Patent Publication Number: US-2004042029-A1

Title: Data communication device and method

Description:
BACKGROUND OF THE INVENTION  
       [0001] 1. Field of the Invention  
       [0002] The present invention relates to a data communication device and method, which can cope with occurrence of communication error adequately.  
       [0003] 2. Description of the Related Art  
       [0004] In conventional data communication, if an error occurred in the occasion of sending data, the data sent from the sender to the receiver was returned to the sender from the receiver with an error information. And, all the returned data was put out, that is, printed in paper or presented at display.  
       [0005] However, in this occasion, the returned data is what is sent from the sender to the sender itself. And, the sender knows the content of the returned data. So, this data was put out in vain. That is, for example, print papers were used in vain.  
       SUMMARY OF THE INVENTION  
       [0006] The present invention is made to solve the problem mentioned above and to provide means for coping with an error in data communication adequately. That is, a data sent from the sender and returned to the sender itself is a duplicate of a data offered by the user himself or herself. In considering this fact, an adequate solution for this occasion is offered. Therefore, present invention adopts following configuration.  
       [0007] &lt;Configuration 1&gt; 
       [0008] One is a data communication device comprising a data receiving section for receiving data, at least one data outputting section for putting out said data, an its own information detecting section for detecting information which indicates that the sender of said data is the sender, and a controlling section for limiting output of said data to said data outputting section when said its own information detecting section detected said information indicating that the sender of said data is the sender.  
       [0009] &lt;Configuration 2&gt; 
       [0010] The other is a data communication method for detecting information which indicates that the sender of said data is the sender, when an error information is detected from a received data; and limiting output of said received data according to the result of the detection. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0011]FIG. 1 is a block diagram showing a configuration of data communication device of Embodiment 1.  
     [0012]FIG. 2 shows an example of electronic mail content.  
     [0013]FIG. 3 is a flow-chart showing the operation of Embodiment 1.  
     [0014]FIG. 4 is a block diagram showing a configuration of data communication device of Embodiment 2.  
     [0015]FIG. 5 is a flow-chart showing the operation of Embodiment 2.  
     [0016]FIG. 6 is a block diagram showing a configuration of data communication device of Embodiment 3.  
     [0017]FIG. 7 is a flow-chart showing the operation of Embodiment 3.  
     [0018]FIG. 8 is a block diagram showing a configuration of data communication device of Embodiment 4.  
     [0019]FIG. 9 is a flow-chart showing the operation of Embodiment 4.  
     [0020]FIG. 10 shows an example of system structure.  
     [0021]FIG. 11 shows an example of normal electronic mail. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0022] Hereafter, the preferred embodiments according to present invention is described referring to the appended drawings.  
     [0023] &lt;Embodiment 1&gt; 
     [0024]FIG. 1 shows Embodiment 1 of data communication device of present invention.  
     [0025] The device shown in FIG. 1 comprises a controlling section  11 , an operating section  12 , a presenting section  13 , a reading section  14 , a printing section  15 , an image processing section  16 , and LAN controlling section  17 .  
     [0026] The controlling section  11  comprises a microprocessor  11   a  and a main memory  11   b . The microprocessor  11   a  is a processor for performing an over-all control of the data communication device. The main memory  11   b  is a memory comprising semiconductor etc. In this main memory  11   b  reserved is a program containing region  11   b . In this program containing region  11   b  contained are softwares corresponding to communication functions of internet or LAN connected with the data communication device, or a driver for controlling the operation of printing section  15 . Together with these, in the main memory  11   b , contained are softwares corresponding to a sending information managing section  11   b   2 , an error detecting section  11   b   3  and an information of itself detecting section  11   b   4 ; which are features of present invention.  
     [0027] The sending information managing section  11   b   2  automatically attaches a sending information to an electronic mail, when the data communication device sends the electronic mail, so as to manage the electronic mail individually. This information is an individual information of the electronic mail. And, this is an ID (identification) which enables recognition of the electronic mail. In Embodiment 1, this information is made up of a mark of Message-Id. The content of this Message-Id can be whatever can manage individual electronic mails to send. However, the content must be what can distinguish Message-Id of other data communication devices. Therefore. Message-Id is made up of a combination of date, time and mail address.  
     [0028] This information is automatically attached to the sending electronic mail as its head information. Here, a content of the electronic mail, which is got back to the sender when an error occurred, is described.  
     [0029]FIG. 2 shows an example of such a content of an electronic mail.  
