is determined in step S2 that there is no input of a password that matches the password registered in the priority PW management DB 35 of the terminal 3, connection processing in the default call mode is performed. In the default call mode, priority is not set.

  FIG. 5 is a diagram showing a connection flow in the priority call mode. Hereinafter, with reference to FIG. 5, a description will be given of a procedure in the IP telephone system 1 according to the present embodiment when the originating terminal 3A makes an IP telephone call to the terminating terminal 3B in a priority call.

  In the following, a method for recognizing that a call is made by a priority caller and establishing a session will be mainly described, and details of session establishment processing, which is a known technique, will be omitted.

  First, the terminal 3A recognizes that a priority call start operation has been performed by a priority caller with the trigger information that tag information has been received from an RFID tag or a password has been input. When the priority call start operation is recognized, a value indicating priority call, that is, priority call identification information, is stored as session information (S type) in the message body of the SIP message in the packet of the INVITE (session establishment request) message to be transmitted. Set.

Then, the server 2 is transmitted with high priority, that is, the DSCP value of the IP header portion is set to EF (= 101110) (S101).
Here, the priority call identification information is information for recognizing that the packet is a packet related to the priority call in the server 2 or the terminal 3 without the IP header portion of the packet.

  Here, the originating terminal 3A also transmits to the server 2 information “Call-ID” for identifying the dialog between the terminal 3A and the terminal 3B from the other dialogs in the packet of the INVITE message. . A Call-ID is set for a packet transmitted and received in the subsequent sequence, and each device is set as a dialog between the terminal 3A and the terminal 3B, that is, a priority call based on the Call-ID of the received packet. Recognize that it is a dialog. The dialog is a series of sessions performed between a plurality of terminals, that is, a session including transmission of an INVITE message from a calling terminal to reception of a 200 OK message corresponding to a BYE message indicating that the session is disconnected. From start to end. The same Call-ID is used for packets related to the same dialog.

  In addition, the terminal 3A sets a value “101110” indicating that it should be forwarded with high priority in the IP network 10 (Expedited Forwarding, EF) as a DSCP value in the IP header portion of the packet to be transmitted. For example, when the network is congested due to traffic concentration on a detour route when the network is degenerated, a network device such as a router configuring the IP network 10 refers to the DSCP value and starts from a packet with a high priority. A transfer process is performed, and a discard process is performed for a packet that cannot be caught by the transfer process.

  When the server 2 receives the INVITE message, the server 2 refers to the S type set in the INVITE message in which the IP header part including the DSCP value is already deleted in the LAN interface unit 21. When the priority call identification information indicating the priority call is set in the S type, the server 2 stores the Call-ID stored in the packet of the INVITE message received from the terminal 3A in its own database. Remember me. Then, the LAN interface unit 21 sets “101110” as the DSCP value of the IP header, and sends the INVITE message to the terminal 3B with high priority (S102).

  In the subsequent flow, each device configuring the IP telephone system 1 sets the same Call-ID during the same session in the packet transmitted and received between the terminal 3A and the terminal 3B, and the DSCP value is high. A value “101110” indicating priority is set. That is, the IP telephone system 1 according to the present embodiment recognizes that communication between the terminal 3A and the terminal 3B, that is, a priority call is made by Call-ID in sending and receiving messages after INVITE. Then, a packet to be transmitted / received for establishing a priority call session is transmitted with the DSCP value of the IP header portion set to a predetermined value.

  When receiving the INVITE message, the called terminal 3B refers to the S type set in the INVITE message. When priority call identification information indicating a priority call is set in the S type, the Call-ID in the INVITE message is stored, and the DSCP value of the IP header portion of the Trying message returned to the terminal 3A Then, “101110” is set in the LAN interface unit 39 and transmitted with high priority (S103).

  When the server 2 receives the Trying message from the terminal 3B, the server 2 refers to the Call-ID in the Trying message and compares it with the retained Call-ID. If the Call-ID is the same as the Call-ID previously extracted from the INVITE message and stored, it is recognized that the Trying received from the terminal 3B is a packet transmitted and received for establishing a priority call session. In this case, the LAN interface unit 21 sets “101110” in the DSCP value of the IP header portion of the Trying message transferred to the terminal 3A, and sends it with high priority (S104).

  Thereafter, each terminal 3A, 3B refers to the Call-ID of the received message, and if it matches the Call-ID held, it has received a packet transmitted / received for establishing a priority call session. recognize. In this case, the LAN interface unit 39 sets “101110” as a value indicating high priority to the DSCP value in the IP header portion, and transmits it (S105, S107, S109). The server 2 refers to the Call-ID of the message received from the terminals 3A and 3B. If the Call-ID of the received message matches the Call-ID held, the packet is recognized as a packet for establishing a priority call session, and the LAN interface unit 21 sets the DSCP value of the IP header to a high value. “101110” is set as a value indicating priority and transmitted (S106, S108, S110).

  When the Ringing, 200OK and ACK messages are transmitted and received in the order shown in FIG. 5 between the terminal 3A and the terminal 3B via the server 2 in the order shown in FIG. 5 (S105 to S110), the terminal 3A and the terminal 3B have high priority. Start sending and receiving audio data.

  During a call, the terminal 3A and the terminal 3B directly transmit / receive voice packets to / from the other terminal using RTP (Real-time Transport Protocol). In a priority call, by setting a value indicating high priority to the DSCP value in the IP header portion, a two-way dedicated line quality call line is secured.

  When it is detected that the terminals 3A and 3B are in the on-hook state, processing for terminating the call is started. First, a BYE message is transmitted from the terminal that first enters the on-hook state (in the present embodiment, the originating terminal 3A) to the terminating terminal 3B (S111). In the LAN interface unit 39, “101110” is set in the DSCP value of the IP header, and transmission is performed with high priority.

  Similarly to the time of session establishment, when the Call-ID in the message matches the Call-ID held by the server 2, the LAN interface unit 21 sets the DSCP value of the IP header to high priority in the LAN interface unit 21, It is sent to 3B (S112).

  The terminal 3B that has received the BYE message determines whether or not the Call-ID in the message matches the Call-ID held in the same manner as when the session is established. If they match, the LAN interface unit 39 sets “101110” as the DSCP value in the IP header and transmits it with high priority (S113). Similarly, the server 2 refers to the Call-ID, determines 200 OK for the priority call, sets “101110” as the DSCP value of the IP header in the LAN interface unit 21, and sends it to the terminal 3A with high priority. (S114). When the terminal 3A receives 200 OK, a series of connection flows is completed.

