JP2014116911A - Information processing device, control method therefor, program and image processing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mechanism for appropriately selecting SDP medium information for each SIP communication transport protocol even if SDP medium information is not designated at the transmission/reception of an INVITE command.SOLUTION: If SDP is not included in an INVITE request received from an SIP server, an information processing device determines an SIP communication transport protocol. On determination that the transport protocol is UDP, the information processing device selects SDP medium information according to the type of the SIP server. On determination that the transport protocol is TCP or SSL, the information processing device selects all of the SDP medium information, and generates an INVITE response having the selected SDP medium information set therein, to respond to the SIP server.

Description

  The present invention relates to an information processing apparatus that performs SIP communication, a control method thereof, a program, and an image processing apparatus.

  In recent years, using the IP network, SIP (Session Initiation Protocol) and T.I. An IP facsimile communication environment conforming to H.38 is becoming widespread (for example, Patent Document 1). In addition, the provision of a network for the purpose of providing a telephone / video communication service called NGN has been started. In SIP communication, when a SIP request (INVITE) is received, it is necessary to check whether SDP (Session Description Protocol) is specified in the received INVITE, and when it is not included, it is necessary to set SDP in the response. In addition, in SIP communication, media information of SDP that allows communication by a communication device is limited. Therefore, it is necessary to include an appropriate value according to the communication device. For example, an SIP server in an NGN environment must include an SDP of “media type: application, transport: TCP”. On the other hand, some other SIP servers need to include an SDP “media type: audio, transport: RTP / AVP” (for example, CISCO).

JP 2005-086724 A

  However, the above prior art has the following problems. If the SDP as described above is not included, communication fails. However, there is a problem that a communication device does not know what communication device the SIP server with which it communicates is.

  As a method for avoiding this problem, there is a method of fixing SDP media by limiting the number of devices to communicate to one. However, in this method, it is necessary to limit the number of devices to communicate with each other, and a user who wants to communicate with a plurality of devices needs to distinguish and use a plurality of devices corresponding to each SIP server, which is inconvenient. .

  As another avoidance method, there is a method of communicating by including a plurality of media information in the SDP. Thereby, even if the information of the communication partner is not known, communication is successful if the appropriate media information preferred by the communication device is included. For example, an SDP including both “media type: application, transport: TCP”, which is essential for a SIP server in an NGN environment, and “media type: audio, transport: RTP / AVP”, which is mandatory for another SIP server. It is a technique to transmit. However, when SIP communication is performed by UDP, if a plurality of media information is included in the SDP, there is a possibility that the upper limit of the MTU size (generally about 1492 bytes) of the UDP packet may be reached. If the upper limit of the MTU size is exceeded, problems such as being discarded on the IP route or being unable to be processed correctly by the receiver due to packet fragmentation occur.

  The present invention has been made in view of the above-described problem. Even when the SDP media information is not specified when the INVITE command is transmitted / received, the SDP is preferably used for each transport protocol of SIP communication. The purpose is to provide a mechanism for selecting media information.

  The present invention is an information processing apparatus that performs SIP communication, a receiving unit that receives an INVITE request from a SIP server, and an analyzing unit that analyzes whether or not the INVITE request received by the receiving unit includes an SDP. When the analyzing means analyzes that the SDP is not included in the INVITE request, the protocol determining means for determining a transport protocol of SIP communication and the transport protocol is UDP by the protocol determining means If determined, the SDP media information is selected according to the type of the SIP server, and if the transport protocol is determined to be TCP or SSL by the protocol determination means, all the SDP media information is selected. Selecting means for And generates an INVITE response which sets the media information of the selected SDP by-option means, characterized in that it comprises a response means responsive to said SIP server.

  In addition, the present invention is an information processing apparatus that performs SIP communication, and transmits an INVITE request to a SIP server, a protocol determination unit that determines a transport protocol of SIP communication, and the transport by the protocol determination unit When it is determined that the protocol is UDP, SDP media information is selected according to the type of the SIP server. When the protocol determination unit determines that the transport protocol is TCP or SSL, all The apparatus comprises: selection means for selecting SDP media information; and transmission means for generating an INVITE request in which the SDP media information selected by the selection means is set and transmitting the request to the SIP server.

  The present invention can be realized as an image processing apparatus including any one of the information processing apparatuses described above and an image processing unit that processes an image.

