Abstract:
A search device communicates with a first device and a second device through a network. The search device includes a storage unit that stores therein a first telephone number of the first device, a second telephone number of the second device, and a first communication address of the first device in an associated manner; a receiving unit that receives, from the second device, a third telephone number of the first device, a fourth telephone number of the second device, and a second communication address of the second device; an extracting unit that extracts, from the storage unit, a first communication address that corresponds to the third telephone number and the fourth telephone number; and a transmitting unit that transmits extracted first communication address to the second device.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     The present document incorporates by reference the entire contents of Japanese priority document, 2004-270848 filed in Japan on Sep. 17, 2004, and 2005-237439 filed in Japan on Aug. 18, 2005.  
       BACKGROUND OF THE INVENTION  
       [0002]     1. Field of the Invention  
         [0003]     The present invention relates to a technology for communicating electronic data between communication devices that communicate with each other through a network.  
         [0004]     2. Description of the Related Art  
         [0005]     Telephones are the most popular means to communicate information. However, the telephone only enables speech communication. Therefore, the telephone does not satisfy such a demand of a user that a paper document can be exchanged with the other party during a telephone conversation so that the conversation is more understandable.  
         [0006]     For example, it is desired that a pamphlet be immediately provided to a client while a salesperson is discussing business with the client on the telephone. This is because a copy of the pamphlet helps the client more accurately understand the information that the salesperson wants to tell rather than reading out the content of the pamphlet through the telephone.  
         [0007]     Furthermore, there are many cases where a conference material, which is not prepared to be released, happens to be released as answers to questions during a telephone conference. In these cases, it is desired that the conference material be immediately distributed to participants of the telephone conference so that the participants can share the information in the conference material while discussing an issue.  
         [0008]     A technology that can be useful in these cases is disclosed in Japanese Patent Application Laid-Open No. 2000-69133. In this technology, to easily transmit a document, a facsimile on the side of accepting a document acquires a telephone number of a destination facsimile based on transmitting subscriber identification (TSI) to register the telephone number acquired in a telephone-number registration table. This enables a user to easily register a telephone number of a destination facsimile and use the telephone number.  
         [0009]     In the conventional technology, however, although it is useful when the same facsimile is regularly used, for example, in an office, when a user is out of the office, telephone numbers of facsimiles have to be newly entered.  
         [0010]     Technologies called internet protocol version 6 (IpV6) and universal plug and play (UPnP) have been proposed in 1990&#39;s, and they are being developed even now. It is said that when these technologies are widely used, all devices connected to an internet protocol (IP) network recognize each other so that information is exchanged among the devices. Image processors are also included in such devices. Therefore, it is predicted that all the image processors can mutually recognize each other so that image information can be exchanged in an end-to-end manner. For example, an application called “copy machine-to-copy machine” function can be created. This application is such that an image read by a scanner of a copy machine is printed in real time by a printer of a copy machine that is remotely located.  
         [0011]     For realization of the “copy machine-to-copy machine” function, the process to determine a destination largely affects achieving the ease-of-use. In the case of the facsimile, a communication destination is determined by a sender of a document entering a telephone number of a destination facsimile. In a case of the “copy machine-to-copy machine” function, a communication destination is determined by a sender of a document entering an IP address and a media access control (MAC) address of a destination facsimile or entering a proper name from which an address thereof can be solved.  
         [0012]     The method of entering a communication destination in the “copy machine-to-copy machine” function, which is about to be realized on the IP network, requires entry of an IP address and a MAC address, or a unique character/number string from which a relevant address can be solved. Such an operation is complicated for a user and mistakable. Moreover, if an address such as the IP address, by which an image processor can be identified, is disclosed, a document may be sent unilaterally from an unknown person. Consequently, it is an inevitable result that the communication destination is mistaken by the miss operation or that the document is unilaterally distributed by an unidentified person. Therefore, this technique is not always suitable for the “copy machine-to-copy machine” function.  
       SUMMARY OF THE INVENTION  
       [0013]     It is an object of the present invention to at least solve the problems in the conventional technology.  
         [0014]     A search device according to one aspect of the present invention communicates with a first device and a second device through a network. The search device includes a storage unit configured to store therein a first telephone number of the first device, a second telephone number of the second device, and a first communication address of the first device in an associated manner; a receiving unit configured to receive, from the second device, a third telephone number of the first device, a fourth telephone number of the second device, and a second communication address of the second device; an extracting unit configured to extract, from the storage unit, a first communication address that corresponds to the third telephone number and the fourth telephone number; and a transmitting unit configured to transmit extracted first communication address to the second device.  
         [0015]     A communication device according to another aspect of the present invention includes a number acquiring unit configured to acquire a telephone number of the communication device and a telephone number of a second communication device to which the communication device is to transmit electronic data through a network; and an address acquiring unit configured to acquire a communication address of the second communication device based on acquired telephone numbers and a communication address of the communication device.  
         [0016]     A communication device according to still another aspect of the present invention includes an authentication-information acquiring unit configured to acquire authentication information that is arbitrarily determined by users; an authentication-information receiving unit configured to receive authentication information transmitted from a second communication device; a determining unit configured to determine whether received authentication information corresponds with acquired authentication information; and a transmitting unit configured to transmit electronic data to the second communication device when the determining unit determines that the received authentication information corresponds with the acquired authentication information.  
         [0017]     A communication device according to still another aspect of the present invention includes an authentication-information acquiring unit configured to acquire authentication information that is arbitrarily determined by users; an authentication-information receiving unit configured to receive authentication information transmitted from a second communication device; a determining unit configured to determine whether received authentication information corresponds with acquired authentication information; and a disconnecting unit configured to disconnect communication between the communication device and the second communication device after a specific time has elapsed, when the determining unit determines that the received authentication information corresponds with the acquired authentication information.  
         [0018]     A search method according to still another aspect of the present invention is performed by a search device that includes a storage unit and that is configured to communicate with a first device and a second device through a network. The search method includes storing, in the storage unit, a first telephone number of the first device, a second telephone number of the second device, and a first communication address of the first device in an associated manner; receiving, from the second device, a third telephone number of the first device, a fourth telephone number of the second device, and a second communication address of the second device; extracting, from the storage unit, a first communication address that corresponds to the third telephone number and the fourth telephone number; and transmitting extracted first communication address to the second device.  
         [0019]     An acquisition method of acquiring a communication address according to still another aspect of the present invention includes acquiring a telephone number of a first communication device and a telephone number of a second communication device to which the first communication device is to transmit electronic data through a network; and acquiring a communication address of the second communication device based on acquired telephone numbers and a communication address of the first communication device.  
         [0020]     A authentication method according to still another aspect of the present invention is for authenticating users of a first communication device and a second communication device that communicate with each other through a network. The authentication method includes acquiring authentication information that is arbitrarily determined by users; receiving authentication information transmitted from the second communication device; and determining whether received authentication information corresponds with acquired authentication information. The first communication device transmits electronic data to the second communication device when it is determined that the received authentication information corresponds with the acquired authentication information at the determining.  
         [0021]     A disconnection method according to still another aspect of the present invention is for disconnecting communication between a first communication device and a second communication device. The disconnection method includes acquiring authentication information that is arbitrarily determined by users; receiving authentication information transmitted from the second communication device; determining whether received authentication information corresponds with acquired authentication information; and disconnecting the communication after a specific time has elapsed, when it is determined that the received authentication information corresponds with the acquired authentication information at the determining.  
         [0022]     A computer-readable recording medium according to still another aspect of the present invention stores therein a computer program for realizing a search method according to the above aspect.  
         [0023]     A computer-readable recording medium according to still another aspect of the present invention stores therein a computer program for realizing an acquisition method according to the above aspect.  
         [0024]     A computer-readable recording medium according to still another aspect of the present invention stores therein a computer program for realizing an authentication method according to the above aspect.  
         [0025]     A computer-readable recording medium according to still another aspect of the present invention stores therein a computer program for realizing a disconnection method according to the above aspect.  