  When the series of flows shown in FIG. 5 is completed, each device (terminal 3A, 3B and server 2) initializes various types of information such as S type and Call-ID held for the call, and ends the processing. To do.

  In the flow shown in FIG. 5, SIP messages transmitted and received via the server 2 such as INVITE and Trying are described in general formats such as a start line, a message header, and a message body. With regard to the priority call establishment method according to the present embodiment, each device is initially set by using the S type included in the message body of the INVITE request and setting identification information indicating that the call is a priority call in the S type. The priority call is identified. For SIP messages that do not have a message body such as Trying, the priority call is identified by Call-ID. The DSCP value is stored in the IP header part of the SIP packet and the voice packet by the LAN interface part.

  A relay device such as a router on the IP network 10 performs packet transfer processing immediately in the order of arrival of normal packets. However, when traffic exceeding the line capacity is concentrated on a detour route such as when the network is degenerated. For packets that arrive later, there is a delay that waits until the transfer of all previously arrived packets is completed. If this situation worsens, the router becomes congested and packets that cannot be processed by the router are discarded.

  In order to avoid discarding important packets due to router congestion, the router has a function to prioritize packet forwarding based on the value of the ToS field. For example, some traffic is sent using the DSCP value. It is possible to control the packet transfer order by classifying them into classes and changing the priority for each class.

  In the IP telephone system 1 according to the present embodiment, the originating terminal 3A sets priority call identification information, which is a value indicating a priority call, in an INVITE message transmitted first in the session establishment sequence. In addition, in order to reduce the probability that an INVITE message in which priority call identification information is set will be discarded even if the IP network is congested, the DSCP value in the IP header portion is set to high priority in the LAN interface portion. Is set to a value (Expedited Forwarding, EF) that increases packet transfer priority in a relay device such as a router and makes it difficult to be discarded (set control information for priority control). To do. Therefore, even if the relay device such as L3SW4 in the middle of the network path from the originating terminal 3A to the server 2 is congested, the INVITE message that the originating terminal 3A first transmits in the session establishment sequence is relayed. There is a high possibility that the server 2 can be reached without being discarded by the apparatus.

  When the priority call identification information indicating that the call is a priority call is set in the INVITE message, the server 2 and the called terminal 3B store the Call-ID in the INVITE message in the own apparatus and the INVITE message. As for the messages transmitted and received thereafter, each terminal and the server 2 recognize that the message is related to the priority call by the Call-ID. For a packet recognized as a message related to a priority call, the DSCP value in the IP header portion is set to a value indicating high priority in each LAN interface portion. As a result, even when a router or the like on the network is in a congested state, it is possible to establish a priority call more reliably and maintain the established priority call.

Next, the storage location of these pieces of information will be specifically described with reference to the packet format.
FIG. 6 is a diagram illustrating a data format example of the SIP packet. In the SIP packet, a SIP message including a message body is encapsulated with an IP header and a TCP header.

  The SIP message includes a start line, a message header, and a message body. Information for identifying a message such as INVITE or ACK is stored in the start line. Call-ID for identifying a dialog between terminals 3 (between terminals 3A and 3B in FIG. 5) is stored in the message header, and S type is stored in the message body. The S type is described in SDP (Session Description Protocol). In the embodiment, “s = tag / [tag ID]” is described. By including the tag ID of the RFID tag held by the priority caller in the S type, it is possible to reduce the probability that the same session name as the accidental priority call is set in the S type of the terminal that does not have the priority call function. .

In addition, although the Expires value regarding the registration process is also stored in the message header, details will be described later.
The DSCP value is stored in a ToS (Type of Service) field of the IP header. FIG. 6 shows the format of an IPv4 (Internet Protocol version 4) header. Since the format of the IPv4 header is publicly known, a detailed description other than the ToS field in which the DSCP value is stored is omitted here.

  FIG. 7 is a diagram illustrating a data format example of a voice packet. In the voice packet, a voice payload that is a voice data body is encapsulated by an IP header, a UDP (User Datagram Protocol) header, and an RTP header.

  In the present embodiment, the terminal 3 also stores the DSCP value “101110” indicating that the voice packet should be transferred with high priority in the ToS field of the IP header, similarly to the SIP packet of FIG. Since the IP header shown in FIG. 7 also shows a known IPv4 header format as in FIG. 6, the description of fields other than the ToS field will be omitted here.

  As described above, in the IP telephone system 1 according to the present embodiment, when a priority caller tries to make a call, the LAN interface unit 21 receives an IP header for a packet transmitted / received via the SIP server 2. The DSCP value of the part is set to “101110”. For a packet in which the DSCP value of the IP header is set to “101110”, the L3SW on the IP network transfers it with high priority.

The operation of the server 2 that relays SIP packets between the originating terminal and the terminating terminal will be described with reference to FIG.
FIG. 8 is a flowchart showing processing for determining a received packet in the server 2. The processing shown in FIG. 8 is executed by the SIP basic function units such as the priority call determination unit 22 and the proxy unit 28 that constitute the server 2 of FIG. The server 2 starts the process shown in FIG. 8 when receiving the SIP packet having the format shown in FIG. 6 from the terminal 3 (the originating side terminal 3A and the destination side terminal 3B in FIG. 5).

  First, in step S11, it is determined whether or not the received packet is an INVITE message. If it is determined that the message is an INVITE message, the process proceeds to step S12, and the S type in the SIP message is referenced to determine whether the call is a priority call. If it is determined that the call is a priority call, the process proceeds to step S13, and the Call-ID included in the INVITE packet is stored in the storage means of the server 2, for example, the priority call management DB 23 of FIG. Then, in step 14, the priority call management DB 23 is updated, the same tag call is confirmed, and it is confirmed whether it is a duplicate priority call. The priority call management DB 23 will be described in detail with reference to FIG.

  As a result of checking in step S14, if the priority call is not a duplicate, a value indicating “busy” is set for the session state of the tag ID identified by the S type. The processing in the case where it is confirmed that the priority calls are overlapping will be described in detail later with reference to FIG. 18 and FIG. 19 as call exclusion processing.