  The present invention can provide a mechanism for suitably selecting SDP media information for each transport protocol of SIP communication even when SDP media information is not designated when sending and receiving an INVITE command.

The block diagram which shows the system configuration | structure of the communication terminal device which concerns on this embodiment. The figure of the network where the communication terminal device concerning this embodiment is connected. The flowchart when the communication terminal device which concerns on this embodiment receives an INVITE request. The flowchart when the communication terminal device which concerns on this embodiment receives the INVITE request without OfferSDP by UDP communication. The other flowchart when the communication terminal device which concerns on this embodiment receives the INVITE request without OfferSDP by UDP communication. The figure which shows an example of the SIP server setting screen in the communication terminal device which concerns on this embodiment. The figure which shows an example of the SIP server default classification setting screen in the communication terminal device which concerns on this embodiment. The figure which shows an example of the communication history in the communication terminal device which concerns on this embodiment. The figure which shows an example of the INVITE request | requirement without OfferSPD. The flowchart in case the communication terminal device which concerns on this embodiment transmits an INVITE request.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. The following embodiments do not limit the invention according to the claims, and all combinations of features described in the embodiments are not necessarily essential to the solution means of the invention.

<Configuration of information processing apparatus>
Hereinafter, the best mode for carrying out the present invention will be described with reference to FIGS. 1 to 10. First, a configuration example of a communication terminal apparatus that is an information processing apparatus (image processing apparatus) according to the present embodiment will be described with reference to FIG.

  The communication terminal device 100 includes a CPU 101, a display / operation unit 102, a reading unit 103, a recording unit 104, an image processing unit 105, an image storage unit 106, a RAM 107, a call destination information storage unit 108, a selected network setting storage unit 109, Callee information analysis unit 110, calling network discrimination unit 111, T.P. 38 control unit 112, SIP call control unit 113, G3 FAX transmission control unit 114, G3 FAX call control unit 115, and IP control unit 116. A central processing unit (CPU) 101 performs overall control of the entire apparatus by executing a control program. The RAM 107 stores system data and various information used by the control program. The display / operation unit 102 is configured with a touch panel or the like, and performs various operations (calling operation or the like) for operating the communication terminal apparatus 100 by the user or displays various information.

  The reading unit 103 reads a transmission original or a copy original and outputs image data. The recording unit 104 records the received image data and the read image data on a recording sheet and outputs them. The image processing unit 105 performs processing such as encoding, decoding, enlargement, and reduction for image data. The image storage unit 106 stores received image data or read image data. Thus, since the communication terminal device 100 has various image processing functions, it can also be applied as an image processing device.

  The call destination information storage unit 108 stores call destination information registered by the user through key operations on the display / operation unit 102. The selected network setting storage unit 109 stores information such as a network for calling a facsimile (via a SIP server, via a T.38 gateway, via a home gateway). The call destination information analysis unit 110 analyzes the call destination information of the partner communication terminal device input from the display / operation unit 102 when making a call. The calling network discrimination unit 111 uses the analyzed call destination information based on the analysis result of the call destination information in the call destination information analysis unit 110 to store the call destination stored in the selected network setting storage unit 109. By referring to the setting information, the network from which the facsimile is called is determined.

  T. T. et al. 38. The transmission control unit 112 is an ITU-T recommendation T.38. The real-time communication protocol is controlled according to 38 procedures. The SIP call control unit 113 controls the establishment, maintenance, and termination of a call in the real-time Internet fax T38 using procedures defined in RFC 3261 (SIP) and RFC 2327 (SDP) of IETF. The IP control unit 116 is connected to the IP network 204 and performs communication control for starting and transmitting various data by starting the Internet. The G3 FAX transmission control unit 114 is an ITU-T recommendation T.264. The facsimile protocol is controlled according to 30 procedures. The G3 FAX call control unit 115 performs call establishment and network connection control on the analog public line network 206 under the transmission control of the G3 FAX transmission control unit 114.

  The communication terminal device 100 is further provided with a system bus 117 for exchanging data between the above-described units. Communication terminal apparatus 100 is connected to IP network 204 by IP control unit 116 and is communicably connected to a partner communication terminal apparatus via IP network (LAN) 204. Further, the G3 FAX call control unit 115 is connected to the public line network 206, and is connected to the partner communication terminal device via the public line network 206 so as to be communicable.

