KR19990013846A - Communication terminal device with e-mail function and e-mail communication method - Google Patents

Abstract

Provided are a communication terminal device having an e-mail function and a program recording medium therefor that simplifies operations during e-mail transmission.

A function (S1) for registering a plurality of users with each network type, a function (S2) for registering a plurality of counterparts with each network type, a user sending an e-mail and When the network type is different from that of the other party, a function S6 is provided for processing the e-mail address for communication between heterogeneous networks. This simplifies the user's operation.

Further, it is determined whether or not the data to be transmitted is divided into a plurality of e-mails based on the table T7 in which the mail size is recorded for each network type. E-mail can be sent.

Description

Communication terminal device with e-mail function and e-mail communication method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication terminal device such as a facsimile device with an e-mail function, and more particularly, to a communication terminal device having an e-mail function for simplifying operations during e-mail transmission and a program recording medium thereof.

In recent years, a wide range of computer communication networks, which consist of connecting LANs or individual personal computers to communication circuits such as telephone lines, have become widespread. The computer communication network includes the Internet and a personal computer communication service network. In the personal computer communication service network, there are NIFTY-Serve (hereinafter referred to as “Nifty”), PC-VAN, and the like. In the following, each of these computer communication networks is referred to as a network type. Communication between heterogeneous networks with different network types is also possible.

In the case of using a computer communication network, there are a plurality of providers that provide services such as a connection to a computer communication network, rather than the user communicating directly with the other party, and the user uses a computer (server) owned by the provider. Will communicate. In a personal computer communication service network, a post that oversees a service exists and a user communicates through a post computer. When a user uses a computer communication network, he connects a line to an access point of a supplier or a post, and then performs a procedure called login because he is authenticated to be a contractor. To log in, input of a user name (user ID) and a password only known to the user is required. By this login, the own communication terminal device is logically connected to the computer communication network.

The content of the service is different, but here we are talking about e-mail on the Internet. The user sends the stored e-mail to the e-mail having a predetermined format for the data to be communicated. In the e-mail, an e-mail address (e-mail address) of the user to be sent and an e-mail address of the other party are described. These e-mail addresses contain information indicative of their respective suppliers. The e-mail is stored in the supplier's mailbox to which the other party's user contracts. The recipient counterpart user can take out the e-mail from this mailbox at an appropriate time. In addition, an e-mail address uses a user name (user ID) represented by a character string based on a domain name system (DNS) instead of an IP address represented only by a numerical value.

The advantages of the computer network include the use of a communication method with excellent error correction and the ability to communicate with distant parties simply by paying the communication costs to the nearest contract provider or access point. have.

On the other hand, conventionally, facsimile communication for communicating image data using a telephone line has been widespread, and a communication procedure and a communication system for this purpose have been established. Since the communication procedure and communication method of facsimile communication differ from computer communication networks, it is not possible to connect a conventional facsimile apparatus to a computer communication network. Therefore, the present applicant proposes a facsimile apparatus having an e-mail function having a function of converting image data into an e-mail format and communicating with the facsimile apparatus.

By the way, a facsimile apparatus is often used jointly in an office etc. besides individual use. When a fax machine equipped with an e-mail function is used in common, there are complicated users and various types of networks to be used. Therefore, each e-mail is sent, and each user calls the telephone of the contracted provider or access point. Login of the user to be transmitted is performed. Login requires input of a user name (user ID) and a password that only the user knows. In addition, since the address of the user to be sent and the address of the other party are described in the e-mail, it is also necessary to input these addresses. E-mail addresses on the Internet are cumbersome because they have many digits and include alphanumeric characters and symbols in addition to numbers.

And since the network types of the other parties are also various, for example, communication between heterogeneous networks, such as nifty from the internet and nifty from the internet, occurs. In this case, an operation for processing an e-mail address for heterogeneous network communication is required.

On the other hand, depending on the network type, there is a limit on the amount of data that can be transmitted by one e-mail (hereinafter referred to as allowable mail size). For this reason, an e-mail with a large amount of data, in other words, a large mail size may not be transmitted. In other words, an e-mail of a mail size exceeding the allowable mail size cannot be transmitted from a network having an unlimited mail size (or a large allowable mail size) to a limited (or small allowable mail size) network.

The same problem arises with communication terminal devices having e-mail functions that are not limited to facsimile devices.

It is therefore an object of the present invention to provide a communication terminal apparatus which solves the above problems and simplifies the operation during e-mail transmission.

It is also an object of the present invention to solve the above problems and to provide a communication terminal device having an e-mail function and a program recording medium thereof, which suitably determine an e-mail size of e-mail between heterogeneous networks.