  When the session state of the priority call management DB 23 is updated in step S14, packet transfer processing is performed with high priority using a known SIP function in step S15. That is, a value indicating high priority is set in the DSCP value in the IP header of the packet to be transmitted. That is, even when a relay device such as a router is in a congested state, the packet transfer process is preferentially performed and discarded. Set to a low value and send the set packet. The high priority setting method is as described with reference to FIG.

  If it is determined in step S12 that the call is not a priority call, the process proceeds to step S20. In step S20, a normal packet transfer process (priority setting is not performed) is performed. Since a value representing the best effort is set as the DSCP value in the normal packet transfer processing, there is a high probability that the relay device such as a router is discarded when it is congested.

  If it is determined in step S11 that the received packet is other than the INVITE message, the process proceeds to step S16. In step S16, it is further determined whether or not the received SIP packet is a registration request (REGISTER). Processing when the received packet is a registration request will be described later.

  If it is determined in step S16 that the request is other than a registration request, it is determined that a message after INVITE has been received among various messages transmitted and received for session establishment, and the process proceeds to step S17. Then, referring to the Call-ID of the message header that can be recognized by the server 2 of the packet, it is determined whether or not the Call-ID is for the priority call. The determination is made based on whether or not the Call-ID stored in step S13 matches.

  If it is determined in step S17 that the call is a Call-ID for the priority call, the process proceeds to step S18. In step S18, it is determined whether or not the received SIP packet is 200OK for BYE.

  If it is determined in step S18 that the received SIP packet is other than 200 OK for BYE, it is determined that a call is in progress, and the process proceeds to step S14. Step S14 is the same as described above, the session state of the priority call management DB is maintained as “busy”, and SIP packets are transferred with high priority based on the SIP function in step S15.

  In step S18, if it is 200 OK for BYE, it is determined that the packet to be transferred at the end of the sequence shown in FIG. 5 has been received, and the process proceeds to step S19. In step S19, 200OK is transferred with high priority, and the Call-ID for the priority call held is deleted. Then, a value indicating “no call” is set in the session state of the priority call management DB 23, the process proceeds to step S20, and the normal operation (that is, priority is not set) is returned to.

  If it is determined in Step S17 that the Call-ID is not the Call-ID for the priority call as a result of checking the Call-ID, the process proceeds to Step S20, and the SIP packet is set without setting the priority based on the SIP function. Transfer.

  In the above-described embodiment, both the terminal 3 and the server 2 identify whether or not the packets are related to the same dialog using the Call-ID, but the same information is used using information other than the Call-ID. You may identify whether it is a packet regarding a dialog. For example, in step S13, a set of the IP address of the originating terminal 3A and the IP address of the terminating terminal 3B included in the INVITE packet may be stored in the priority call management DB 23. Similarly, the destination terminal 3B and the calling terminal 3A also store a set of the IP address of the calling terminal 3A and the IP address of the called terminal 3B included in the INVITE packet.

  When the set of the IP address of the calling terminal 3A and the IP address of the called terminal 3B is stored in each of the server 2, the calling terminal 3A, and the called terminal 3B instead of the Call-ID, the server 2 In each of the terminals 3A and 3B, when the set of the IP addresses of the calling side terminal 3A and the called side terminal 3B indicated in the received packet is compared with the stored set of IP addresses, they are the same Can be determined to be a packet related to a priority call. The processing after the server 2 and each of the terminals 3A and 3B determine that the packet is related to the priority call is the same as in the above embodiment. For the stored IP address set, information regarding the IP address set in the storage unit may be initialized at the timing when the Call-ID is initialized in the above-described embodiment.

  As described above, in the IP telephone system 1 according to the present embodiment, the calling terminal 3 recognizes that the call is a call by a priority caller using an RFID tag and a password, and indicates that the call is a priority call in the INVITE message. Set the type. The password is shared among the terminals 3 in the network so that the priority caller can make a priority call regardless of which terminal 3 in the IP telephone system 1 is used. The server 2 manages passwords in order to realize sharing of passwords between the terminals 3. Hereinafter, the password management method by the server 2 will be described in detail.

  FIG. 9 is a diagram for explaining an outline of a method for managing passwords in the server 2. An example will be described in which a password change instruction is input via the operation unit 33 in the terminal 3A among the plurality of terminals 3 (3A, 3B,..., 3N) constituting the IP telephone system 1.

  When the operation unit 33 of the terminal 3A accepts a password change operation by the priority caller, the terminal 3A registers the password newly set by the priority caller in the priority PW management DB 35A in the own device, and the server 2 Notify the updated password. The server 2 registers the new password notified from the terminal 3A in the priority call management DB 23 of the own apparatus, and synchronizes the priority call management DB 23 of the own apparatus and the priority PW management DB 35 of each terminal 3. As a result, the priority caller can make a priority call from any terminal 3 in the IP telephone system 1 using the password.

  The priority call function is not set depending on the terminal 3 and may not be used. Therefore, in the embodiment, the server 2 refers to information indicating whether or not each terminal 3 in the location DB 25 has the priority call function, and synchronizes the contents of the database with respect to the terminal 3 having the priority call function. Yes.

  For information indicating whether each terminal 3 has a priority call function, the server 2 registers in the location DB 25 (FIG. 3) based on the information received from the terminal 3 when the terminal 3 is registered. The registration process will be described later.

The password management method by the server 2 shown in FIG. 9 will be described more specifically with reference to FIGS.
FIG. 10 is a flowchart showing password change processing in the terminal 3. The process shown in FIG. 10 is executed by the control processing unit 38 of the terminal 3 in FIG. 2, and the control processing unit 38 of the terminal 3 receives a password change instruction via the operation unit 33 in the terminal 3A of FIG. As a trigger, the processing shown in FIG. 10 is started.

  First, in step S31, the RFID receiver 31 determines whether tag information as trigger information has been received from an RFID tag held by a priority caller. If tag information cannot be received from the RFID tag, it is determined that the operation is not performed by a priority caller, and the process proceeds to step S36. In step S36, the process for changing the password setting is canceled, and the process ends.

  If it is determined in step S31 that tag information has been received from the RFID tag, the process proceeds to step S32 to check the tag ID. Specifically, it is determined whether or not the received tag ID is registered in the priority PW management DB 35. If the tag ID is not registered in the priority PW management DB 35, the process proceeds to step S36, the password change process is canceled, and the process ends.