         [0026]     The above and other objects, features, advantages and technical and industrial significance of this invention will be better understood by reading the following detailed description of presently preferred embodiments of the invention, when considered in connection with the accompanying drawings. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0027]      FIG. 1  is a block diagram of a copy machine according to a first embodiment of the present invention;  
         [0028]      FIG. 2  is a block diagram of a server connected to the copy machine via a network;  
         [0029]      FIG. 3  is a schematic for illustrating a setting screen for read conditions displayed on a liquid-crystal touch panel;  
         [0030]      FIG. 4  is a schematic for illustrating a setting screen for print conditions displayed on the liquid-crystal touch panel;  
         [0031]      FIG. 5  is a schematic for illustrating an entry screen displayed on the liquid-crystal touch panel;  
         [0032]      FIG. 6  is a schematic for illustrating an entry screen for prompting entry from a telephone set;  
         [0033]      FIG. 7A  and  FIG. 7B  are flowcharts of find processes;  
         [0034]      FIG. 8  is a schematic for illustrating a data transmission/reception system according to the first embodiment;  
         [0035]      FIG. 9  is a flowchart of a procedure of compare processes;  
         [0036]      FIG. 10  is a schematic for illustrating an entry screen for entering a password displayed on the liquid-crystal touch panel;  
         [0037]      FIG. 11  is a flowchart of a procedure of a negotiation process;  
         [0038]      FIG. 12A  and  FIG. 12B  are flowcharts of disconnection processes;  
         [0039]      FIG. 13  is a schematic for illustrating a data transmission/reception system according to a second embodiment of the present invention; and  
         [0040]      FIG. 14  is a schematic for illustrating a hardware configuration of the server according to the embodiments. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0041]     Exemplary embodiments according to the present invention are explained in detail below with reference to the accompanying drawings. In the embodiments, a communication device is a copy machine, and a data transmission/reception system includes telephone sets, through which a user and a called party communicate, copy machines that transmit and receive an image, and a server that searches for a communication address of each copy machine. The communication address is used for communication between the copy machines. In the embodiments, users of the data transmission/reception system, in which the “copy machine-to-copy machine” function is implemented on an IP network, are ready to communicate with each other on the telephone (during a telephone connection) with a communication tool, such as a fixed-line phone and a cell phone. When a copy machine transmits or receives image information, a server identifies communication addresses of both the copy machines of the user and the called party, from a telephone number of a telephone used by the user and from a telephone number of a telephone as a called party (as an example of entering telephone numbers of the user&#39;s telephone and the called party&#39;s telephone, there is a method of acquiring incoming and outgoing information by a telephone set interface unit). The following case is explained below. The case is such that copy machines are connected to each other by identifying the communication addresses of the copy machines, to transmit image information input through a scanner or the like.  
         [0042]     In the following, there is shown an example of making the “copy machine-to-copy machine” possible. However, the communication device that constitutes the data transmission/reception system may be any device capable of capturing image information, printing out, and transmitting or receiving an image to or from a network, for example, a scanner, a network printer, or an information processing terminal such as a personal computer (PC) that is connected with a scanner and a printer. The network can be a wired or a wireless network.  
         [0043]      FIG. 1  is a block diagram of a copy machine according to the first embodiment. While the copy machine is explained as an example of the communication device in the first embodiment, a scanner, a printer, a multifunction peripheral, and a PC connected with a printer and a scanner may be used, instead of the copy machine. Referring to  FIG. 1 , a sensor board unit (SBU)  24  optically reads a document, where light irradiated from a light source illuminates the document, and the light reflected thereby is collected to a light receiving element. The light receiving element converts the intensity of the light collected to an analog electrical signal, and a charge-coupled device (CCD) is used as the device in this example. The analog electrical signal output from the CCD is quantized and is output as digital image data from the SBU  24 .  
         [0044]     An image processing processor (IPP)  27  performs image processing on the digital image data. This unit optimizes frequency characteristics and gradation characteristics of the digital image data according to conditions set by a user and device characteristics specific to the machine.  
         [0045]     A communication controller (compression/decompression data interface controller: CDIC)  25  helps smooth transmission or reception of the digital image data performed between the units. The SBU  24  and the IPP  27  perform transmission and reception of the digital image data, always through the CDIC  25 .  
         [0046]     An image memory access controller (IMAC)  14  converts a format of the digital image data to access a memory (MEM)  15 . The MEM  15  stores the digital image data and temporarily accumulates an image read by the SBU  24  and an image sent from an information processing terminal such as another copy machine and a PC through an IP network  50 . The MEM  15  further stores a comparison result as to whether a password entered through a liquid-crystal touch panel  16  and a password transmitted from a copy machine as a called party match each other.  
         [0047]     A network control unit (NCU)  19  performs transmission or reception of the digital data to or from another copy machine and a PC, which are connected to the IP network  50 . Upon transmission, the NCU  19  processes the data according to a communication protocol of the IP network  50 , and outputs the data processed to the IP network  50 . Upon reception, the NCU  19  reproduces original reception data from the data processed according to the communication protocol. Further, the NCU  19  can receive an IP address of a copy machine as a called party.  
         [0048]     The NCU  19  transmits a user&#39;s telephone number, a called party&#39;s telephone number obtained from a telephone interface unit (TIFU)  17  or from the liquid-crystal touch panel  16 , and an IP address stored in read only memory (ROM ( 1 ))  12 , to a server  200 . The user&#39;s telephone number is a telephone number of a telephone set  71  (as a representative of  71   a,    71   b,  and  71   c ), through which a user using a copy machine  100  (as a representative of  100   a ,  100   b,  and  100   c ) is in conversation with a called party. That is, the user&#39;s telephone number is user&#39;s identification information for identifying a user. The called party&#39;s telephone number is a telephone number of the telephone set  71  as the called party, that is, the called party&#39;s telephone number is other party&#39;s identification information for identifying the other party. The IP address is used for identifying the copy machine  100  in the IP network. While the case where the IP address is used as a communication address is explained in the first embodiment, an MAC address, an E-mail address, and a specific character/number string, from which a relevant address can be solved, may be used instead of the IP address.  
         [0049]     The NCU  19  receives a password of the other party transmitted from the copy machine  100  used by the other party.  
         [0050]     The TIFU  17  performs transmission or reception of the digital data to or from a telephone set  71  (see  FIG. 13 ) used by the user of the copy machine  100  for making a call. The TIFU  17  mainly acquires information on a call such as a user&#39;s telephone number (called party&#39;s telephone number), and outgoing and incoming calls.  
         [0051]     A wireless short-distance communication standard (e.g., radio frequency identification (RFID) and Bluetooth) is preferably employed for communication between the copy machine  100  and the telephone set  71 . Employment of this standard has some advantages such that there is no need to connect between the two with a communication cable or the like, which does not restrict a telephone calling environment. Moreover, in the case of short-distance communication, a cross talk with another telephone set is possibly avoided. Recently, a plurality of companies and organizations try mounting a function of electronic money or electronic ticket on cell phones. As a method of acquiring money information or ticket information from the cell phone, the standard of wireless short-distance communication is employed. Therefore, there is a large possibility, in the near future, that telephone sets with a built-in interface for the wireless short-distance communication are distributed in the market, and hence, employment of this method is highly convenient.  
         [0052]     The telephone set  71  holds a telephone number of the relevant telephone set (or a first telephone set)  71 , and acquires a telephone number of a telephone set as a called party (or a second telephone set) that is in telephone connection, from the second telephone set using an other party&#39;s number notifying function. When having received a signal from the TIFU  17  of the copy machine  100 , the first telephone set  71  transmits the telephone number of the first telephone set  71  and the telephone number of the second telephone set.  
         [0053]     A video control unit (VCU)  28  reproduces an image on a sheet of paper. The VCU  28  determines a position, a size, and a color of dots to be printed on the sheet, from digital image data received from the IPP  27 , and prints the dots by a plotter, to reproduce the image on the sheet.  
         [0054]     An auto payment unit (APU)  18  collects a fee for use of the copy machine  100  from a user. The APU  18  has a slot for a bill and a coin, and a tray for change, so that the user can pay for it in advance. Collecting is carried out each time the fee occurs, and if there is the balance after all the operations are finished, part of payment is returned as change. Further, the APU  18  charges based on a set charging rate. The APU  18  can employ the way to collect a fee at an arbitrary rate from both sides or one side of the copy machine  100  used by the user and the copy machine  100  used by the other party.  
         [0055]     The liquid-crystal touch panel  16  displays information (display of guidance of operations or so) required for the user to use the copy machine  100 , and its display screen is touched by the user, thereby allowing the user to perform a setting operation.  
         [0056]     The liquid-crystal touch panel  16  accepts an input of a charging rate for transmission of image data on the user and the called party. The liquid-crystal touch panel  16  also accepts an input whether to transmit image information to the other party.  
         [0057]     A process controller  20  controls the operations of the SBU  24 , the CDIC  25 , the IPP  27 , and the VCU  28 . Therefore, the process controller  20  sets respectively required operation conditions, and monitors how each component is started, ended, and how respective processes are progressing.  
         [0058]     A system controller  10  controls the operations of the IMAC  14 , the NCU  19 , the MEM  15 , the liquid-crystal touch panel  16 , the TIFU  17 , and the APU  18 . Therefore, the system controller  10  sets respectively required operation conditions, and monitors how each component is started, ended, and how respective processes are progressing.  
         [0059]     Further, the system controller  10  compares the user&#39;s password entered through the liquid-crystal touch panel  16  with the other party&#39;s password transmitted from the copy machine of the other party, to determine whether there is a match. When a predetermined time has elapsed from the time when “match” has been stored in the MEM  15  as the result of comparison, the system controller  10  stores “non-match” as the result of comparison in the MEM  15 . When a predetermined time has elapsed from the time when “non-match” has been stored in the MEM  15  as the result of comparison and it is determined that the passwords do not match as the comparison process of the passwords, the system controller  10  instructs to disconnect the communication line.  