In order to achieve the above object, the present invention provides a function of registering a plurality of users with each network type, a function of registering a plurality of counterparts with each network type, a user who transmits an e-mail, and the electronic device. When the network type of the mail is different from that of the other party, the e-mail address is processed for communication between heterogeneous networks.

In processing the address, a character string for communication between heterogeneous networks may be registered in advance, and the character string may be added to the other party's address depending on the network type.

In addition, the program recording medium includes a procedure of registering a plurality of users with each network type, a procedure of registering a plurality of parties with each network type, a user sending an e-mail, and a counterpart of the e-mail. When the network type is different from the network type, the computer records the procedure of processing the e-mail address for communication between heterogeneous networks.

On the other hand, the present invention determines whether to divide the data to be transmitted into a plurality of electronic mails based on a table storing mail sizes for each network type.

According to the allowable mail size of the network type on the sending side and the allowable mail size of the network side on the receiving side, the maximum mail size of the e-mail to be transmitted may be determined, and the e-mail may be divided so as not to exceed the maximum mail size described above.

The program recording medium records, in a computer readable manner, a procedure for determining whether to divide the data to be transmitted into a plurality of electronic mails based on a table storing mail sizes for each network type.

Fig. 1 is a flowchart of the operation of the facsimile apparatus showing the first embodiment of the present invention, (a) is the operation of registration, and (b) is the flowchart of the operation of e-mail transmission.

2 is a configuration diagram of various tables installed in the facsimile apparatus according to the present invention, (a) shows a user table, (b) a counterpart table, (c) a prefix table, and (d) shows an access table.

3 is a circuit configuration diagram of the facsimile apparatus according to the present invention.

4 is a configuration diagram in which a facsimile apparatus according to the present invention is connected to a computer communication network.

5 is a diagram showing a processed e-mail address according to the present invention, (a) is an address used for communication from the NIFTY-Serve to the Internet, and (b) is a CIS from the Nifty-Sub. Address (c) used for communication to a network, and (c), respectively, represent an address used for communication from a CIS to the Internet.

6 is a flowchart of the facsimile apparatus according to the second embodiment of the present invention, (a) is a division determination operation, and (b) is a flowchart showing the division operation.

7 is a configuration diagram of various tables installed in the facsimile apparatus according to the present invention, (a) shows a user table, (b) a counterpart table, and (c) shows a size table.

* Description of the symbols for the main parts of the drawings *

One… Main fisherman 2... Reader

3... Register 4... Display

5... Control unit 6. External memory reader

7... ROM (program recording medium) 8... RAM

9... Image memory 10... modem

11... NCU 12... Data modem

14... External storage media

S1... Step to register the user with the network type

S2.. Step of registering the other party with network type

S6... Processing the other address for heterogeneous network communication

T1... User table T2... Counterpart table

T3... Prefix table S11... Steps to enter a user

S12... Enter the other party

S13... Step S14 to obtain the maximum data size. Steps in Dummy Encode

S15... Step S16 of the division decision. Partial Send Step

T5... User table T6... Counterpart table

T7... Size table

EMBODIMENT OF THE INVENTION Hereinafter, 1st Embodiment of this invention is described in detail based on an accompanying drawing. In this embodiment, the communication terminal device is a facsimile device with an e-mail function having a G3, G4 facsimile communication function and an e-mail function. 1 shows the flow of operation of the present facsimile apparatus. That is, Fig. 1 (a) is a flow of registration operation for registering a user, counterpart, network type, and the like, and Fig. 1 (b) is a flow of transmission operation for sending an e-mail. 2 shows various tables installed in the facsimile apparatus. That is, Fig. 2A is a user table T1 for registering a user, Fig. 2B is a counterpart table T2 for registering a counterpart, and Fig. 2C is a character string for communication between heterogeneous networks. A prefix table T3 for registering a prefix, and FIG. 2 (d) is an access table T4 for registering a telephone number of a provider or an access point. 3 shows a circuit configuration of the present facsimile apparatus.

As shown in Fig. 3, the facsimile apparatus includes a main control unit 1, a reading unit 2, a recording unit 3, a display unit 4, an operation unit 5, an external memory reading unit 6, a ROM 7, RAM 8, image memory 9, modem 10, NCU 11, and data modem 12. As shown in FIG.

The main control unit (CPU) 1 controls each unit of hardware through the bus 13, and at the same time, software (program) such as encoding, decoding, image (TIFF) conversion, binary / text conversion, mail editing, automatic dial communication procedure, and the like. ) Can be executed. In addition, the program of the registration operation and the transmission operation according to the present invention can be executed.

The reading unit 2 can read an original with an imaging device such as a CCD and generate black and white two-value image data.