  If it is determined in step S32 that the received tag ID is registered in the priority PW management DB 35, the process proceeds to step S33 to accept a password change operation. In step S34, it is determined whether a password confirmation instruction has been input. If the password is not confirmed, the process proceeds to step S36, the password change process is canceled, and the process ends.

  If it is determined in step S34 that a password confirmation instruction has been input, the process proceeds to step S35, and the password input in step S33 is newly registered in the priority PW management DB 35. Further, the server 2 is notified of the changed password, and the process ends.

  FIG. 11 is a diagram illustrating a structure example of data stored in the priority PW management DB 35 of the terminal 3. The priority PW management DB 35 includes a management number (management No.), a tag ID, and a password.

The management number is identification information for identifying in the terminal 3 information registered for each priority caller.
The tag ID is identification information for identifying the RFID tag held by the priority caller. As described with reference to FIG. 9, the password is a character string including numbers and characters set through the terminal 3 by the priority caller holding the RFID tag. The password is associated with the tag ID. As a result, the terminal 3 uses the password entered via the operation unit 33 of the terminal 3 when the priority caller does not have an RFID tag, etc., so that the user who entered the password is assigned a priority call. Authenticate

  FIG. 12 is a diagram illustrating a structure example of data stored in the database of the server 2. FIG. 12A shows an example of the data structure of the priority call management DB 23, and FIG. 12B shows an example of the data structure of the location DB 25.

In the priority call management DB 23 shown in FIG. 12A, a password (PW) and a session state are associated with a tag ID.
The tag ID is identification information for identifying the RFID tag held by the priority caller. The password is a character string including numbers and characters notified from the terminal 3.

In the session state, a value indicating the connection status of the terminal used by the priority caller identified by the tag ID is stored.
In the location DB 25 shown in FIG. 12B, priority call function information, an IP address, and update information are associated with a SIP-URI (Uniform Resource Identifier).

The SIP-URI is information for identifying a communication resource using SIP, and is used for designating a destination terminal 3 in IP communication.
The priority call function information is information indicating whether or not the terminal 3 has a priority call function. In the embodiment, “1” is set when the priority call function is provided, and “0” is set when the priority call function is not provided. The priority call function information is received from the terminal 3 when the terminal 3 is registered. The registration process will be described later.

  The IP address is an identification number assigned to the terminal 3 in the IP network 10. For example, upon connection between the terminal 3A and the terminal 3B in FIG. 5 described above, when the SIP-URI of the terminal 3B that is the call destination is received from the terminal 3A, an IP address corresponding to the SIP-URI is obtained and obtained. A packet is sent to the IP address.

  The update information includes, for example, the record retention period and the last update time shown in FIG. 12B, stores the record period registered in the location DB 25, last updated time information, and the like. The

  The server 2 receives the updated password notification from the terminal 3 by the process of step S35 in FIG. Upon receiving the notification, the server 2 updates the password of the priority call management DB 23 shown in FIG. Then, the priority PW management DB 35 of the terminal 3 for which the priority call function “present” is set in the location DB 25 shown in FIG. 12B is synchronized with the priority call management DB 23 of the server 2.

  FIG. 13 and FIG. 14 are sequence diagrams for database synchronization processing between the terminal 3 and the server 2. FIG. 13 is a sequence diagram of synchronization processing in a normal state, and FIG. 14 is a sequence diagram of synchronization processing in the high priority mode. Here, “normal time” indicates that a packet is transmitted without setting high priority.

With reference to FIG. 13, the procedure of the synchronization process will be described. In the normal synchronization process, a high priority setting is not performed for packets transmitted and received between the server 2 and each terminal 3.
First, a handshake (SYN, SYN + ACK, ACK) is performed between the server 2 and each of the terminals 3A, 3B,..., 3N (S121 to S123). After the handshake, the server 2 transmits the difference data of the priority call management DB 23 to each terminal 3 (3A,..., 3N) (S124). The difference data here includes a management number and a tag ID corresponding to the password in addition to the newly set password. The tag ID and password are encrypted and transmitted in order to increase confidentiality.

  Upon receiving the difference data, the terminals 3A,..., 3N return ACK to the server 2 (S125). Then, the changed content is transmitted to the server 2 (S126). The information transmitted to the server 2 includes a corresponding management number and tag ID in addition to the changed password. Of the change confirmation data, the tag ID and password are encrypted and transmitted as in the case of difference data. The server 2 returns an ACK to each of the terminals 3A,..., 3N that transmitted the change confirmation data (S127).

  Each terminal 3A,..., 3N that has received the ACK for the transmission of the change confirmation data transmits FIN to the server 2 in order to end the communication for the synchronization process (S128). The server 2 returns an ACK to the received FIN (S129), and sends the FIN to each of the terminals 3 that sent the FIN (S130). The terminal 3 returns an ACK for the FIN to the server 2 (S131) and ends the process.

  For example, when the packet sent from the server 2 or the terminals 3A,..., 3N does not reach the receiving device due to network degeneration, etc., and the normal synchronization process shown in FIG. The process shown in (5) is repeated a predetermined number of times. Further, if the synchronization is not completed even after repeating the normal synchronization process a predetermined number of times, the server 2 shifts to the synchronization process in the high priority mode shown in FIG.

  In the synchronization processing in the high priority mode shown in FIG. 14, high priority is set for packets transmitted and received between the server 2 and each terminal 3. Specifically, the LAN interface unit 21 sets “101110” as the DSCP value of the IP header, and sets the URG (urgent) flag to ON (sets “1”) among the code bits of the TCP header.

  Each terminal 3 that has received SYN in which the above-described values are set in the DSCP value and the URG flag recognizes that it is a synchronization process in the high priority mode. In the subsequent sequence, until the synchronization process is completed, the terminal 3 and the server 2 set a value indicating high priority in the DSCP value of the IP header portion in the LAN interface unit 39, and set the packet with the URG flag set to ON. Send and receive. The synchronization processing procedure in the high priority mode is the same as the normal synchronization processing shown in FIG. 13, as shown in FIG. 14. Steps S141 to S151 in FIG. 14 are steps S121 to S131 in FIG. And corresponding.

  In the above description, the case where a preset password is changed has been described. The initial password registration may be performed in the same manner. Alternatively, at the time of initial registration, the terminal 3A,..., 3N that has accepted the password input operation notifies the server 2 using means other than the above means, and the server 2 notifies each terminal 3A,. It is good. Furthermore, it is good also as a structure which makes initial registration directly to the server 2, and notifies each terminal 3A ...... 3N.