<Network configuration example>
Next, a configuration example of a network to which the communication terminal device 100 according to the present embodiment is connected will be described with reference to FIG. Communication terminal apparatus 100 is connected to LAN 204. The LAN 204 is connected to the NGN network 205 via the home gateway 203. The home gateway 203 also serves as a proxy for the SIP server 202 in the NGN environment. The LAN 204 includes a LAN SIP server 201 and an NGN SIP server 202. Further, as shown in FIG. 2, the home gateway 210 is connected to the NGN network 205. Furthermore, the home gateway 210 is connected to other communication terminal apparatuses 211 and 212 via another LAN (IP network).

<INVITE command>
Control when the communication terminal apparatus 100 receives an INVITE command, which is a request for starting SIP communication, from these SIP servers 201 and 202 will be described. In an INVITE request / response in SIP (Session Initiation Protocol), it is necessary to include SDP (Session Description Protocol) information indicating a method for performing data communication. The SDP to be transmitted first is called Offer SDP. All the corresponding media information is included in the Offer SDP. On the other hand, a device that has received Offer SDP needs to send Answer SDP. The Answer SDP specifies and responds to the media that is actually communicated from the SDP presented in the Offer SDP.

  Below, with reference to FIG. 3, the detailed process sequence in the communication terminal device 100 is demonstrated. The processing described below is realized by the CPU 101 executing a program stored in a memory such as the RAM 107 of the communication terminal device 100.

  When the INVITE command is received, the CPU 101 analyzes the INVITE command in S100, and determines whether or not the Over SDP information is included in the INVITE command in S101. When Offer SDP information is included in the INVITE, the process proceeds to S103, and the CPU 101 determines (selects) the media information that can be communicated from the media information of the SDP designated by INVITE. Thereafter, in S105, the CPU 101 generates an INVITE response including the determined media information.

  On the other hand, if the Offer SDP information is not included in INVITE, the process proceeds to S102, where the CPU 101 functions as a protocol determination unit and confirms the transport protocol for SIP communication. If the transport protocol for SIP communication is TCP or SSL, the process proceeds to S104, and the CPU 101 sets all media information corresponding to Offer SDP in the INVITE response, and generates an INVITE response in S105.

  On the other hand, when the transport protocol of SIP communication is UDP, the process proceeds to S106, and the CPU 101 determines whether it is possible to specify the type of the SIP server from the INVITE request. If the type can be specified because the SIP server is registered, the process advances to step S108, and the CPU 101 selects and sets the media information to be set in the Offer SDP from the type of the registered SIP server, and sends an INVITE response in step S105. Generate. For example, when the type of the SIP server is NGN, “media type: application, transport: TCP” is selected as the SDP media information. In the case of a LAN, the SDP information is “media type: audio, transport: RTP / AVP”. On the other hand, if the type cannot be specified because the SIP server is not registered, the process advances to step S107, and the CPU 101 sets default media information in the Offer SDP, and generates an INVITE response in step S105.

<SIP server identification method>
Next, a method for specifying the SIP server from the INVITE request in S106 of FIG. 3 will be described in detail with reference to FIG. Note that the processing described below is realized by the CPU 101 executing a program stored in a memory such as the RAM 107 of the communication terminal device 100.

  In S200, the CPU 101 acquires the transmission source IP address of the received INVITE command. Subsequently, in S <b> 201, the CPU 101 confirms whether or not there is a SIP server that matches the transmission source IP address from the list of SIP servers set in the communication terminal device 100. As a result, if a SIP server with the same IP address is registered, it is identified by referring to the type of the registered SIP server, and the process returns to the flowchart of FIG. On the other hand, if no SIP server with the same IP address is registered, the process returns to the flowchart of FIG.

  Here, with reference to FIG. 6, the SIP server list which the communication terminal device 100 has is demonstrated. FIG. 6 is an example of a screen for registering the SIP server type of the display / operation unit 102 of the communication terminal apparatus 100. As the SIP server setting, in addition to the name for identifying the SIP server for communication and the IP address of the SIP server, the SIP server type information is registered and managed. The SIP server type information is an item that is a characteristic of the SIP server. For example, the communication environment managed by the SIP server, or the vendor information of the SIP server. According to this type, media information to be set in Offer SDP is determined (selected).