     [0030] The electronic mail shown in FIG. 2 contains an information  101 , which is added by a mail server. This information  101  contains a message for informing the sender that a communication error occurred, as well as the head information.  
     [0031] Succeeding to this information  101 , returned is the electronic mail including the head information and the attached file. In this occasion, the content of the electronic mail is all the same as what has ever sent by the sender itself And, in this occasion, Message-Id contained in the head information is, for example, an information  102  shown in FIG. 2. This Message-Id is restored in a region of main memory  11   b  not shown in the drawings or a disk device not shown in the drawings.  
     [0032] The error detecting section  11   b   3  in FIG. 1 analyzes the content of the received electronic mail. And, it judges whether the content is informing of the occurrence of error or not. That is, it judges whether the content is what is shown in FIG. 2. As a concrete judging method, adopted is a method of detecting a letter row of “error” contained in the part of information  101  or a letter row of “failure” contained in the part of head information.  
     [0033] The information of itself detecting section  11   b   4  analyzes the content of the received electronic mail. And, it judges whether the content is same as that of the electronic mail ever sent by the sender itself. That is, it judges whether the information  102  shown in FIG. 2 (Message-Id) corresponds with the information stored in the sender itself or not. By this, it is detected that an electronic mail, which comprises what nothing is done to what has ever sent by the sender itself, has returned to the sender.  
     [0034] Moreover, as the sections other than these, in the main memory  11   b , the working region of the microprocessor  11   a  is provided.  
     [0035] The operating section  12  comprises keyboard for the user to operate etc, so as to perform operating process such as data sending etc. according to the user&#39;s instruction.  
     [0036] The presenting section  13  comprises displaying device, so as to present operating situation of the user or communication result/communication record etc.  
     [0037] The reading section  14  comprises an image reader, so as to read the original image to send, in the occasion when the data communication device acts as an internet facsimile.  
     [0038] The printing section  15  comprises any kind of a printer, so as to print out the content of the received electronic mail.  
     [0039] The image processing section  16  performs image processing of encoding image, compressing the encoded image and expanding the compressed image data.  
     [0040] The LAN controlling section  17  is connected with LAN  18 , so as to perform connecting control of LAN or connecting control with the internet via LAN  18 .  
     [0041] LAN  18 .  
     [0042] &lt;Operation of Embodiment 1&gt; 
     [0043] Next, the operation of Embodiment 1 is described, referring to the flowchart of FIG. 3.  
     [0044] When the data communication device in FIG. 1 sends an electronic mail, as shown in FIG. 3( a ), at first, it reads the original image to send (S 100 ). Then, it stores the data (S 101 ). And, the control waits until reading is finished (S 102 ).  
     [0045] When the reading is finished, the data communication device attaches an ID to the data (S 103 ). And, it stores the ID (S 104 ). Then, it sends the data with the ID (S 15 ). And, the control waits until sending is finished (S 106 ).  
     [0046] When the data communication device in FIG. 1 received an electronic mail (S 110 ), as shown in FIG. 3( b ), it analyzes the error information (S 111 ). This analysis is done, as mentioned above, by searching a prescribed letter row of “error” or “failure” etc. in the information  101  in FIG. 2.  
     [0047] When an error is existing (S 112 ), the data communication device analyzes the head information (S 113 ). Then, it judges whether the content of received electronic mail is same as what it has ever sent by itself (S 114 ). That is, the sender of the mail is the sender. This judgement is done by judging whether the information  102  in FIG. 2 accords with Message-Id kept in itself or not, as mentioned before.  
     [0048] When the received electronic mail contains the sender&#39;s own information, that is, both Message-Ids accord with each other, performed is an after process for dealing this electronic mail, which informs the sender that the previously sent electronic mail was not received. In Embodiment 1, the content of received electronic mail is not printed in this after process. Thus, printing same content can be avoided, when the sender keeps the sent data.  
     [0049] Here, the sender&#39;s data communication device may confirm whether the sent data is really kept or not. And, if it is not kept, the sender&#39;s data communication device may keep the content of received mail.  
     [0050] As an example of the after process, the error information is stored (S 115 ), and the received mail is deleted (S 116 ).  
     [0051] On the other hand, when the mail is not sent from the sender itself, the content of mail is printed (S 117 ), because it is necessary for the sender to analyze the mail. An example of printed error mail is shown in FIG. 2 mentioned before. Here, the information  101  can be edited.  