  Further, the above method is also an example of the method for synchronizing, and is not limited to this. For example, various means such as using a basic SIP function can be used.

  Packets transmitted / received between the server 2 and the terminals 3A,..., 3N for password synchronization processing are transmitted with high priority, so that the packet is transmitted more reliably than when packets are transmitted without setting high priority. Synchronous processing can be performed.

  By the way, the VoIP terminal 3 needs to periodically transmit a registration request (REGISTER message) to the SIP server 2 to make the server recognize the existence of the own device. Hereinafter, the registration process will be described.

  15 and 16 are sequence diagrams for the registration process of the terminal 3. FIG. 15 is a sequence diagram of registration processing in a normal state, and FIG. 16 is a sequence diagram of registration processing in the high priority mode. As in the case of the synchronization processing described with reference to FIGS. 13 and 14, “normal time” here means that a packet is transmitted without setting high priority.

  With reference to FIG. 15, the procedure of the registration process will be described. The registration process shown in FIG. 15 is executed when the terminal 3 performs initial registration with the server 2 or when updating periodically after the initial registration. Here, registration of the originating terminal 3 (terminal 3A in FIG. 5) will be described as an example.

Similar to the synchronization processing shown in FIG. 13, in a normal time, a high priority setting is not particularly performed for a packet transmitted and received between the server 2 and the terminal 3.
First, the terminal 3 transmits a registration request (REGISTER) to the server 2 (S161). When receiving the registration request, the server 2 returns 200 OK and ACK to the terminal 3 (S162, S163). After transmitting the ACK, the server 2 registers necessary information in the location DB 25 shown in FIG. 12B based on the information included in the received registration request, and also waits for a message indicating that it has a priority call function. Set.

  Upon receiving 200 OK and ACK from the server 2, if the terminal 3 is a VoIP terminal having a priority call function, the terminal 3 transmits a message to that effect to the server 2 (S164). The server 2 uses the setting timer for waiting for a message indicating that it has the above priority call function to transmit a message indicating that it has the priority call function within a predetermined period after transmitting an ACK for the registration process. Whether or not to receive from. If the message indicating that the priority call function is provided is not received from the terminal 3 within the period set by the timer for waiting for the message indicating that the priority call function is provided, the terminal 3 is a terminal that does not have the priority call function. Judge that there is. In this case, a value “0” indicating that the priority call function is “none” is set in the location DB 25, and the registration process is terminated. When the message indicating that the priority call function is provided is received within the period set by the timer for waiting for the message indicating that the priority call function is provided, the location DB 25 determines whether the priority call function of the terminal 3 is present or not. A value “1” indicating that “call function is present” is set. Then, an ACK for the message is returned to the terminal 3 (S165), and the registration process is terminated.

Thereafter, the server 2 holds the information registered in the location DB 25 until the next registration update timing. In a normal time, the registration update process is executed every minute, for example.
As a premise that the registration process in the high priority mode shown in FIG. 16 is executed, for example, the registration process in the normal state shown in FIG. It is mentioned that it is not finished. If the registration process has not ended normally, the terminal 3 retransmits the registration request at predetermined time intervals.

  If the registration process is not completed even if the registration request is retransmitted a predetermined number of times because there is no response from the server 2 ((*) in FIG. 16), the terminal 3 shifts to the high priority mode. . In the high priority mode, the terminal 3 sets a value indicating priority registration, that is, priority registration identification information, in a registration request message to be transmitted. Then, the server 2 is transmitted with high priority, that is, the DSCP value is set to EF (= 101110) (S171). As a setting method of the priority registration identification information, for example, the Expires value included in the message header of the REGISTER message is set to a value (“1” in the present embodiment) that is not normally possible.

  Since the registration request packet transferred with high priority is less likely to be discarded by the relay device on the network than the packet without high priority set, the probability of reaching the server 2 is high. In the server 2, when the Expires value of the received registration request is set to “1”, it is recognized as priority registration, and the response (200 OK and ACK) to the terminal 3 is The DSCP value is set to EF (= 101110) and transmitted (S172, S173).

  The server 2 registers necessary information in the location DB 25 shown in FIG. 12B according to the registration request transferred from the terminal 3 with high priority. When this registration is performed, the Expires value included in the message header of the REGISTER message is normally used as the retention time of the location DB 25. In the case of priority registration, a “timer for waiting for a message indicating that a priority call function is provided” After provisional registration with “value” and before the above-mentioned timer expires, when a priority call function compatible message and its response are sent and received between the terminal 3 and the server 2 (S174, S175), The main registration is performed using the value of the “time preferential registration timer” as the holding time of the location DB 25. In the priority registration mode, these messages and responses are also sent and received with high priority, and the presence / absence of the priority call function is registered in the location DB 25.

  As for the value of the “priority registration timer for emergency”, it is desirable to set a time longer than the holding time of the location DB 25 in the normal time. That is, as an example of the case where registration processing in the high priority mode is necessary, there is network degeneration or the like. In such a case, when the terminal 3 transmits a registration request at a time interval similar to that in the normal time, the load on the network increases.

  Therefore, in order to reduce the load on the network by the registration process, the timer value is set larger than the normal time. The server 2 continues to hold information preferentially registered in the location DB 25 during the period when the emergency priority registration timer is set. The terminal 3 starts processing for the next registration update after a period longer than the normal time according to the set period of the emergency priority registration timer. As a result, the load on the network is reduced by the packets sent from the terminal 3 and the server 2 to the network for the registration process.

  When registration in the high priority mode is completed and update registration is performed next, normal registration processing is performed. In such update registration after registration in the high priority mode, for example, when a period of two thirds of the emergency priority registration timer has elapsed, the terminal 3 transmits a registration request in normal times. I will do it. When two-thirds of the emergency priority registration timer has elapsed, the server 2 receives a registration request that is not set with high priority, and the normal registration sequence shown in FIG. 15 ends normally. In such a case, the normal registration process is restored. If the registration process cannot be completed normally, the registration process in the high priority mode is performed again, and the emergency priority registration timer is restarted.