The recording unit 3 includes a printer in accordance with an electrophotographic method, and can record (print output) image data received by facsimile communication from another G3 or G4 facsimile apparatus or image data obtained by e-mail.

The display unit 4 is provided with an indicator such as an LCD display, and can display the operation state, image data, registration contents, operation instructions, and the like of the facsimile apparatus.

The operation unit 5 is provided with a ten key for inputting a number, a speed dial key for speed dial operation, a one touch key for one touch operation, various function keys, a start key, and the like. The function keys have functions such as setting a phone number, e-mail address registration mode, and selecting a communication method. Ten-keys, speed-dial keys, and one-touch keys also have character input functions such as alphabets.

The external memory reading unit 6 can read a program or the like recorded in an external storage medium (program storage medium) 14 such as a floppy disk or a CDROM. Therefore, the program executed in the main control unit can be provided from the external storage medium 14.

The ROM 7 is a program recording medium which stores a program executed by the main control unit for operating the facsimile apparatus.

The RAM 8 is composed of an SRAM, a flash memory, or the like. The RAM 8 stores temporary data generated during program execution, and stores various registered data in a table form. In addition, programs obtained from external memory can be memorized and executed.

The image memory 9 is made of DRAM and stores image data.

The modem 10 has a fax modem function and is used for facsimile communication of image data.

The network control unit (NCU) 11 can close and open the analog line.

The data modem 12 has a data modem function and is used when sending image data by e-mail. The data modem 12 is connected to an external telephone terminal of the NCU and is connected to a serial port of the external interface 15 by RS232C. In G4 communication, an ISDN line is connected via a DSU (data line termination device) (not shown).

Next, a program executed by the main control unit will be described.

In encoding and decoding, image data is encoded and decoded by a coding method such as MH, MR, MMR, or the like. Hereinafter, image data encoded according to these encoding methods will be referred to as image data in G3 format. The G3 format image data is stored in the image memory.

In image conversion, G3 format image data is converted into TIFF (Tagged File Format) image data used in a general computer at the time of transmission, and GTI format image data is converted from TIFF image data at the time of reception. In addition, TIFF is a format published by Adobe System Co., Ltd., and various CLASSes for dealing with two values of monochrome, multiple values of monochrome, and full color are defined. One of them, CLASS F, defines G3 format image data, which is image data of an original coded by an encoding method such as MH, MR, MMR, or the like. Therefore, by adding TIFF header information of CLASS F to the head of the G3 format image data, it can be converted into TIFF image data.

In binary text conversion, binary data is converted into text data at the time of transmission, and text data is converted into binary data at the time of reception. There are computers on the Internet that cannot handle e-mail of binary data. When binary data such as TIFF image data is transmitted so that an e-mail is reached to the other party reliably, it is converted into text data. Text data handled on the Internet is defined as a 7-bit code in RFC (Request For Comments) 822, a document issued by the Internet Engineering Task Force (IETF). In this example, the conversion is performed using MIME (Multipurpose Internet Mail Extensions) base 64. According to this, 6-bit binary data is replaced with one of 64 characters (uppercase and lowercase alphabets, numbers, +, and /). To be converted into text data. MIME is specified in RFC1521, etc.

In mail editing, mail header information is added to TIFF image data converted into text data at the time of transmission, edited in the residual mail format, mail header information is removed from the data in electronic mail format at reception, and converted into text data. Extract only TIFF image data. Since e-mail of the Internet is prescribed to add predetermined header information as management information of e-mail, "From: (user address)" and "To: at the beginning of TIFF image data converted into text data at the time of transmission. Add surrenders such as "(Relative address)", "Subject:". In the present invention, in the case of communication between heterogeneous networks, a prefix is added to the other party's address.

In the automatic dial, the telephone number data is sent to the NCU 11 or the modem 10 for signal transmission to the telephone number read from the table.

The program of the registration operation and the e-mail transmission operation of the present invention will be described later in detail.

Next, the configuration of the table will be described.

As shown in Fig. 2 (a), the user table T1 is made up of a code number for specifying each user jointly using the facsimile apparatus, the user ID and password of the user, and the network type used by the user. Therefore, when a user who wishes to send an e-mail from this enters a code number, a user ID, password, and network type are obtained.

As shown in Fig. 2B, the counterpart table T2 is composed of the counterpart name, the e-mail address of the counterpart, and the network type used by the counterpart. Therefore, when the name of the other party for transmitting the e-mail is input from this, the e-mail address and network type are obtained.

As shown in Fig. 2 (c), the prefix table T3 is composed of a FROM (sending side) network type, a TO (receiving side) network type, and a prefix. Therefore, the necessary prefix is obtained in the network type between the user who sends the e-mail and the counterpart of the e-mail.