         [0060]     The RAM( 1 )  11  and read only memory (ROM)( 1 )  12  connected to the IMAC  14  through a local bus store information required for processes performed by the system controller  10 , the IMAC  14 , the liquid-crystal touch panel  16 , the MEM  15 , the NCU  19 , the TIFU  17 , and the APU  18 . The information includes, for example, text information and bitmap information for displaying a character and a pattern on the liquid-crystal touch panel  16 , a total amount and a remaining amount of the digital image data that can be accumulated in the MEM  15 , protocol information for making access from the NCU  19  to an information processing terminal, and information entered by a user through the liquid-crystal touch panel  16 . When a processor is installed in those such as the IMAC  14 , the liquid-crystal touch panel  16 , the MEM  15 , the NCU  19 , the TIFU  17 , the APU  18 , and the system controller  10 , a program that describes each operation is also stored in the ROM( 1 )  12 . The IP address of the copy machine according to the first embodiment is further stored therein.  
         [0061]     RAM( 2 )  21  and ROM( 2 )  22  connected to a serial bus store information required for processes performed by the SBU  24 , the CDIC  25 , the IPP  27 , the VCU  28 , and the process controller  20 . The information includes, for example, the size of an image to be read by the SBU  24 , optical characteristics of the CCD, and parameters for image processing executed by the IPP  27 . When a processor is installed in those in the SBU  24 , the CDIC  25 , the IPP  27 , the VCU  28 , and the process controller  20 , a program that describes each operation is also stored in the ROM( 2 )  22 .  
         [0062]     A printing unit (not shown) outputs image information transmitted from a copy machine of a called party.  
         [0063]     A transmission/reception-address setting program, an authentication-information comparison program, and a communication-line disconnection program are executed by the copy machine  100  according to the first embodiment, and they are preinstalled in the ROM( 1 )  12  or the ROM( 2 )  22 , and are provided.  
         [0064]     The transmission/reception-address setting program, the authentication-information comparison program, and the communication-line disconnection program may also be provided by being recorded in a computer-readable recording medium such as a compact disk (CD)-ROM, a flexible disk (FD), a CD-recordable (R), and a digital versatile disk (DVD) with a file in an installable form or an executable form.  
         [0065]     An address inquiry program, the authentication-information comparison program, the communication-line disconnection program executed by the copy machine  100  may be provided by being stored in a computer connected to a network such as the Internet and being downloaded through the network. Furthermore, the transmission/reception-address setting program, the authentication-information comparison program, and the communication-line disconnection program may be provided or distributed through the network.  
         [0066]     The address inquiry program, the authentication-information comparison program, the communication-line disconnection program allow the computer to realize each unit (such as an identification-information acquiring unit, a user-information transmitting unit, a user-information receiving unit, an authentication-information acquiring unit, an authentication-information receiving unit, an authentication-information comparing unit, an image-information transmitting unit, a comparison-result invalidating unit, and a communication-line disconnecting unit).  
         [0067]      FIG. 2  is a block diagram of a server connected to the copy machine via the IP network  50 . Instead of the IP network  50 , any one of networks such as a local area network (LAN) and a radio communication network may be used. The server  200  includes a user-information receiving unit  201 , a called party search unit  202 , an address search unit  203 , an address transmitting unit  204 , and a user information database  210 . The server  200  constitutes the search device for addresses according to the present invention.  
         [0068]     The user-information receiving unit  201  receives a user&#39;s telephone number and a called party&#39;s telephone number, and an IP address of the copy machine  100  used by a user, which are transmitted from the copy machine  100 . The called party search unit  202  searches for and acquires user information transmitted from a copy machine as the other party, from the user information database  210  based on the called party&#39;s telephone number and the user&#39;s telephone number received.  
         [0069]     The address search unit  203  searches for an IP address of the copy machine  100  used by the called party, from the user information for the called party acquired by the called party search unit  202 . The address transmitting unit  204  transmits the IP address of the copy machine  100  of the other party. The user information database  210  stores the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address used by the user, which are received by the user-information receiving unit  201 , in such a manner that these are associated to one another as user information. An example of the contents of the user information database  210  is shown in  FIG. 8 .  
         [0070]      FIG. 14  is a schematic for illustrating a hardware configuration of the server  200  according to the embodiments. The server  200  includes a controller such as a central processing unit (CPU)  31 , a storage device such as ROM  32  and RAM  33 , an external storage device such as a hard disk drive (HDD)  34  and a CD drive  35 , a display device such as a display unit  36 , and an input device such as a keyboard  38  and a mouse  39 . These components communicate with one another through a bus controller  40 , and are connected to the IP network  50  through a network interface  37 , to configure ordinary hardware using a computer.  
         [0071]     An address search program executed by the server  200  can be recorded in a computer-readable recording medium such as a CD-ROM, an FD, a CD-R, and a DVD with a file in an installable form or an executable form. The address search program may also be preinstalled in the built-in ROM or the like, and provided.  
         [0072]     The address search program executed by the server  200  may be provided by being stored in a computer connected to the IP network  50  and being downloaded through the IP network  50 . Furthermore, the address search program executed by the server  200  may be provided or distributed through the network such as the Internet.  
         [0073]     The address search program executed by the server  200  allows the computer to realize each unit (such as the user-information receiving unit, the called party search unit, the address search unit, and the address transmitting unit).  
         [0074]     Specific operations of respective basic operations performed by the copy machine  100  are explained below. The basic operations include “scan to memory operation”, “memory to print operation”, “memory to network operation”, “network to memory operation”, “find operation”, “compare operation”, “negotiation operation”, and “disconnect operation”.  
         [0075]     The “scan to memory operation” is an operation such that the copy machine  100  reads a document by the SBU  24  and stores digital image data obtained in the MEM  15 . The user puts the document on a document table provided in the SBU  24 , and sets read conditions which are variable by an input operation through the liquid-crystal touch panel  16 .  FIG. 3  is a diagram for explaining a setting screen  16   a  for read conditions displayed on the liquid-crystal touch panel  16 . In  FIG. 3 , there are choices of eight types for specifying a read area, and choices of three types for setting read resolution displayed thereon. Respective keys for choice, and confirm (OK) button and cancel button for setting are also displayed thereon.  
         [0076]     By specifying the read area and setting the read resolution through the operation of the respective keys, and by pressing the confirm button, the read conditions set by the user are transmitted to the process controller  20  and the system controller  10 , respectively.  
         [0077]     The process controller  20  stores the read conditions received in the RAM( 2 )  21 , and instructs the SBU  24 , the CDIC  25 , and the IPP  27  to perform the operations according to the read conditions.  
         [0078]     The system controller  10  stores the read conditions received in the RAM( 1 )  11 , and instructs the IMAC  14  and the MEM  15  to perform the operations according to the read conditions. After completion of the instructions to the units, the SBU  24  reads the document set on the document table, and transmits digital image data for the document to the CDIC  25 . The CDIC  25  transmits the digital image data received to the IPP  27 . The IPP  27  performs image processing thereon to compensate for optical characteristics of the SBU  24 , and transmits the digital image data image-processed to the CDIC  25 . The CDIC  25  transmits the digital image data received to the IMAC  14  through a parallel bus. The IMAC  14  converts the digital image data to a form so as to be accumulated in the MEM  15 .  
         [0079]     During the operations, the respective statuses of the SBU  24 , the IPP  27 , and the CDIC  25  are sequentially notified to the process controller  20 , and the respective statuses of the IMAC  14  and the MEM  15  are sequentially notified to the system controller  10 . When storage of the digital image data is finished, the system controller  10  displays a message to this effect on the liquid-crystal touch panel  16 , and finishes the “scan to memory operation”.  
         [0080]     The “memory to print operation” is an operation such that the copy machine  100  prints out the digital image data stored in the MEM  15  onto the sheet, as a reproduced image. The user sets print conditions, which are variable, by an input operation through the liquid-crystal touch panel  16 .  FIG. 4  is a schematic for illustrating a setting screen  16   b  for print conditions displayed on the liquid-crystal touch panel  16 . In  FIG. 4 , there are choices of eight types for specifying a print paper, and choices of two types for setting print quality displayed thereon. Respective keys for choice, and confirm (OK) button and cancel button for setting are also displayed thereon.  
         [0081]     By specifying the print paper and setting the print quality through the operation of the respective keys, and by pressing the confirm button, the copy machine  100  transmits the print conditions set by the user to the process controller  20  and the system controller  10 , respectively.  
         [0082]     The process controller  20  stores the print conditions received in the RAM( 2 )  21 , and instructs the CDIC  25 , the IPP  27 , and the VCU  28  to perform the operations according to the print conditions. The system controller  10  stores the print conditions received in the RAM( 1 )  11 , and instructs the IMAC  14  and the MEM  15  to perform the operations according to the print conditions.  
         [0083]     After completion of the instructions to the units, the IMAC  14  reads the digital image data used for printing, from the MEM  15 , and recovers it into the image form before the image is stored. The IMAC  14  then transmits the image data to the CDIC  25  through the parallel bus. The CDIC  25  transmits the image data received to the IPP  27 .  
         [0084]     The IPP  27  performs image processing on the image data to compensate for print conditions set by the user and print characteristics of the VCU  28 , and transmits the digital image data image-processed to the VCU  28 . The VCU  28  plots the sheet using the digital image data transmitted from the IPP  27 , to reproduce the image. During the operations, the respective statuses of the CDIC  25 , the IPP  27 , and the VCU  28  are sequentially notified to the process controller  20 , and the respective statuses of the IMAC  14  and the MEM  15  are sequentially notified to the system controller  10 . When reproduction of the image by the VCU  28  is finished, the process controller  20  displays a message to this effect on the liquid-crystal touch panel  16 , and finishes the “memory to print operation”.  