  FIG. 17 is a flowchart showing registration processing in the server 2. The process shown in FIG. 17 is executed in the SIP basic function unit such as the location DB management unit 26 and the register unit 27 of the server 2 in FIG. If the server 2 determines in step S16 in FIG. 8 that the server 2 has received the SIP packet for the registration request, the server 2 executes the process shown in FIG.

  First, in step S41, reception of a registration request (REGISTER) from the terminal 3 is recognized. In step S42, based on the value of Expires in the message header that can be read by the server 2 in the received packet, it is determined whether the registration is in the normal time or in the high priority mode.

If Expires is not 1 in step S42, that is, if it is determined that registration is normal, the process proceeds to step S43, and the server 2 returns 200 OK and ACK to the terminal 3. Here, no priority is set for 200 OK and ACK. In step S44, necessary information is registered in the location DB 25. In step S45, a timer for waiting for a message indicating that the terminal 3 has a priority call function is set, and a message waiting state is entered. The presence / absence of the priority call function is registered in the location DB 25 according to whether or not the message is received within the period set by the timer. And it progresses to step S46, ACK with respect to a message is returned to the terminal 3, and a process is complete | finished.
On the other hand, if it is determined in step S42 that Expires is 1, that is, registration in the high priority mode, the process proceeds to step S47.

  In step S47, 200 OK and ACK are transmitted to the terminal 3 with high priority, and in step S48, after provisional registration in the location DB 25 using a timer value for waiting for a message indicating that the terminal 3 has a priority call function. , Enters the waiting state for the priority call function compatible message. If a priority call function compatible message is received, the process proceeds to step S50, an ACK for the message is returned to the terminal 3 with high priority, and the process proceeds to step S51. In step S51, the main registration is performed in the location DB 25 using the “emergency priority registration timer”. When the main registration is completed, the registration process in the high priority mode is terminated.

  If it is determined in step S49 that the priority call function compatible message has not been received, it is determined that the normal terminal that does not have the priority call function has actually registered the value of Expires as 1, and in S48, the location DB 25 The provisional registration contents are discarded and the registration process is terminated.

Here, in the “emergency priority registration timer”, a waiting period longer than the Expires value included in the message header of the normal REGISTER message is set.
Thus, for the registration process of the terminal 3, by transferring the packet transmitted and received between the server 2 and the terminal 3 with high priority, compared with the case where the packet is transferred without particularly setting high priority. The registration process can be performed reliably.

Finally, priority call exclusive processing will be described.
As described above, in the IP telephone system 1 according to the present embodiment, the priority call can be performed by either recognizing the RFID tag or directly inputting the password into the terminal 3. For this reason, for example, when a priority caller performs a priority call using an RFID tag, a third party inputs a password corresponding to the RFID tag to another terminal 3 to make a priority call. It can also happen. In such a case, the server 2 refers to the priority call management DB 23 and notifies the user who later tried to place a priority call that the priority calls overlap, and rejects the connection.

  18 and 19 are diagrams for explaining a call exclusion process. First, FIG. 18 shows a case where a certain priority caller causes the terminal 3A to recognize the RFID tag and makes a priority call to the terminal 3B. The procedure for establishing the priority call is as described above with reference to FIG.

  The server 2 determines that the call is in progress until receiving the 200 OK message for BYE and BYE after receiving INVITE of the priority call for the terminal 3A. During this time, in the priority call management DB 23 of the server 2, for “tag ID: usr001”, the session state holds a value indicating that a call is in progress.

  In FIG. 19, while the terminal 3A and the terminal 3B are talking, another caller uses the password “# 001” set for the “tag ID: usr001” to the terminal 3D. Shows a case where an attempt is made to make a priority call.

  The server 2 refers to the priority call management DB 23 and determines whether or not the session state corresponding to the input password (or tag ID) is “no call”. In the example shown in FIG. 19, the session state corresponding to the password “# 001” is “busy” due to the priority call of the terminal 3A. For this reason, even if the correct password “# 001” is input for “tag ID: usr001”, it is determined that the call is a duplicate priority call, the terminal 3C is notified, and the priority call is not permitted. .

  By the way, the VoIP terminal 3 in FIG. 2 and the SIP server 2 in FIG. 3 can be configured by using an information processing apparatus (computer) as shown in FIG. 20, for example. 20 includes a CPU (central processing unit) 1001, a memory 1002, an input device 1003, an output device 1004, an external storage device 1005, a medium drive device 1006, and a network connection device 1007, which are connected to each other via a bus 1008. It is connected.

  The memory 1002 includes, for example, a read only memory (ROM), a random access memory (RAM), and the like, and stores programs and data used for processing. The CPU 1001 performs necessary processing by executing a program using the memory 1002.

  The control processing unit 38 in FIG. 2, the priority call determination unit 22 in FIG. 3, the priority password (PW) management database (DB) management unit 24, the location database (DB) management unit 26, and the SIP basic function unit are stored in the memory 1002. It corresponds to the function realized by executing the programmed program.

  The input device 1003 is, for example, a keyboard, a pointing device, a touch panel, or the like, and is used for inputting an instruction or information from a user such as a priority caller. The output device 1004 is, for example, a display, a printer, a speaker, or the like, and is used for outputting a question alarm or a processing result to the user side.

  The external storage device 1005 is, for example, a magnetic disk device, an optical disk device, a magneto-optical disk device, a tape device, or the like. The information processing apparatus stores the program and data in the external storage device 1005 and loads them into the memory 1002 for use as necessary.

  The medium driving device 1006 drives a portable recording medium 1009 and accesses the recorded contents. The portable recording medium 1009 is an arbitrary computer-readable recording medium such as a memory card, a flexible disk, a CD-ROM (compact disk read only memory), an optical disk, and a magneto-optical disk. The user stores the program and data in the portable recording medium 1009 and loads them into the memory 1002 for use as necessary.

  The network connection device 1007 is connected to an arbitrary communication network such as a local area network (LAN) or the Internet, and performs data conversion accompanying communication. The information processing apparatus receives the program and data from an external apparatus via the network connection apparatus 1007 as necessary, and loads them into the memory 1002 for use.

  FIG. 21 shows a computer-readable recording medium that can supply a program and data to the information processing apparatus of FIG. Programs and data stored in the portable recording medium 1009 and the database 1103 of the server 1101 are loaded into the memory 1002 of the information processing apparatus 1102. The server 1101 generates a carrier signal for carrying the program and data, and transmits the carrier signal to the information processing apparatus 1102 via an arbitrary transmission medium on the network. The CPU 1001 executes the program using the data and performs necessary processing.