  As shown in FIG. 6, the IP address and type of the SIP server can be registered and deleted using a registration button 302 and a deletion button 303. Here, as shown in the setting area 301, the SIP server with the IP address of 172.16.1.1 is the SIP server for the NGN environment, and the SIP server of 172.16.1.2 is the SIP server for the LAN environment. It is set to be a server.

  FIG. 7 is an example of a screen for registering the default communication setting of the SIP server of the display / operation unit 102 of the communication terminal device 100. This screen is displayed when, for example, the type column of the setting area 301 in FIG. 6 is selected. In this example, the SIP server type can be registered by selecting either the NGN button 311 or the LAN button 310 as the SIP server type. When set to NGN, the communication terminal apparatus 100 operates as an NGN environment when communicating with a SIP server whose type is unknown. This setting is referred to when the type of the SIP server for communication is unknown as in S107 of FIG.

  When the setting button 312 is pressed while either the NGN button 311 or the LAN button 310 is selected, the selected type is set and the screen returns to the screen of FIG. Returning to the screen of FIG. 6, the type set in the type area of the setting area 301 is displayed. When the return button 313 is pressed, the screen returns to the screen of FIG. 6 without changing the setting.

<Modification>
Next, another method for specifying a SIP server from the INVITE request in S106 will be described with reference to FIG. Here, the type of the SIP server is specified using the past communication history. Note that the processing described below is realized by the CPU 101 executing a program stored in a memory such as the RAM 107 of the communication terminal device 100.

  In S210, the CPU 101 confirms the domain name of the From header of the received INVITE request. When the domain name of the From header is acquired, in S211, the CPU 101, among the history information that has been successfully communicated from the past communication history (history information) stored in a memory such as an HDD provided in the communication terminal device 100, Determine whether there is a history that matches the sender's domain name. As a result, if there is a history of successful communication for the same domain, the media information used in the communication can be used as the SDP, so that it is determined that the type of SIP server can be specified. This is because, in the same domain, there is a high possibility of using the same SIP server when communicating. In addition, although OfferSDP has not been set in INVITE, there is a possibility that other communication terminal devices existing in the same domain are performing communication by setting OfferSDP in the INVITE request. If there is a history of communication with such a communication terminal device in the past, SDP media information necessary for communication with the SIP server can be specified. On the other hand, if there is no history of successful communication with the same domain, it is determined that the SIP server type cannot be specified.

  As a specific example, a case where the INVITE request shown in FIG. 9 is received will be described. From the INVITE request in FIG. 9, the transmission source is iRADV03 @ conon-mj. co. It can be seen that it is jp. In this case, the domain name of the transmission source is “conn-mj.co.jp”.

  A case where the communication history stored in the communication terminal device 100 at this time is FIG. 8 will be described. As shown in FIG. 8, the communication history stores the communication history No, the communication result, the address of the sender, and the communication media information in association with each other. From this communication history, the source domain name is “” conn-mj. co. The history of successful communication with “jp” is No1, No3, and the used media information is “application, tcp.” Therefore, the SDP in response to the INVITE request in FIG. It responds by setting tcp ".

<INVITE request>
Next, a processing procedure when an INVITE request is transmitted will be described with reference to FIG. The present invention can be applied not only when an INVITE request is received but also when an INVITE request is transmitted. Note that the processing described below is realized by the CPU 101 executing a program stored in a memory such as the RAM 107 of the communication terminal device 100.

  In the case of transmitting an INVITE request, in S300, the CPU 101 functions as a protocol determination unit and confirms a transport protocol for performing SIP communication. At this time, if the transport protocol is TCP / SSH, the process proceeds to S301, and the CPU 101 sets all the media information that the communication terminal apparatus 100 is capable of as media information to be included in OfferSDP, and generates an INVITE request in S305. To do.

  On the other hand, when the SIP communication protocol is UDP, the process proceeds to S302, and it is determined whether or not the type of the SIP server as the communication destination can be specified. Based on the determination result, the SDP media information set in S303 or S304 is determined (selected), and an INVITE request is generated in S305. The method for specifying the SIP server type of the communication destination in the case of UDP is the same method as in Patent Document 1.