         [0085]     The “memory to network operation” is an operation such that the copy machine  100  transmits the digital image data stored in the MEM  15  to an external copy machine connected to the IP network  50 .  
         [0086]     The IMAC  14  reads the digital image data from the MEM  15  and recovers it to the image form before it is stored, and then transmits the digital image data to the CDIC  25  through the parallel bus.  
         [0087]     The CDIC  25  transmits the digital image data transmitted from the IMAC  14  to the IPP  27 . The IPP  27  subjects the digital image data to image processing such that it is converted into an image form so as to be transferable to the IP network  50 . The digital image data image-processed in the IPP  27  is again transmitted to the CDIC  25 .  
         [0088]     The CDIC  25  transmits the digital image data transmitted from the IPP  27  to the NCU  19  through the parallel bus. The NCU  19  divides the digital image data into pieces of packet data and outputs them to the IP network  50 . During the operations, the respective statuses of the IMAC  14 , the MEM  15 , and the NCU  19  are sequentially notified to the system controller  10 .  
         [0089]     When the NCU  19  finishes the output of the digital image, the system controller  10  displays a message to this effect on the liquid-crystal touch panel  16 , to finish the “memory to network operation”. The digital image data output onto the IP network  50  has been processed so as to follow a communication protocol of the IP network  50 , and hence, the digital image data reaches up to a copy machine as a destination through various types of information processing terminals.  
         [0090]     The “network to memory operation” is an operation such that the copy machine  100  receives digital image data sent from an external copy machine or from an information processing terminal connected to the IP network  50 , and accumulates it in the MEM  15 .  
         [0091]     The NCU  19  recovers the packet data transmitted through the IP network  50  to the digital image data, and transmits the digital image data recovered to the CDIC  25  through the parallel bus.  
         [0092]     The CDIC  25  transmits the digital image data transmitted from the NCU  19  to the IPP  27 . The IPP  27  performs image processing on the digital image data transmitted from the CDIC  25  so as to be converted to an image form adequate for use in the machine, and again transmits the digital image data after the processing to the CDIC  25 .  
         [0093]     The CDIC  25  transmits the digital image data transmitted from the IPP  27  to the IMAC  14  through the parallel bus. The IMAC  14  converts the digital image data to a storage form specified by the MEM  15 , to store it in the MEM  15 . During the operations, the respective statuses of the IMAC  14 , the MEM  15 , and the NCU  19  are sequentially notified to the system controller  10 . When the storage of the digital image in the MEM  15  is finished, the system controller  10  displays a message to this effect on the liquid-crystal touch panel  16 , to finish the “network to memory operation”.  
         [0094]     The “find operation” indicates an operation such that the copy machine  100  acquires destination information for a copy machine of the other party. That is, in the “find operation”, the copy machine  100  acquires a user&#39;s telephone number and a called party&#39;s telephone number, and transmits the user&#39;s telephone number and the called party&#39;s telephone number acquired and a communication address of the copy machine  100  held by the copy machine  100 , to the server  200 . The server  200  stores the user&#39;s telephone number, the called party&#39;s telephone number, and the communication address of the copy machine of the user received, in such a manner that these are related to one another. The server  200  searches for a communication address of a copy machine used by the other party based on the user&#39;s telephone number and the called party&#39;s telephone number, and transmits the communication address of the copy machine of the other party to the copy machine  100 .  
         [0095]     In this case, a specific method is employed in such a manner that when both users of the data transmission/reception system are communicating on the telephone, respective pieces of destination information as IP addresses of copy machines used by the users are determined from the user&#39;s telephone number and the called party&#39;s telephone number of the telephone sets being used for the telephone conversation, to acquire the respective pieces of destination information.  
         [0096]     There are two types of methods as to how the copy machine  100  acquires a user&#39;s telephone number and a called party&#39;s telephone number. One of them as a first method is that the user manually inputs the user&#39;s telephone number and the called party&#39;s telephone number into the copy machine  100 . The other one as a second method is that the copy machine  100  and the telephone set  71  perform communication using the TIFU  17  so that the copy machine  100  acquires the user&#39;s telephone number and the called party&#39;s telephone number.  
         [0097]     The process procedure for the first method of manually inputting these numbers is explained below. The user enters the user&#39;s telephone number and the called party&#39;s telephone number by an input operation to the liquid-crystal touch panel  16 .  
         [0098]      FIG. 5  is a schematic for illustrating an entry screen  16   c  displayed on the liquid-crystal touch panel  16 . In  FIG. 5 , a prompt to enter the user&#39;s telephone number and the called party&#39;s telephone number is displayed thereon, and boxes for entering the respective telephone numbers of the telephone sets used by the user and the called party, the numeric keypad for entry, and “confirm (OK) button” and “cancel button” for the entry are also displayed thereon.  
         [0099]     The user uses the numeric keypad provided on the entry screen to enter the user&#39;s telephone number and the called party&#39;s telephone number, and presses the “confirm button” when all the entries are complete. When the “confirm button” is pressed, the liquid-crystal touch panel  16  notifies the system controller  10  of the entry result confirmed. When receiving the notification, the system controller  10  stores the user&#39;s telephone number and the called party&#39;s telephone number in the RAM( 1 )  11 .  
         [0100]     The process procedure for the second method of entering these numbers using the TIFU  17  is explained below. The liquid-crystal touch panel  16  displays a button indicating “acquire from telephone” in the entry screen  16   c  ( FIG. 5 ). When this button is pressed, the liquid-crystal touch panel  16  is switched to a screen that instructs communication between the copy machine  100  and the telephone set  71 .  
         [0101]      FIG. 6  is a schematic for illustrating an entry screen  16   d  for prompting entry from the telephone set  71 . In  FIG. 6 , a message for notifying that the copy machine  100  and the telephone set  71  used for making a call will perform communication, and “start button” and “cancel button” for prompting execution/cancellation are displayed thereon.  
         [0102]     When the second method is to be executed, the user puts the telephone set  71  used for a telephone conversation, close to the copy machine  100  according to the guidance displayed on the entry screen of  FIG. 6 , to press the “start button” on the entry screen of the liquid-crystal touch panel  16 . When the “start button” is pressed, the liquid-crystal touch panel  16  notifies the system controller  10  of the entry result such that execution is instructed.  
         [0103]     After reception of this notification, the system controller  10  performs communication with the telephone set  71  using the TIFU  17 , to acquire the user&#39;s telephone number and the called party&#39;s telephone number. The system controller  10  then stores these telephone numbers acquired in the RAM( 1 )  11 .  
         [0104]     The system controller  10  uses the NCU  19  to transmit the IP address specific to the copy machine  100 , the user&#39;s telephone number and the called party&#39;s telephone number acquired in the above manner, and the communication address of the copy machine  100  to the server as an external information source. The server  200  checks information to be managed, and searches for destination information for a copy machine that is used by the other party, required for operation of “copy machine-to-copy machine” on the IP network  50 , to acquire the destination information. The server  200  transmits the destination information acquired to the copy machine  100 .  
         [0105]      FIG. 7A  and  FIG. 7B  are flowcharts for procedures of the Find process. A user A and a user B, which are about to transmit and receive image data, are talking on the telephone using the telephone set  71   a  and the telephone set  71   b.  The copy machine  100   a  used by the user A acquires the user&#39;s telephone number and the called party&#39;s telephone number (step S 701 ). More specifically, the copy machine  100   a  acquires “029-361-tttt” being the user&#39;s telephone number of the telephone set  71   a  used by the user A and “053-442-ssss” being the called party&#39;s telephone number of the telephone set  71   b  of the user B that is the called party of the user A, from the telephone set  71   a  of the user A. The telephone set  71   a  holds the telephone number of the telephone set  71   b  of the user B that is the called party of the user A by the other party&#39;s number notifying function that is included in the telephone set  71   a  itself.  
         [0106]     In order to inquire about a communication address of the copy machine  100   b  as the other party, the copy machine  100   a  transmits two telephone numbers (the user&#39;s telephone number and the called party&#39;s telephone number) acquired and the IP address of the copy machine  100   a  held by the copy machine  100   a  itself, to the server  200  (step S 702 ). More specifically, the copy machine  100   a  transits the user&#39;s telephone number “029-361-tttt”, the called party&#39;s telephone number “053-442-ssss”, and the IP address of the copy machine  100   a.  The server  200  receives the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address of the copy machine  100   a  transmitted from the copy machine  100   a  (step S 703 ). The server  200  stores these telephone numbers and the IP address of the copy machine  100   a  received, in the user information database  210  (step S 704 ).  