  As described above, according to the IP telephone system 1 according to the present embodiment, when a priority caller tries to make an IP phone call, the VoIP terminal 3 detects trigger information input by the priority caller. To do. When the trigger information input by the operation of the priority caller is detected, priority call identification information indicating that the call is a priority call by the priority caller is set in a packet for establishing a session and transmitted with high priority. As described above, the VoIP terminal 3 directly identifies the information input by the operation of a specific caller who is permitted to make a priority call, that is, the trigger information for the priority call. It becomes possible to change dynamically according to the needs of the user of the terminal 3. Only when a specific caller (priority caller) performs an operation, the trigger information is recognized and a high-priority packet is transmitted. It is possible to carry out while maintaining the priority state. In other words, it becomes possible for a priority caller who is allowed to make a priority call to make a high-quality priority call for an arbitrary call destination in the IP telephone system 1 more reliably.

  In addition, the VoIP terminal 3 and the server 2 refer to information set in a predetermined field of the received packet, recognize that the packet is related to the priority call, and transfer or receive the packet with high priority. Responds to packets. Since it is determined that the call is a priority call and packets related to session establishment are transmitted and received with high priority, it is possible to establish the priority call more reliably even when the network is degraded.

Regarding the above embodiment, the following additional notes are disclosed.
(Appendix 1)
A communication system that includes a terminal device and a server device that processes a request from the terminal device, and transmits and receives data between a plurality of terminal devices via a network,
The terminal device
When detecting trigger information related to the start of priority communication, setting means for setting priority communication identification information indicating priority communication in a packet indicating a session establishment request with another terminal device;
The packet indicating the session establishment request in which the priority communication identification information is set by the setting unit may be in a congestion state in the relay device that exists between the terminal device and the server device on the network. A transmission means for transmitting with control information such that the discard probability is low;
With
The server device
When receiving the session establishment request from the terminal device, determination means for determining whether or not the priority communication identification information is included in the session establishment request;
In the relay device existing between the server device and the terminal device on the network, a packet indicating the session establishment request determined by the determining means to include the priority communication identification information is congested. Even with the control information that lowers the probability of destruction, sending means for sending to the terminal device that is the transmission destination included in the session establishment request,
In the determination means, storage means for storing information for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions;
A communication system comprising:
(Appendix 2)
A terminal device that transmits and receives data to and from other terminal devices via a network,
When detecting trigger information related to the start of priority communication, setting means for setting priority communication identification information indicating priority communication in a packet indicating a session establishment request with the other terminal device;
With respect to a packet indicating a session establishment request in which the priority communication identification information is set by the setting means, the discard probability is lowered even in a congested state in the relay device existing between the server device and the network. Transmitting means for transmitting with the control information,
A terminal device comprising:
(Appendix 3)
It is determined whether or not the priority communication identification information is included in a session establishment request received from a terminal device other than its own device, and if it is determined that the priority communication identification information is included, based on the session establishment request Information for distinguishing a series of sessions to be started from other sessions is read from the session establishment request and stored in the storage device, and the transmission means responds to the session establishment request in response to the session establishment request. The terminal device according to appendix 2, characterized in that information for identification is set, and the control information is transmitted.
(Appendix 4)
The terminal device according to appendix 2, wherein the trigger information includes information indicating that the operation of the terminal device is performed by a priority communicator permitted to perform priority communication.
(Appendix 5)
Dialog identification information for identifying a dialog between the own device and the other terminal device of the communication partner is used as information for identifying a series of sessions started based on the session establishment request from other sessions. The terminal device according to Supplementary Note 2, which is characterized.
(Appendix 6)
There is a server device that processes a request from a terminal device that transmits and receives data via a network,
When receiving a session establishment request from a terminal device, a determination unit that determines whether or not priority communication identification information indicating priority communication is included in the session establishment request;
Even if the packet indicating the session establishment request determined to include the priority communication identification information in the determination unit is in a congestion state in the relay device existing between the terminal device and the network. Sending means for sending control information such that the discard probability is low, and sending it to the terminal device that is the destination included in the session establishment request;
In the determination means, storage means for storing information for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions;
A server device comprising:
(Appendix 7)
A program for operating a computer as a terminal device that transmits and receives data to and from another terminal device via a network,
When trigger information related to the start of priority communication is detected, priority communication identification information indicating priority communication is set in a packet indicating a session establishment request with another terminal device,
The packet indicating the session establishment request in which the priority communication identification information is set has a low discard probability even in the congestion state in the relay device existing between the terminal device and the server device on the network. Send with control information like
A program that causes a computer to execute processing.
(Appendix 8)
Determine whether the priority communication identification information is included in the session establishment request received from a terminal device other than its own device,
When it is determined that the priority communication identification information is included, information for identifying a series of sessions started based on the session establishment request from other sessions is read from the session establishment request and stored in the storage device And setting information for distinguishing the session from other sessions in a response to the session establishment request, and transmitting the control information.
The program according to appendix 7, further causing the computer to execute processing.
(Appendix 9)
The program according to claim 7, wherein the trigger information includes information indicating that the terminal device is operated by a priority communicator permitted to perform priority communication.
(Appendix 10)
Dialog identification information for identifying a dialog between the own device and the other terminal device of the communication partner is used as information for identifying a series of sessions started based on the session establishment request from other sessions. The program according to appendix 7, which is characterized.
(Appendix 11)
When it is detected that authentication information for authenticating a priority communicator permitted for priority communication is newly input, the authentication information and the priority communication identification information associated with the authentication information are displayed on the server device. Notify
When there is a synchronization instruction from the server device, the computer further executes a process of storing the priority communication identification information and the newly input authentication information in association with each other in accordance with the instruction. ,
When the control information is attached to the synchronization instruction received from the server device within a predetermined period, the control information is transmitted to the server device with respect to the packet related to the synchronization processing. The program according to appendix 7, characterized by:
(Appendix 12)
In response to a registration request transmitted without the control information, if a response from the server device is not received within a predetermined period, a value indicating that the waiting period has expired is set in the packet related to the registration request And send it with the control information,
When the registration process is completed based on the registration request transmitted with the control information set with the value indicating the waiting period expired, the registration process is completed based on the registration request without the control information. If you send a registration request that does not set a priority after a period longer than the period until the next registration request is sent,
When the registration process cannot be completed based on the registration request without the control information, the computer further causes the computer to execute a process of continuing to transmit the registration request in which a value indicating that the waiting period has expired is set. The program according to appendix 7.
(Appendix 13)
A program for operating a computer as a server device that processes a request from a terminal device that transmits and receives data via a network,
When receiving a session establishment request from the terminal device, it is determined whether or not priority communication identification information indicating priority communication is included in the session establishment request,
When it is determined that the priority communication identification information is included, a control for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions Information is read out from the session establishment request and stored, and a packet indicating the session establishment request is stored on the network between the terminal device and the server device even in a congestion state. A program characterized by causing a computer to execute a process of attaching control information so as to reduce the probability of discarding and sending it to a terminal device as a transmission destination included in the session establishment request.
(Appendix 14)
When authentication information for authenticating a priority communicator permitted for priority communication is notified from the terminal device, the notified authentication information is associated with the priority communication identification information and stored in a storage unit. ,
Causing the computer to further execute a process of sending an instruction for synchronizing the storage means and the storage means of the terminal device and the other terminal device to the terminal device and the other terminal device;
If the synchronization processing is not completed within a predetermined period, a packet related to the synchronization instruction to the terminal device and other terminal devices is sent with the control information. The listed program.
(Appendix 15)
If the registration request received from the terminal device is set to a value indicating that the waiting period has expired, a response to the registration request to be sent to the terminal device is sent with the control information,
Next, a waiting period until the registration request is received is set longer than the waiting period when the registration request without the control information is processed,
When the registration request without the control information is received from the terminal device within the set period and the registration process based on the registration request is completed, the control information is added as the waiting period. 14. The program according to appendix 13, wherein the program further causes the computer to execute a process of changing to a value when an unregistered request is processed.
(Appendix 16)
2. The communication system according to claim 1, wherein the control information attached to the packet by the transmission means of the terminal device and the sending means of the server device set an EF value as control information attached to the packet.