     [0052] Further on the other hand, when no error exist (S 112 ), the received mail is printed (S 117 ). An example of printed mail is shown in FIG. 11. As shown in FIG. 11, the content of mail, which is normally received, does not contain a part of the information  101  shown in FIG. 2. Here, other parts shown in FIG. 2 are edited as shown in FIG. 11.  
     [0053] &lt;Effect of Embodiment 1&gt; 
     [0054] As mentioned above, according to Embodiment 1, useless printing can be excluded; because a sending information managing section  11   b   2  for attaching head information to the electronic mail, so as to manage it individually, an error detecting section  11   b   3  and an information of itself detecting section  11   b   4  for judging whether the received electronic mail is informing of an error of an electronic mail sent by the sender itself, are provided, and the received content is not printed at all when the judgement is affirmative.  
     [0055] The reason why the content is not printed at all is that what is necessary to find the file failed sending is not the content of text but Subject, sending date and time etc. which specify File and which are written in the error information.  
     [0056] &lt;Embodiment 2&gt; 
     [0057]FIG. 4 shows a data communication device of Embodiment 2 of present invention.  
     [0058] The device shown in FIG. 4 comprises a controlling section  21 , an operating section  12 , a presenting section  13 , a reading section  14 , a printing section  15 , an image processing section  16 , and a LAN controlling section  17 . The configuration of sections other than the controlling section  21  is same as what is described in Embodiment 1 mentioned before. So, the same symbols are given to the sections corresponding to the same sections in Embodiment 1.  
     [0059] The controlling section  21  comprises a microprocessor  21   a  and a main memory  21   b . The main memory  21   b  contains a text searching section  21   b   5 . This comprises a software for realizing a data communication device of Embodiment 2, together with a sending information managing section  21   b , an error detecting section  21   b   3  and an information of itself detecting section  21   b   4 . This software is executed read in the microprocessor  21   a  step by step.  
     [0060] The text searching section  21   b   5  is what searches the part of text  103 , which has been sent by this device itself, from the received data shown in FIG. 2. In concrete, it takes out a boundary information  104  from the head information, so as to recognize boundaries in the received data. Here, at first, the information  102  sent by this device itself, mentioned before, is detected, in order to know the position of head information. In the example shown in FIG. 2, “----=Next Part 000 0009 01C11D06.6FA94CAO” is a boundary information  104 . This is taken out, after Message-Id is detected. Then, boundary information  105 ,  106 , which comprise the same row of letters, are searched in the received data. In this occasion, there is a part of text between the first boundary information  105  and the second boundary information  106 .  
     [0061] And, the microprocessor  21   a  makes the printing section  15  print out the text  103  including the first boundary information  105  not including the second boundary information  106 , when it received an electronic mail informing of communication error, which is caused by the electronic mail ever sent by this device itself. For this purpose, the program containing region  21   b   1 , the sending information managing section  21   b   2 , the error detecting section  21   b   3  and the information of itself detecting section  21   b   4  are installed in the main memory  21   b  of controlling section  21 , as well as the text detecting section  21   b   5 . These can comprise the program containing region  11   b   1 , the sending information managing section  11   b   2 , the error detecting section  11   b   3  and the information of itself detecting section  11   b   4  in Embodiment 1. So, the same description is omitted.  
     [0062] &lt;Operation of Embodiment 2&gt; 
     [0063] Next, operation of Embodiment 2 is described, referring to the flow-chart of FIG. 5.  
     [0064] When the data communication device in FIG. 4 received an electronic mail; the microprocessor  21   a  of controlling section  21 , at first, judges whether the content of received electronic mail is an error information or not (S 201 ), as shown in FIG. 5. This judgement is done by searching a prescribed letter row in the information  100  of FIG. 2, as described in the description of configuration of Embodiment 1. When it is judged that the mail is an error information, the control proceeds to the next step S 202 . Otherwise, the electronic mail is printed (S 206 ).  
     [0065] On the other hand, at step S 202 , it is judged that the content of received electronic mail is what the sender itself has ever sent or not. This judgement is done by judging whether the information  102  of FIG. 2 accords with the letter row kept in the sender itself or not. When the content is the sender&#39;s information, the control proceeds to the next step S 203 . Otherwise, the electronic mail is printed (S 206 ), because it is conceived that analysis of the electronic mail is necessary.  
     [0066] On the other hand, at step S 203 , Message-Id is searched for. And, boundary information  105 ,  106 , which are same as the boundary information  104 , are searched for. Then, the part of text  103  is detected. And, at the succeeding step S 204 , only the part of information  100  shown in FIG. 2 is printed out by the printing section  15 .  