         [0107]     The copy machine  100   b  used by the user B acquires a user&#39;s telephone number and a called party&#39;s telephone number (step S 705 ). More specifically, the copy machine  100   b  acquires “053-442-ssss” being the user&#39;s telephone number of the telephone set  71   b  used by the user B and “029-361-tttt” being the called party&#39;s telephone number of the telephone set  71   a  of the user A that is the called party of the user B, from the telephone set  71   b  being used by the user B. The telephone set  71   b  holds the telephone number of the telephone set  71   a  of the user A that is the called party of the user B by the other party&#39;s number notifying function that is included in the telephone set  71   b  itself.  
         [0108]     In order to inquire about a communication address of the copy machine  100   a  as the other party, the copy machine  100   b  transmits two telephone numbers (the user&#39;s telephone number and the called party&#39;s telephone number) and the IP address of the copy machine  100   b  held by the copy machine  100   b  itself acquired, to the server  200  (step S 706 ). More specifically, the copy machine  100   b  transmits the user&#39;s telephone number “053-442-ssss”, the called party&#39;s telephone number “029-361-tttt”, and the IP address of the copy machine  100   b.  The server  200  receives the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address of the copy machine  100   b  transmitted from the copy machine  100   b  (step S 707 ). The server  200  stores these telephone numbers and the IP address of the copy machine  100   b  received, in the user information database  210  in such a manner that these are related to one another (step S 708 ).  
         [0109]     In order to acquire an IP address of the copy machine  100   a,  the server  200  finds out an IP address of the copy machine  100   b  used by the user B that is the other party of the user A, from the user information database  210  (step S 709 ). In other words, the server  200  searches the user information database  210  using those, as a search key, obtained by replacing the user&#39;s telephone number and the called party&#39;s telephone number transmitted from the copy machine  100  with each other, and acquires a set of the user&#39;s telephone number and the called party&#39;s telephone number as the search target, the set having the same telephone numbers as the search key. The server  200  acquires the IP address of the copy machine  100   b,  which is related to the user&#39;s telephone number and the called party&#39;s telephone number, as the destination information. This case is more specifically explained with reference to the content of the user information database of  FIG. 8 . If the user&#39;s telephone number of the user A is “029-361-tttt” and the called party&#39;s telephone number is “053-442-ssss”, the server  200  searches for the user information such that the user&#39;s telephone number of the user A is “053-442-ssss” and the called party&#39;s telephone number is “029-361-tttt”, from the user information database  210  of the server  200 . The IP address of the copy machine  100   b  used by the user B is searched for from this user information. As the result of this process, it is found out that the IP address of the copy machine  100   b  used by the user B that is the other party of the user A is “ff00:0101:0218:1224:0126:9723:0640:xxxx”.  
         [0110]     The server  200  transmits the IP address of the copy machine  100   b  as the other party, to the copy machine  100   a  (step S 710 ). The copy machine  100   a  receives the IP address of the copy machine  100   b  as the other party, from the server  200  (step S 711 ).  
         [0111]     In order to acquire an IP address of the copy machine  100   b,  the server  200  finds out the IP address of the copy machine  100   a  used by the user A that is the other party of the user B, from the user information database  210  (step S 712 ). This case is more specifically explained with reference to the content of the user information database of  FIG. 8 . If the user&#39;s telephone number of the user B is “053-442-ssss” and the called party&#39;s telephone number is “029-361-tttt”, the server  200  searches for and acquires the user information such that the user&#39;s telephone number of the user A is “029-361-tttt” and the called party&#39;s telephone number is “053-442-ssss”, from the user information database  210  of the server  200 , conversely to the case of the user A. The IP address is identified from this user information acquired. As the result of this process, it is found out that the IP address of the copy machine  100   a  used by the user A that is the other party of the user B is “0123:4567:02D8:1324:1068:9453:yyyy”.  
         [0112]     The server  200  transmits the IP address of the copy machine  100   a  that is the other party of the copy machine  100   b,  to the copy machine  100   b  (step S 713 ). The copy machine  100   b  receives the IP address of the copy machine  100   a  as the other party (step S 714 ).  
         [0113]     Since the copy machine  100   a  acquires the IP address of the copy machine  100   b,  the copy machine  100   a  transmits a connection request signal to the copy machine  100   b,  to request a connection (step S 715 ). The copy machine  100   b  receives the connection request signal from the copy machine  100   a  (step S 716 ). The copy machine  100   b  transmits a connection permission signal, to permit the connection (step S 717 ). The copy machine  100   a  receives the connection permission signal transmitted from the copy machine  100   b  (step S 718 ). Thereafter, the copy machine  100   a  executes the “scan to memory operation”, and the copy machine  100   b  executes the “memory to print operation”. Text data read from the copy machine  100   a  used by the user A is thereby transmitted to the copy machine  100   b  used by the user B. As a result, the user B can acquire required text data from a nearby copy machine with an easy operation.  
         [0114]     The process of storing the user information in the user information database  210  of the server  200  (step S 701  to step S 704 , and step S 705  to step S 708 ) is an independent process performed by the copy machine  100   a  or the copy machine  100   b , and hence, either one of the processes may be performed prior to the other process, or the processes may be performed in parallel.  
         [0115]     In this manner, a first copy machine used by a user transmits the user&#39;s telephone number, the called party&#39;s telephone number, and the communication address of the first copy machine to a server, and the server acquires a communication address of a second copy machine as the other party, to connect between the first and second copy machines. In this case, there is no need for the user to specify an IP address and a MAC address which require such an operation that is troublesome and easy to make a mistake, or to specify a specific character/number string from which a relevant address can be solved. This case allows easy transmission and reception of image information between the first and second copy machines.  
         [0116]     A copy machine acquires the user&#39;s telephone number and the called party&#39;s telephone number from a telephone set through short-distance communication, and transmits these telephone numbers together with the communication address of the copy machine, to a server. Consequently, image information can be transmitted and received between the copy machines with easier operation where there is no need for the user to manually enter the user&#39;s telephone number and the called party&#39;s telephone number.  
         [0117]     Because there is no need to enter an IP address and a MAC address which are very complicated and difficult to remember and there is no need to enter a specific name from which a relevant address can be solved, a character string including an alphanumeric character and a symbol is unnecessary to be entered, thereby preventing miss-operation due to typing errors by a user. By entering such a telephone number that every one is accustomed to handle, in the copy machine, connection with a desired copy machine can be established without user&#39;s being conscious of an IP address assigned to the copy machine at destination. Therefore, a system with high operability for users can be provided.  
         [0118]     Moreover, since a user has made a contact, through a telephone, with a person to whom a document is transmitted, the user can transmit the text data to the person that is identified, with a sense of security.  
         [0119]     Since users can acquire respective IP addresses of copy machines, which are not mutually known by the users, through the server  200 , copy machines which have never exchanged text data can transmit and receive the text data. Therefore, even when the user A is in the office and the user B is somewhere outside the office, the user A can send text data from the copy machine in the office to any copy machine near the user B that is outside the office.  
         [0120]     Since the IP address, the MAC address, and the specific name are not made open, malicious actions (junk e-mails) such that advertisement and solicitation e-mails are sent to the general public can be prevented.  
         [0121]      FIG. 8  is a schematic for illustrating the data transmission/reception system according to the first embodiment. The data transmission/reception system is constructed by respectively connecting the copy machine  100   a,  the copy machine  100   b,  and the copy machine  100   c,  and the server  200  being an external information source, to the IP network  50 . The server  200  collects the user&#39;s telephone numbers, the called party&#39;s telephone numbers, and the IP addresses from the copy machine  100   a , the copy machine  100   b,  and the copy machine  100   c,  respectively, to manage these data as a database.  
         [0122]     For example, in order to acquire destination information for a copy machine as the other party, the copy machine  100   a  transmits the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address to the server  200 . When the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address are transmitted from the copy machine  100   a , the server  200  acquires an IP address related to a user&#39;s telephone number and a called party&#39;s telephone number from the user information database  210 , the IP address being obtained by replacing the user&#39;s telephone number and the called party&#39;s telephone number acquired from the copy machine  100   a  with each other. The server  200  sends the IP address acquired from the user information database  210  as an IP address of the copy machine  100   b,  to the copy machine  100   a.    
         [0123]     When the destination information cannot be found out instantly even after the searching, the server  200  notifies the copy machine  100   a  of such an effect that it is during searching, and continues the searching. If the destination information cannot be found out from the database in a predetermined time, the server  200  notifies the copy machine  100   a  of failure of the searching, and terminates the searching.  
         [0124]     If three or more telephone sets are used to have a telephone conversation among multi-parties, the server  200  searches for a plurality of copy machines each corresponding to the copy machine  100   b  in the above case. In this case, the server  200  sends the IP addresses of all the copy machines obtained through the search result as required destination information, to the copy machine  100   a.  The server  200  also sends the IP address of the copy machine as destination information, to respective copy machines from which the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address are transmitted.  
         [0125]     The copy machine  100   a  transmits the user&#39;s telephone number, the called party&#39;s telephone number, and the IP address to the server  200 , and waits for destination information for the other party sent from the server  200 . When receiving the destination information from the server  200 , the copy machine  100   a  stores the destination information received in the RAM( 1 )  11 , to finish “find operation”. In this case, if “during searching” is notified, the copy machine  100   a  displays a message to this effect on the liquid-crystal touch panel  16 , and continues waiting for the destination information. If “failure of searching” is notified, the copy machine  100   a  displays a message to this effect on the liquid-crystal touch panel  16 , to finish “find operation”.  