  As described above, according to the present invention, when an INVITE request that does not include an Offer SDP is received in a communication terminal device that supports various media types as a media type to be set as OfferSDP, The media information of the OfferSDP that responds can be automatically determined (selected). The present invention can also be applied when generating an IVITE request when an INVITE request is transmitted.

<Other examples>
The present invention can also be realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program. It is a process to be executed.

Claims (10)

An information processing apparatus that performs SIP communication,
Receiving means for receiving an INVITE request from the SIP server;
Analyzing means for analyzing whether or not SDP is included in the INVITE request received by the receiving means;
If the analysis means analyzes that the SDP is not included in the INVITE request, a protocol determination means for determining a transport protocol for SIP communication;
When the protocol determination unit determines that the transport protocol is UDP, SDP media information is selected according to the type of the SIP server, and the transport protocol is TCP or SSL by the protocol determination unit. A selection means for selecting media information of all SDPs,
An information processing apparatus comprising: response means for generating an INVITE response in which the media information of the SDP selected by the selection means is set and responding to the SIP server. Further comprising storage means for storing information of a SIP server capable of communicating with the information processing apparatus;
The selection means includes
If it is determined by the protocol determination means that the transport protocol is UDP, whether or not the source IP address included in the INVITE request matches any of the SIP servers stored in the storage means Means for determining
If there is information of the SIP server with the same source IP address in the storage means, the media information of the SDP is selected according to the type of the SIP server stored in the storage means,
2. The information processing apparatus according to claim 1, wherein if there is no information on the SIP server having the same source IP address in the storage unit, media information of a predetermined SDP is selected. A storage unit for storing SIP communication history information;
The selection means includes
When the protocol determination unit determines that the transport protocol is UDP, the domain name of the From header included in the INVITE request is the same domain name in the communication history stored in the storage unit. Means for determining whether there is a history of successful communication;
If there is a history of successful communication, select the media information of the history stored in the storage means as the media information of the SDP,
2. The information processing apparatus according to claim 1, wherein if there is no history of successful communication, media information of a predetermined SDP is selected.   The information processing apparatus according to claim 2, further comprising a setting unit that sets the media information of the predetermined SDP. The selection means includes
4. The media information of the SDP included in the INVITE request is selected when the analyzing unit analyzes that the SDP is included in the INVITE request. 5. The information processing apparatus described in 1. An information processing apparatus that performs SIP communication,
Protocol determination means for determining a transport protocol for SIP communication when an INVITE request is transmitted to the SIP server;
When the protocol determination unit determines that the transport protocol is UDP, SDP media information is selected according to the type of the SIP server, and the transport protocol is TCP or SSL by the protocol determination unit. A selection means for selecting media information of all SDPs,
An information processing apparatus comprising: a transmission unit configured to generate an INVITE request in which the media information of the SDP selected by the selection unit is set and transmit the request to the SIP server. The information processing apparatus according to any one of claims 1 to 6,
An image processing apparatus comprising image processing means for processing an image. A method of controlling an information processing apparatus that performs SIP communication,
A receiving step for receiving an INVITE request from the SIP server;
An analyzing step for analyzing whether or not SDP is included in the INVITE request received in the receiving step;
If the protocol determining means analyzes that the SDP is not included in the INVITE request in the analyzing step, a protocol determining step for determining a transport protocol for SIP communication;
When it is determined that the transport protocol is UDP in the protocol determination step, the selection unit selects SDP media information according to the type of the SIP server, and in the protocol determination step, the transport protocol is TCP Or, if it is determined that it is SSL, a selection step of selecting media information of all SDPs;
And a response step of generating an INVITE response in which the media information of the SDP selected in the selection step is set and responding to the SIP server. A method of controlling an information processing apparatus that performs SIP communication,
A protocol determination step for determining a transport protocol for SIP communication when the protocol determination means transmits an INVITE request to the SIP server;
When it is determined that the transport protocol is UDP in the protocol determination step, the selection unit selects SDP media information according to the type of the SIP server, and the transport protocol is determined to be TCP by the protocol determination step. Or, if it is determined that it is SSL, a selection step of selecting media information of all SDPs;
A control method for an information processing apparatus, comprising: a transmission step of generating an INVITE request in which the media information of the SDP selected in the selection step is set and transmitting the request to the SIP server.   The program for making a computer perform each step in the control method of the information processing apparatus described in Claim 8 or 9.

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