     [0067] Finally, at step S 205 , an after process of the electronic mail is performed. An example of the after process is to delete the received electronic mail from the memory or to store the result of receiving of error information in the memory etc.  
     [0068] Incidentally, in the flow-chart of FIG. 5 mentioned above, step S 201  and step S 202  can be replaced with each other, as a varied embodiment.  
     [0069] &lt;Effect of Embodiment 2&gt; 
     [0070] As described above, according to Embodiment 2, if the sender wants to know the content of text at once, only the content of the part of text can be printed. Therefore, useless printing of other part can be excluded. Since, a sending information managing section  21   b   2  for including an information used for managing each electronic mail individually, in the head information attached to the head information; an error detecting section  21   b   3  and an information of itself detecting section  21   b   4  for judging whether the received electronic mail is informing the sender of an communication error of the mail sent by the sender itself or not; and a text searching section  21   b   5  for searching the pat of text  103  of data sent by the sender itself, from the received mail.  
     [0071] &lt;Embodiment 3&gt; 
     [0072]FIG. 6 shows a data communication device of Embodiment 3 of present invention.  
     [0073] The device shown in FIG. 6 comprises a controlling section  31 , an operating section  12 , a presenting section  13 , a reading section  14 , a printing section  15 , an image processing section  16 , and a LAN controlling section  17 . The configuration of sections other than the controlling section  31  is same as what is described in Embodiment 1. So, the sections corresponding to those having same configuration are designated with the same symbols. And, the duplicating description is omitted.  
     [0074] The controlling section  31  comprises a microprocessor  31   a  and a main memory  31   b . The main memory  31   b  contains an attached file searching section  31   b   6 . This comprises a software for realizing a data communication device of Embodiment 3, together with a sending information managing section  31   b   2 , an error detecting section  31   b   3 , an information of itself detecting section  31   b   4  and a text searching section  31   b   5 . This software is read out step by step, being executed in the microprocessor  31   a.    
     [0075] The attached file searching section  31   b   6  is what searches the received data shown in FIG. 2 for the part of attached file sent by the sender itself. In concrete, the boundary information  104 , which is included in head information of data sent by the sender itself, for recognizing boundaries of data, is taken out by the attached file searching section  31   b . And, it searches the received data for the boundaries. Here, at first, the information  102  sent by the sender itself is found, in order to know the position of head information.  
     [0076] In the example shown in FIG. 2, “----=NextPart 000 0009 01C11D06.6FA94CA0” is the boundary information  104 . And, this is taken out, after finding Message-Id. Then, the received data is searched for boundary information  105 ,  106 , comprising the same letter row. In this occasion, two-boundary information  105 ,  106  are found. And, there is an attached file&#39;s part  107  next to the second boundary information  106 . And, the attached file searching section  31   b  searches the attached file&#39;s part  107  for the file name  108 . In concrete, the file name is extracted from the data field indicated by a letter row of “name=” written next to a letter row of “Content-Type”. In the example of FIG. 2, the file name is a letter row of “attachment001.tif”. Or, instead, a file name  108 ′ can be extracted from the data field indicated by “Content-Disposition:attachment;filename=”.  
     [0077] And, the microprocessor  31   a  receives an electronic mail informing of a communication error. When the error has been caused by the sender&#39;s own mail ever sent, the file name  108  is printed out as well as the information  100 , including the text  103  between the boundary information  105 ,  106 . For this purpose, a program containing region  31   b   1 , a sending information managing section  31   b   2 , an error detecting section  31   b   3 , an information of itself detecting section  31   b   4  and a text searching section  31   b   5  are stored in the main memory  31   b  of controlling section  31 , as well as the file searching section  31   b   6  mentioned above. These can comprise the program containing region  11   b   1 , sending information managing section  11   b   2 , error detecting section  11   b   3 , information of itself detecting section  11   b   4  in Embodiment 1, and the text searching section  21   b   5  in Embodiment 2. So, their descriptions are omitted, since they are same.  
     [0078] &lt;Operation of Embodiment 3&gt; 
     [0079] Next, operation of Embodiment 3 is described, referring to the flow-chart of FIG. 7.  
     [0080] When the data communication device of FIG. 6 received an electronic mail; at first, it judges whether the received mail is informing of an error or not (S 301 ) as shown in FIG. 7. This judgement is same as what is described in Embodiment 1. When it judged that it is informing of an error, the control proceeds to the next step S 302 . Otherwise, the mail is printed (S 308 ).  