         [0126]     The “compare operation” is an operation such that the copy machine  100  acquires a password from a user to check image information that is to be transmitted and received for performing the operation of “copy machine-to-copy machine”, transmits the password acquired to a copy machine connected thereto and receives a password therefrom, and compares the passwords with each other to determine whether the passwords match each other.  
         [0127]     The compare process based on the two copy machines configured in the above manner is explained below.  FIG. 9  is a flowchart of the compare process.  
         [0128]     The user A and the user B, that are about to transmit and receive image data, are talking using the telephone set  71   a  and the telephone set  71   b,  and decide on a mutual password with each other. The copy machine  100   a  accepts an input of the user A&#39;s password entered by the user A (step S 901 ). The copy machine  100   a  transmits the user A&#39;s password to the copy machine  100   b  (step S 902 ). The copy machine  100   b  receives the user A&#39;s password transmitted from the copy machine  100   a  (step S 903 ).  
         [0129]     The copy machine  100   b  accepts an input of the user B&#39;s password entered by the user B (step S 904 ). The copy machine  100   b  transmits the user B&#39;s password to the copy machine  100   a  (step S 905 ). The copy machine  100   a  receives the user B&#39;s password transmitted from the copy machine  100   b  (step S 906 ).  
         [0130]     The copy machine  100   a  compares the user A&#39;s password with the user B&#39;s password transmitted to determine whether the user A and the user B are talking on the telephone (step S 907 ). The copy machine  100   a  stores the comparison result of the passwords in a comparison result storage unit (step S 908 ). More specifically, if there is a match between the passwords, then “match” is stored therein as the comparison result, but if there is no match, then “non-match” is stored therein as the comparison result. The copy machine  100   a  displays the comparison result of the passwords on the liquid-crystal touch panel  16  (step S 909 ).  
         [0131]     The copy machine  100   b  compares the user B&#39;s password with the user A&#39;s password transmitted (step S 910 ). The copy machine  100   b  stores the comparison result of the passwords in a comparison result storage unit (step S 911 ). The copy machine  100   b  displays the comparison result of the passwords on the liquid-crystal touch panel  16  (step S 912 ).  
         [0132]     The transmission process of the password (steps S 901  to S 903 , and steps S 904  to S 906 ) is the process independently performed by the copy machine  100   a  or the copy machine  100   b,  and hence, either one of the processes may be performed prior to the other process, or the processes may be performed in parallel.  
         [0133]     In this manner, since the copy machine according to the first embodiment includes the “compare operation”, even if the connection is established by the “find operation”, transmission or reception of the text is not started before the mutual password is entered. Therefore, the text data can reliably be transmitted and received between those that talk on the telephone. Moreover, the mutual password is decided on the spot by the users that are talking on the telephone, that is, the mutual password is not previously stored, which allows transmission and reception of text with high reliability without worrying about password theft by hacking or the like.  
         [0134]     Even after the connection with a desired copy machine is established, the users can identify each other, to enable transmission and reception of text data that requires high security. For example, even when the user views various Web sites by clicking on a hyperlink over the Internet displayed on the screen with a pointing device such as a mouse, the user can confirm transaction of the text data with the other party on the telephone, thereby preventing the user from being involved in crime such as a phishing scam.  
         [0135]      FIG. 10  is a schematic for illustrating an entry screen  16   f  for entry of a password, displayed on the liquid-crystal touch panel  16 . The copy machine  100  displays a message for prompting entry of a mutual password decided by both the user and the other party, that transmit and receive image information, and displays an entry box for the password, a numeric keypad used for entry of data, and “confirm (OK) button” and “cancel button” for entry of the data.  
         [0136]     The user enters the mutual password decided using the numeric keypad. The mutual password can be decided by the users that mutually accept it through the talking on the telephone, and four digits of numbers are used as the password in  FIG. 10 . The user enters the password using the numeric keypad and presses the “confirm button”, thereby the liquid-crystal touch panel  16  makes the entry complete. When the “confirm button” is pressed, the liquid-crystal touch panel  16  notifies the system controller  10  of entry completion.  
         [0137]     After reception of the notification, the system controller  10  stores the password entered in the RAM( 1 )  11 . The system controller  10  exchanges the password entered into the copy machine and the password entered into a copy machine used by the other party, and compares the passwords with each other. If there is a match between the passwords, then the system controller  10  displays a message to that effect on the liquid-crystal touch panel  16 , to finish the “compare operation”. If there is no match therebetween, the system controller  10  displays a message for prompting reentry of the passwords on the liquid-crystal touch panel  16 , and performs again the “compare operation”. If there is no match even after the operation is performed predetermined times, the system controller  10  terminates transmission or reception of image information.  
         [0138]     The “negotiation operation” is such that the copy machine  100  is made to perform an operation in which the result of negotiation between the user and the other party is reflected before the copy machine  100  performs transmission or reception of image information. For example, if a plurality of copy machines  100  are connected to each other, setting becomes possible for each copy machine  100  according to the result of negotiation as to whether transmission or reception of the image information is executed.  
         [0139]     If the use of the copy machine  100  is charged, how to pay for it is decided through negotiation on the telephone. The APU  18  charges based on a set charging rate decided through negotiation, so that the charge reflects the result of negotiation.  
         [0140]     The control of the “negotiation operation” is performed by adding processes as follows. That is, the liquid-crystal touch panel  16  displays an entry screen for setting operation conditions based on the result of negotiation, and accepts a setting operation entered through the entry screen. The system controller  10  stores the set data confirmed by the operation of the “confirm button” in the RAM( 1 )  11 .  
         [0141]     The negotiation process by the copy machine configured in the above manner is explained below.  FIG. 11  is a flowchart of the negotiation process.  
         [0142]     At first, the user A and the user B, that are about to transmit and receive image data, are talking on the telephone using the telephone set  71   a  and the telephone set  71   b,  and negotiate about a value of an set item that requires negotiation on the telephone, to decide on the value. The negotiation and acceptance of the value of the set item by the telephone set  71   a  and the telephone set  71   b  may be performed after the set item is displayed. The copy machine  100   a  displays the set item on the liquid-crystal touch panel  16  (step S 1101 ). More specifically, the set item includes those such as a payment rate if the use of the copy machine  100  is charged and selection of the copy machine  100  to which image data is transmitted if a plurality of copy machines  100  used by users are connected to each other.  
         [0143]     The copy machine  100   a  accepts an input of the value of the set item (step S 1102 ). For example, if the set item is the payment rate which is made for use of each copy machine, then the result of negotiation with the user B is entered. If the set item is selection of a target of image data transmission, the target selected is entered by the user A. The copy machine  100   a  stores the values of the set items entered in the memory (step S 1103 ).  
         [0144]     When the copy machines are connected to the system, whether to transmit image information to the respective copy machines can be set at a time, thereby reducing a load of operation performed by the user. Moreover, the result of negotiation on a charging rate on the copy machine performed on the telephone can be instantly reflected in the system, thereby reducing a load of post-operation required after the task is finished.  
         [0145]     The “disconnect operation” is an operation such that when the copy machine  100  does not transmit and receive image information to and from a copy machine of the other party for a predetermined time or more, the copy machine  100  disconnects the connection based on determination by the copy machine  100  itself. This operation is executed to protect the machines themselves when the copy machines are left in a status of being connected to each other and yet not performing transmission and reception.  
         [0146]     The “disconnect operation” according to the first embodiment employs such a way that the connection is not instantly disconnected after a predetermined time has elapsed since connection is established between the copy machines, but that two steps are provided before the connection is actually disconnected in such a manner that each step is made to shift to the next step after a predetermined time has elapsed.  
         [0147]     More specifically, at the first step, when the copy machine does not transmit or receive image information to or from the copy machine  100  used by the other party for a predetermined time, the system controller  10  displays a message for confirming intension of the user to continue the connection on the liquid-crystal touch panel  16 . If there is no response from the user although the message is displayed thereon, the comparison result of the passwords executed in the “compare operation” is invalidated. Consequently, in order to restart transmission and reception of image information, it is necessary to enter passwords again and verify whether the passwords match each other.  
         [0148]     In this stage, the image information can be transmitted or received after the passwords are entered again and checked. However, the passwords are not entered again, and further, if the image information are not transmitted or received to or from a copy machine connected thereto for a predetermined time, the system controller  10  displays a message indicating “disconnection of the connection” on the liquid-crystal touch panel  16 . If there is no response from the user although the message is displayed thereon, the connection is actually disconnected, to finish “disconnect operation”.  
         [0149]     The disconnect process by the two copy machines  100   a  and  100   b  each configured in the above manner is explained below.  FIG. 12A  and  FIG. 12B  are flowcharts of the disconnect processes.  
         [0150]     The copy machine  100   a  determines whether a predetermined time has elapsed from the time when “match” has been stored in the comparison result storage unit as the comparison result (step S 1201 ). If it is determined that the predetermined time has not elapsed (“NO” at step S 1201 ), then the process returns to step S 1201 . If it is determined that the predetermined time has elapsed (“YES” at step S 1201 ), the copy machine  100   a  stores “non-match” as the comparison result of the passwords (step S 1202 ).  