1 IP telephone system 2 SIP server (server)
3 VoIP terminal (terminal)
21 LAN interface unit 22 Priority call determination unit 23 Priority call management database (DB)
24 Priority Password (PW) Management Database (DB) Management Unit 25 Location Database (DB)
26 location database (DB) management unit 27 register unit 28 proxy unit 29 redirect unit 30 authentication unit 31 RFID reception unit 32 on-hook / off-hook detection unit 33 operation unit 34 display display unit 35 priority password (PW) management database (DB)
36 Handset unit 37 Audio codec unit 38 Control processing unit 39 LAN interface unit

Claims (8)

A communication system that includes a terminal device and a server device that processes a request from the terminal device, and transmits and receives data between a plurality of terminal devices via a network,
The terminal device
When detecting trigger information related to the start of priority communication, setting means for setting priority communication identification information indicating priority communication in a packet indicating a session establishment request with another terminal device;
The packet indicating the session establishment request in which the priority communication identification information is set by the setting unit may be in a congestion state in the relay device that exists between the terminal device and the server device on the network. A transmission means for transmitting with control information such that the discard probability is low;
With
The server device
When receiving the session establishment request from the terminal device, determination means for determining whether or not the priority communication identification information is included in the session establishment request;
In the relay device existing between the server device and the terminal device on the network, a packet indicating the session establishment request determined by the determining means to include the priority communication identification information is congested. Even with the control information that lowers the probability of destruction, sending means for sending to the terminal device that is the transmission destination included in the session establishment request,
In the determination means, storage means for storing information for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions;
A communication system comprising: A terminal device that transmits and receives data to and from other terminal devices via a network,
When detecting trigger information related to the start of priority communication, setting means for setting priority communication identification information indicating priority communication in a packet indicating a session establishment request with the other terminal device;
With respect to a packet indicating a session establishment request in which the priority communication identification information is set by the setting means, the discard probability is lowered even in a congested state in the relay device existing between the server device and the network. Transmitting means for transmitting with the control information,
A terminal device comprising: It is determined whether or not the priority communication identification information is included in a session establishment request received from a terminal device other than its own device, and if it is determined that the priority communication identification information is included, based on the session establishment request Information for distinguishing a series of sessions to be started from other sessions is read from the session establishment request and stored in the storage device, and the transmission means responds to the session establishment request in response to the session establishment request. The terminal device according to claim 2, wherein information for identification is set, and the control information is attached and transmitted. The terminal device according to claim 2, wherein the trigger information includes information indicating that the operation of the terminal device is performed by a priority communication person permitted to perform priority communication. Dialog identification information for identifying a dialog between the own device and the other terminal device of the communication partner is used as information for identifying a series of sessions started based on the session establishment request from other sessions. The terminal device according to claim 2, wherein: There is a server device that processes a request from a terminal device that transmits and receives data via a network,
When receiving a session establishment request from a terminal device, a determination unit that determines whether or not priority communication identification information indicating priority communication is included in the session establishment request;
Even if the packet indicating the session establishment request determined to include the priority communication identification information in the determination unit is in a congestion state in the relay device existing between the terminal device and the network. Sending means for sending control information such that the discard probability is low, and sending it to the terminal device that is the destination included in the session establishment request;
In the determination means, storage means for storing information for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions;
A server device comprising: A program for operating a computer as a terminal device that transmits and receives data to and from another terminal device via a network,
When trigger information related to the start of priority communication is detected, priority communication identification information indicating priority communication is set in a packet indicating a session establishment request with another terminal device,
The packet indicating the session establishment request in which the priority communication identification information is set has a low discard probability even in the congestion state in the relay device existing between the terminal device and the server device on the network. Send with control information like
A program that causes a computer to execute processing. A program for operating a computer as a server device that processes a request from a terminal device that transmits and receives data via a network,
When receiving a session establishment request from the terminal device, it is determined whether or not priority communication identification information indicating priority communication is included in the session establishment request,
When it is determined that the priority communication identification information is included, information for identifying a series of sessions started based on the session establishment request determined to include the priority communication identification information from other sessions Is stored from the session establishment request, and a packet indicating the session establishment request is discarded on the network in the relay device between the terminal device and the server device even in a congestion state. A program characterized by causing a computer to execute a process of attaching control information with a low probability and sending it to a terminal device that is a transmission destination included in the session establishment request.