     [0081] On the other hand, at step S 302 , the device judges whether the content of received mail is same as what has ever sent by this device itself. This judgement is same as what is mentioned before. If it is same as that of this device, the control proceeds to the next step S 303 . Otherwise, the mail is printed (S 308 ), because an analysis of the mail is necessary.  
     [0082] On the other hand, at step S 303 , the mail is searched for Message-Id. And, the mail is searched for boundary information  105 ,  106 , which are same as the boundary information  104 . Then, the part of text  103  is found. And, at the succeeding step S 304 , it is judged whether there are two boundary information  105 ,  106 . If there are not two, that is, there is only one; only the part of information  100  shown in FIG. 2, including text sent by this device, is printed out (S 307 ).  
     [0083] On the other hand, if there are two boundary information  105 ,  106 ; at step S 305 , the information  100  shown in FIG. 2 and the name of attached file are printed out.  
     [0084] Finally, at step S 306 , an after process of the electronic mail is performed. An example of the after process is to delete the received mail from the memory or to store the record of error received in the memory as mentioned before.  
     [0085] Incidentally, the flow-chart of FIG. 7 can be varied similarly as the flowchart of FIG. 5.  
     [0086] &lt;Effect of Embodiment 3&gt; 
     [0087] As described above, according to Embodiment 3, when an electronic mail attaching file is received, only the part of text and the name of attached file can be printed out. So, useless printing is excluded. Since, an attached file searching section  31   b   6 , which searches the mail for the part of text, and a text searching section  31   b   5 , which searches the mail for the name of attached file, are provided as well as a sending information managing section  31   b   2  for including management information of individual mail in head part of mail, and an error detecting section  31   b   3  and an information of itself detecting section  31   b   4  for judging whether the received mail is informing of an error caused by the mail ever sent by the sender itself  
     [0088] &lt;Embodiment 4&gt; 
     [0089]FIG. 8 shows a data communication device of Embodiment 4 of present invention.  
     [0090] The device shown in FIG. 8 comprises a controlling section  41 , an operating section  12 , a presenting section  13 , a reading section  14 , a printing section  15 , an image processing section  16 , and a LAN controlling section  17 . The configuration of sections other than the controlling section  41  is same as the corresponding sections of Embodiment 1. So, the same sections are designated with the same symbols. And, duplicating description is omitted.  
     [0091] The controlling section  41  comprises a microprocessor  41   a  and a main memory  41   b . The main memory  41   b  contains a decoding section  41   b   7 . This comprises a software for realizing the data communication device of Embodiment 4, together with a sending information managing section  41   b   2 , an error detecting section  41   b   3 , an information of itself detecting section  41   b   4 , a text searching section  41   b   5 , and an attached file searching section  41   b   6 . This software is executed by the microprocessor  41   a , reading it step by step.  
     [0092] The decoding section  41   b   7  is what decodes the encoded data of attached file&#39;s part  107  sent by this device itself and found in the received data shown in FIG. 2. In concrete, this decoding process is done, after confirming the recognized file format and encoding formula included in the head information of attached file sent by this device itself. In the example of FIG. 2, it is judged that the file format is tiff (tag image file format), referring to the data field indicated by a letter row of “Content-Type:” and that the encoding formula is Base  64 , referring to the data field indicated by a letter row of “Content-Transfer-Encoding” 
     [0093] And, the microprocessor  41   a  prints out a decoded image data together with its file name by the printing section  15  as well as the information  100  between the first boundary information  105  and the second boundary information  106 ; when it received an electronic mail informing of a communication error and the error was caused by a mail ever sent by this device itself. For this purpose, a program containing region  41   b   1 , the sending information managing section  41   b   2 , error detecting section  41   b   3 , information of itself detecting section  41   b   4 , text searching section  41   b   5 , and attached file searching section  41   b   6  are provided in the main memory  41   b  of controlling section  41 , together with the decoding section  41   b   7 . The configurations of these sections are same as those of the program containing region  11   b   1 , sending information managing section  11   b   2 , error detecting section  11   b   3 , information of itself detecting section  11   b   4  in Embodiment 1, the text searching section  21   b   5 , in Embodiment 2, and the file searching section  31   b   6  in Embodiment 3. So, the duplicating description is omitted.  
     [0094] &lt;Operation of Embodiment 4&gt; 
     [0095] Next, the operation of Embodiment 4 is described, referring to the flowchart of FIG. 9.  
     [0096] When the data communication device of FIG. 8 received an electronic mail; as shown in FIG. 9, at first, it judges whether the content of received mail is an error information or not (S 401 ). If it judged that it is an error information, the control proceeds to the next step S 402 . Otherwise, the electronic mail is printed (S 408 ).  