         [0151]     The copy machine  100   a  transmits “invalidation” of the comparison result of the passwords (step S 1203 ). The copy machine  100   b  receives the “invalidation” of the comparison result of the passwords from the copy machine  100   a  (step S 1204 ). The copy machine  100   b  stores “non-match” as the comparison result of the passwords (step S 1205 ). The copy machine  100   b  transmits “invalidation” of the comparison result of the passwords (step S 1206 ).  
         [0152]     The copy machine  100   a  receives the “invalidation” of the comparison result of the passwords transmitted from copy machine  100   b  (step S 1207 ). The copy machine  100   a  displays the “invalidation” on the liquid-crystal touch panel  16  (step S 1208 ). The copy machine  100   b  also displays the “invalidation” on the liquid-crystal touch panel  16  (step S 1209 ).  
         [0153]     The copy machine  100   a  determines whether a predetermined time has elapsed from the time when “non-match” as the comparison result has been stored in the comparison result storage unit (step S 1210 ). If it is determined that the predetermined time has not elapsed (“NO” at step S 1210 ), then the copy machine  100   a  determines whether “compare operation” is performed (step S 1211 ). If it is determined that the “compare operation” is performed (“YES” at step S 1211 ), then the copy machine  100   a  performs the compare process. If it is determined that the “compare operation” is not performed (“NO” at step S 1211 ), the process returns to step S 1210 .  
         [0154]     At step S 1210 , if it is determined that the predetermined time has elapsed (“YES” at step S 1210 ), the copy machine  100   a  transmits a channel disconnection request signal to the copy machine  100   b , and requires the disconnection (step S 1212 ). The copy machine  100   b  receives the channel disconnection request signal (step S 1213 ). The copy machine  100   b  transmits a channel disconnection permission signal to permit the disconnection (step S 1214 ). The copy machine  100   a  receives the channel disconnection permission signal (step S 1215 ).  
         [0155]     When the channel is disconnected, the user information may be deleted from the server  200 .  
         [0156]     The mechanism of disconnecting the connection in two stages is provided in the “disconnect operation” whenever a predetermined time has elapsed. Thus, it is prevented that the copy machines are left connected, so that the copy machines will never be left connected when the users finish the business and the telephones are disconnected. Furthermore, the copy machine, which is failed to be disconnected, can be protected from unauthorized use by a malicious person. Moreover, since the connection is disconnected step by step, if the time when the copy machines are left connected is comparatively short, the process for restarting text transmission or reception can be simplified.  
         [0157]     The “scan to memory operation”, “Memory to Print operation”, “memory to network operation”, “network to memory operation”, “find operation”, “compare operation”, “negotiation operation”, and “disconnect operation” are respectively shown as basic operations of the copy machine  100 . However, only one of them may be executed or a combination of a plurality of the basic operations may be executed.  
         [0158]     In the latter case, each timing at which the user performs various settings through the liquid-crystal touch panel  16  is not necessarily set during interval between the basic operations. The settings may be collectively performed at arbitrary timing. The reason is that the contents of the settings are stored in either one of the RAM( 1 )  11  and the RAM( 2 )  21 , and the system controller  10  can read the contents at any time.  
         [0159]     The “copy machine-to-copy machine” function in the data transmission/reception system that includes the copy machine  100  ( FIG. 1 ) and a server  200  is explained below.  
         [0160]      FIG. 13  is a diagram for explaining one example of a data transmission/reception system according to a second embodiment of the present invention. In the second embodiment, only three copy machines and one server  200  are connected to the IP network  50 , for simplicity of explanation. The copy machines are called “copy machine  100   a”, “ copy machine  100   b”,  and “copy machine  100   c”,  and user names of the copy machines are called “A”, “B”, and “C”, respectively. IP addresses of the “copy machine  100   a ”, the “copy machine  100   b ”, and the “copy machine  100   c”  are set as “IP address A”, “IP address B”, and “IP address C”, respectively.  
         [0161]     In the second embodiment, it is assumed that the users “A”, “B”, and “C” of the copy machines can talk on the telephone, and hence, the users have the telephone sets  71   a,    71   b,  and  71   c  through a telephone line  70 , respectively.  
         [0162]     The operation such that each of the users provides a user&#39;s telephone number and a called party&#39;s telephone number to the respective copy machines  100   a  to  100   c  is called “to check in”. More specifically, this operation indicates an operation of manually entering a user&#39;s telephone number and a called party&#39;s telephone number through the liquid-crystal touch panel  16 . Alternatively, this operation indicates an operation of transmitting a user&#39;s telephone number and a called party&#39;s telephone number using wireless communication from the telephone sets  71   a,    71   b,  and  71   c  respectively provided near the copy machines  100   a  to  100   c,  to the TIFU  17  provided on each copy machine side (see the explanation of “find operation”). The operation of disconnecting the connection among the copy machines  100   a  to  100   c  with the intention of a user is called “to check out”. More specifically, a user tells the intention to disconnect the connection using the liquid-crystal touch panel  16  to the users, and the copy machines  100   a  to  100   c  disconnect the connection according to the instruction.  
         [0163]     The situation that requires the “copy machine-to-copy machine” function includes a situation such that “A” has to deliver a copy of a paper document to “B” when “A” and “B” are talking on the telephone. At this time, “A” tells “B” on the telephone that “A” wants to deliver the paper document.  
         [0164]     Then, “A” checks in the copy machine  100   a , and “B” checks in the copy machine  100   b.  The copy machine  100   a  and the copy machine  100   b  send IP addresses of their own machines, respective user&#39;s telephone numbers, and called party&#39;s telephone numbers to the server  200  by the “find operation”, and acquire destination information as the search result of the other party from the server  200 . In this example, the copy machine  100   a  acquires the IP address B, and the copy machine  100   b  acquires the IP address A.  
         [0165]     The copy machine  100   a  and the copy machine  100   b  finish the “find operation”, and start the “compare operation”. “A” talks to “B” on the telephone so as to decide on a mutual password. “A” and “B” enter the password in the copy machine  100   a  and the copy machine  100   b,  respectively. Then, the copy machine  100   a  and the copy machine  100   b  exchange the passwords to verify whether the passwords match each other. If it is verified that there is a match, the copy machine  100   a  and the copy machine  100   b  finish the “compare operation”, so that image information is ready to be transmitted and received between these machines.  
         [0166]     Thereafter, “A” sets the paper document on the document table of the copy machine  100   a , to instruct the copy machine  100   a  to read the paper document. And the “negotiation operation” is started, and “A” performs main settings of the “copy machine-to-copy machine” function. At this time, if there are some items to be decided by talking with “B”, such as how to pay for the fee for use charged, then “A” performs the settings based on the contents decided.  
         [0167]     After all the set items are decided and the “negotiation operation” is finished, the “scan to memory operation” and the “memory to network operation” are sequentially executed, and the paper document read is sent as a digital image to the copy machine  100   b.  When receiving the digital image, the copy machine  100   b  performs the “network to memory operation” and the “Memory to Print operation”, and the copy of the paper document is printed on the paper. By performing the operations, “A” and “B” have the paper documents of the same contents in hand.  
         [0168]     Thereafter, “A” and “B” continue talking about the contents of the paper document, and find out a point that both of them do not understand. Therefore, “A” and “B” decide to ask a question to “C”. “A” makes a call to “C” and tells about what the question is (hereinafter, talking among three parties), but the content of the question cannot sufficiently be delivered to “C” only by verbal explanation. Therefore, “A” decides to send the copy of the paper document to “C”.  
         [0169]     “C” checks in the copy machine  100   c.  Then, the copy machine  100   c  transmits the IP address of its own machine, the user&#39;s telephone number, and the called party&#39;s telephone number to the server  200 , and acquires destination information as the search result from the server  200 . More specifically, the copy machine  100   c  acquires the IP address A and the IP address B. The server  200  transmits the IP address C to the copy machine  100   a  and the copy machine  100   b  based on the search result. The copy machine  100   c  finishes the “find operation”, and then starts the “compare operation”. More specifically, “A” tells the password to “C”, and “C” enters the password into the copy machine  100   c.  When it is verified that there is a match between the passwords, the copy machine  100   c  finishes the “Compare operation”, so that image information is ready to be transmitted and received between the copy machine  100   a  and the copy machine  100   c.    
         [0170]     However, since the topic about which “A”, “B”, and “C” are talking on the telephone shifts to another topic, “A” fails to immediately send the paper document to “C”, and the three users continue talking for a long time. The copy machine  100   a,  the copy machine  100   b,  and the copy machine  100   c  are resulted in being left connected for a long time. Consequently, the respective machines start the “disconnect operation” to invalidate the comparison result of the passwords. Thereafter, “A”, “B”, and “C” notice the disconnection, and respectively enter again the passwords. As a result, the “compare operation” is performed again between the machines, so that the image information is ready to be transmitted and received among the machines.  
         [0171]     Thereafter, “A” executes transmission of the paper document to “C”. “A” sets the paper document on the document table of the copy machine  100   a , to instruct the copy machine  100   a  to read the paper document. And the “negotiation operation” is started, and “A” performs main settings of the “copy machine-to-copy machine” function. At this time, if there are some items to be decided by talking with “B” and “C”, such as how to pay for the fee for use charged, then “A” performs the settings based on the contents decided. In this case, in particular, “A” has transmitted the document to “B”, and hence, “A” transmits the paper document only to “C”. Therefore, even if transmission is possible to the copy machines “B” and “C”, it is necessary to perform setting so as to transmit the document only to “C”.  
         [0172]     After all the set items are decided and the “negotiation operation” is finished, the “scan to memory operation” and the “memory to network operation” are sequentially executed, and the paper document read is sent as a digital image to the copy machine  100   c.  When receiving the digital image, the copy machine  100   c  performs the “network to memory operation” and the “Memory to Print operation”, and the copy of the paper document obtained by “A” is printed on the paper.  
         [0173]     In this manner, “B” and “C” have the paper documents of the same contents as that obtained by “A”. Conversation is continued while they are looking at the paper document, and when the conversation ends, “A”, “B”, and “C” put down their telephone sets, and check out from the copy machine  100   a,  the copy machine  100   b,  and the copy machine  100   c,  respectively.  
         [0174]     Another example of the data transmission/reception system (see  FIG. 13 ) including “CTI compatible copy machines” according to the second embodiment is shown below. It is noted that the CTI stands for copier telephony Integration and means that the function is implemented by incorporating between the telephone and the copy machine. The function includes a function of checking telephone records of a user and searching for a copy machine as the other party when image information is transmitted and received through the IP network  50  between the copy machine and another copy machine. The “CTI compatible copy machine” performs “check in/out” operation by the TIFU  17  as shown in the another example.  
         [0175]     The data transmission/reception system according to the second embodiment is intended to be a system that effectively functions corresponding to the following situation.  
         [0176]     More specifically, assume such a scene that a business person notices that he(she) forgets bringing a material to be distributed to a client on the way to the client. If he goes back to the office to take it with him, he cannot arrive at an appointed place in time. Even in such a case, by executing the following procedure if both a copy machine installed in a convenience store and a copy machine installed in the office support CTI, this case can be solved.  
         [0177]     At first, the business person makes a call from his cell phone to the office to tell a staff in the office that he has failed to take the material with him. Then, the staff goes to the place where the material is stored to search for it. The telephone can be disconnected while the staff is searching for the material. In the meantime, the business person goes into a nearby convenience store.  
         [0178]     Thereafter, the staff finds out the material, and makes a call to the business person on his (her) cell phone to restart talking. Then, the staff checks in the copy machine in the office and the business person checks in the copy machine in the convenience store. In other words, both the copy machine in the office and the copy machine in the convenience store are “CTI compatible copy machines”, which constitute the data transmission/reception system according to the second embodiment.  
         [0179]     When the check-in is complete, they decide on a password during talking on the telephone, and enter the password into the respective copy machines. Thereafter, when the copy machines are ready to communicate with each other, the staff in the office scans the material using the “copy machine-to-copy machine” function, and the copy of the document is output from the copy machine in the convenience store.  
         [0180]     The data transmission/reception system according to the second embodiment is intended to be a system that effectively functions corresponding to the following situation.  
         [0181]     More specifically, assume such a scene that the CTI compatible copy machine is installed in a call center. The call center indicates a department of a company that deals with inquiries from customers by telephone. Any customer that calls the call center is supposed to have some desire to learn more details of the contents of the products and the services provided by the company. Therefore, when a staff in the call center answers the telephone, the staff is required for explanation sufficient enough for the customer to fully understand. However, since the staff explains only by oral on the telephone, satisfactory information cannot be given to the customer. This results in inadequate responses to the customers in many cases. Consequently, the customer may erroneously interpret the contents or forget the contents, which may lead to some trouble afterwards. Since the quality of the call center largely affects improvement of customer satisfaction (CF), increasing the quality is necessary. If the explanation can be given to the customers not only by oral but also using a drawing and a material, this helps the customers deepen their understanding of the products and the services, which makes it possible to surely deliver the information to the customers.  
         [0182]     If the “CTI compatible copy machines” are installed in both the call center and the home of the customer, this problem can be solved in the following manner. At first, the customer calls the call center, and starts talking to the staff on the telephone. Then, the customer checks in the copy machine in the customer&#39;s home, and the staff checks in the copy machine in the call center. They decide on a password through the telephone and enter the password into the respective copy machines.  
         [0183]     Thereafter, when the copy machines are ready to perform communications, the staff responds to an inquiry from the customer. If transaction of a paper document is necessary during phone inquiry, the sender of a document scans the document using the “copy machine-to-copy machine” function, and the copy of the document is output from the copy machine of the other party.  
         [0184]     For example, if there is an inquiry from the customer about an operation of home electronic appliances, the manual can be transferred from the staff to the customer. If there is an inquiry about how to take medicine, the staff can deliver the material including cautions to the customer. Because the customer has the paper document in hand, the contents explained by the staff can be repeated by the customer, thereby reliably delivering the information.  
         [0185]     Furthermore, the data transmission/reception system according to the second embodiment is intended to be a system that effectively functions corresponding to the following situation.  
         [0186]     More specifically, assume such a scene that a business person is traveling abroad. A scheduled meeting in an appointed place is cancelled on that date, which allows him (her) time to spend one day there. He plans to see the sights of the town where he stays, but he has no travel guidebook or so because this is not expected. Since there are a few bookstores abroad which sell books in Japanese, it is difficult to gain the travel guidebook there.  
         [0187]     In such a case, if both a copy machine installed in a hotel where he stays and a copy machine in his home or in a convenience store in his home country (Japan in this case) are the “CTI compatible copy machines”, then the problem can be solved in the following manner.  
         [0188]     At first, the business person makes a call from his cell phone to his family at home, and tells his family that he wants tour information for the town where he stays. Then, his family goes to a nearby bookstore to look for a tour guidebook. The telephone may be disconnected while his family is looking for the guidebook.  
         [0189]     When finding out and buying the guidebook at the bookstore, his family restarts talking to him on the telephone, to tell him that the guidebook is obtained, and checks in the copy machine in his home or in the convenience store. The business person also checks in a copy machine in the hotel. When the check-in is complete in both sides, they decide on a password through the telephone, and enter the password into the respective copy machines.  
         [0190]     Thereafter, when the copy machines are ready to perform communications, his family scans the guidebook using the “copy machine-to-copy machine” function, and the copy of the guidebook is printed out from the copy machine in the hotel where he stays.  
         [0191]     As shown in the second embodiment, if the “CTI compatible copy machines” are installed, then the “copy machine-to-copy machine” function works as if it is an application with an expanded telephone function.  
         [0192]     This is because when the copy machines  100   a  to  100   c  are to be connected to each other through the IP network  50 , a copy machine as the other party is automatically found out from the telephone records of the telephone sets  71   a  to  71   c  while the users do not need to be conscious of information specific to the copy machines  100   a  to  100   c,  being information processing terminals, such as IP addresses and MAC addresses.  
         [0193]     Since cell phones are widely used in recent years, even if a user does not know where a person, to whom image data is to be sent, is preset and the user cannot send it to the person, the user contacts him by cell phone, finds out a CTI compatible copy machine, and checks in the CTI compatible copy machine, so that the image information can be transmitted and received between the two.  
         [0194]     Although the copy machine connected to the communication network is mainly explained in the embodiments, if a transmission side of image data is a scanner that can acquire image data from a document and a reception side of the image data is a printer that can output the image data, the image data can be transmitted and received.  
         [0195]     Although the case where data to be transmitted and received is image data is explained in the embodiments, electronic data to be transmitted and received is not limited to the image data. Therefore, some other data such as moving picture data and speech data may be transmitted and received. The device used for transmitting and receiving the electronic data is not limited to office automation (OA) equipment such as the copy machine, the scanner, and the printer. Home electronic appliances, such as a DVD drive and a monitor connected to a network, may be connected to each other, thereby transmitting and receiving various data.  
         [0196]     In the embodiments, the case as follows is explained. That is, a user&#39;s telephone number and a called party&#39;s telephone number are transmitted from a user&#39;s telephone set to a copy machine, and the copy machine transmits its IP address to the server. Thereby, the user&#39;s telephone acquires an address of the copy machine used by the other party. However, in addition to this case, the following case may be included. That is, both copy machines may acquire IP addresses of their own machines in the following manner that a user&#39;s telephone set acquires an IP address of a copy machine, transmits the user&#39;s telephone number and the called party&#39;s telephone number together with the IP address acquired to the server. The user&#39;s telephone set acquires an IP address of a copy machine used by the other party, and transmits the IP address acquired to the copy machine. In this case, the telephone sets constitute the communication device according to the present invention.  
         [0197]     Although the invention has been described with respect to a specific embodiment for a complete and clear disclosure, the appended claims are not to be thus limited but are to be construed as embodying all modifications and alternative constructions that may occur to one skilled in the art that fairly fall within the basic teaching herein set forth.