     [0097] On the other hand, at step S 402 , it is judged whether the content of received mail is the information ever sent by this device itself or not. If it is not the information of this device itself; the mail is printed (S 408 ), because it is necessary for the sender to analyze the mail.  
     [0098] Otherwise, that is, it is the information of this device itself; at step S 403 , Message-Id is searched for. And, boundary information  105 ,  106 , which are same as boundary information  104 , are searched for. Then, the part of text  103  is detected. And, at the succeeding step S 404 , it is judged whether there are two boundary information  105 ,  106 . If there is only one boundary information  105 ; only the part of information  100 , that includes the text sent by this device itself, is printed out by the printing section  15  (S 407 ).  
     [0099] On the other hand, if there are two boundary information  105 ,  106 ; at step S 405 , the part of information  100  shown in FIG. 2, the name of attached file  108 , and an image data decoded from the attached file, are printed out.  
     [0100] Finally, at step S 406 , an after process of electronic mail is performed. Examples of after process are, as mentioned before, to delete the received electronic mail from the memory or to store record of received error information etc.  
     [0101] Incidentally, in the flow-chart of FIG. 9 referred above, steps S 401  and S 402  can be replaced with each other. Moreover, printing of the name of attached file can be omitted, relying on the printing of decoded content of attached file.  
     [0102] &lt;Effect of Embodiment 4&gt; 
     [0103] As described above, according to Embodiment 4, useless printing can be excluded, as image data is decoded when it is printed. And, this is printed, occasionally with the part of text or the name of attached file. Since, a sending information managing section  41   b   2  for including management information in the head information of electronic mail, so as to manage the sent mails individually; an error detecting section  41   b   3  and an information of itself detecting section  41   b   4  for judging whether the received electronic mail is informing of an error caused by the mail ever sent by this device itself; a text searching section  41   b   5  and an attached file searching section  41   b   6  for searching the content of the received mail for the part of text  103  and the name  108  of attached file respectively; and a decoding section  41   b   7  for decoding the attached file; are provided.  
     [0104] &lt;Other Description of Embodiments 1 to 4&gt; 
     [0105]FIG. 10 shows an example of system where the data communication device of Embodiments 1 to 4 are provided.  
     [0106] In FIG. 10, a data communication device C 1  is connected with LAN or Internet. This device is able to send or receive electronic mails, via a mail server  1  with a personal computer PC 1  or via a mail server  2  with a personal computer PC 2 . Here, in FIG. 10, the data communication device intends to send PC 1  an electronic mail attached with a file. However, a certain communication error occurs. And, an electronic mail informing of the error is sent from a mail server to the data communication device C 1 . In this occasion, the data communication device C 1  automatically judges whether the error is caused by an electronic mail sent by this device itself or not. And, it controls the output, that is, it avoids printing the content of the received mail of error information, it prints only the part of text, or it prints the name of attached file or decoded content of the file.  
     [0107] &lt;Other Embodiments&gt; 
     [0108] As mentioned above, Embodiments 1 to 4 comprised individually. However, the present invention is not limited to this. And, it is realized by another Embodiment made up for selecting either of Embodiments 1 to 4. Moreover, in above Embodiments, the output control is processed for error mails. However, for normal electronic mails, the present invention can be used as well. That is, when a sender sent a mail to a receiver normally and the receiver send a mail including the original content sent by the sender to the sender in normal process; the content can be detected by the information of itself detecting section, so as to cancel the output, for example, printing the content at the sender.  
     [0109] In each Embodiment mentioned above, the sending information managing section  11   b   2 ,  21   b   2 ,  31   b   2 ,  41   b   2  is made up for attaching automatically an identification of this device&#39;s data, so as to send the data. However, the present invention is not limited to this. The sending information managing section  11   b   2  etc. can be omitted. That is, there can be a communication device which attaches an identification by itself to the sending data. Then, the function of this device avails the present invention. And, it is possible to omit the section. Moreover, the device of present invention is realized by a software. However, instead of this, ASIC can be used for realizing present invention by a hardware.  
     [0110] Further, in Embodiments mentioned above, the device printing the received data was described. However, present invention is not limited to this. It can be embodied in a device presenting the received data at a display. In this occasion, the content of presentation becomes easy to understand for the user.  
     [0111] Although, Embodiments mentioned above are described about electronic mail, the present invention can also be applied to data communication between computers such as personal computer, or data communication between facsimiles.