As shown in Fig. 2 (d), the access table T4 is formed by telephone number and network type. Thus, the telephone number of the calling provider or access point is obtained by the network type used for transmission.

In each of the above tables, the user's personal name, the other party's shortcut number, the other party's one touch, the fax telephone number, the facsimile type, the supplier's name, and the like may be registered.

Next, the registration operation will be described using Fig. 1A.

When the registration mode is set by the function keys of the operation unit, the program of the registration operation is started, and the display unit and the operation unit can be used for the registration operation. At this time, in the present invention, the network type is registered in addition to the user ID and password of the user (S1). In addition to the counterpart address, the network type is also registered (S2). The network type is selected by presenting a plurality of candidates prepared in advance, but a new network type not included in the candidate may be registered. The data input by the registration operation is stored in the user table T1, the counterpart table T2, and the access table T4. The prefix table T3 can be prepared in advance for the candidates described above, but for the new network type, a new prefix having FROM and TO replaced for each of the existing network types is registered.

Next, an e-mail transmission operation will be described with reference to Fig. 1 (b).

When the e-mail transmission mode is set by the function key of the operation unit, the program of the e-mail transmission operation is started, and the display unit and the operation unit can be used for the e-mail transmission operation. The user who wants to send an e-mail inputs his / her code number (S3). The user ID, password, and network type are directly obtained from the user table T1. Namely, the network type Net1 on the transmitting side is determined. Next, the user inputs the name of the other party or operates the shortcut number key or the one touch key (S4). The e-mail address and network type are directly obtained from the partner table T2. Namely, the receiving network type Net2 is determined. Subsequently, when the start key of the operation unit is operated, e-mail editing is started by reading the original, accumulating to the image memory (G3 format image data), TIFF conversion, and MIME conversion (S5). At this time, if Net1 and Net2 are the same, it is not necessary to process the other party's address. If Net1 and Net2 are different, the main control unit 1 extracts the corresponding suffix from the prefix table T3 and adds it to the counterpart address (S6). For example, when transmitting from the nipple to the Internet, INET: is added to the head of the counterpart address.

Then, the telephone number of the provider or access point is read from the access table T4, and a signal is sent. The user ID and password are read from the user table T1 and logged in. The e-mail is then sent to the provider or access point.

As a specific example, as shown in Fig. 4, there are facsimile apparatuses 41, 42, and 43 having an e-mail function, and facsimile transmission and reception are possible through a telephone line. The facsimile apparatuses 41 and 42 are connected to the Internet 46 via the servers 44 and 45, and the facsimile apparatuses 41 and 43 are the personal computer communication service network 47. Is connected to. 44a, 45a, 47a are mailboxes. The facsimile apparatus 41 is made available to the user (A) and (B). The user A can access the Internet 46 that is contracted with the server 44. The user B subscribes to the personal computer communication service network 47. Therefore, when the user A transmits the image data by e-mail to the facsimile apparatus 43, or when the user B transmits the image data by e-mail to the facsimile apparatus 42, as described so far, Since the network type between the user and the counterpart is different, the prefix is added to the counterpart address.

5 shows an example of an address to which a prefix is added.

The address in Fig. 5 (a) is used for communication from the naughty to the Internet. The address in Fig. 5 (b) is used for communication from the Naughty to the CIS. The address in Fig. 5C is used for communication from the CIS to the Internet.

A second embodiment of the present invention will be described below with reference to the accompanying drawings. In addition, description is abbreviate | omitted about the part same as 1st Example.

In this embodiment, the communication terminal device is a facsimile device having a G3, G4 facsimile communication function and an e-mail function. 6 shows the flow of operation of the present facsimile apparatus. 7 shows various tables installed in the facsimile apparatus. That is, Fig. 7A is a user table T5 for registering a user, Fig. 7B is a counterpart table T6 for registering a counterpart, and Fig. 7C is a size table for registering an allowed mail size. (T7).

Next, the configuration of the table will be described.

As shown in Fig. 7 (a), the user table T5 consists of a code number specifying each user jointly using the facsimile apparatus, a user ID and password of the user, and a network type used by the user. Therefore, when a user who wishes to send an e-mail from this enters a code number, a user ID, password, and network type are obtained.

As shown in Fig. 7 (b), the counterpart table T6 is formed of the counterpart name, the e-mail address of the counterpart, and the network type used by the counterpart. Therefore, when the name of the other party to send an e-mail is input from this, an e-mail address and a network type are obtained.

As shown in Fig. 7C, the size table T7 is composed of the sending network type, the receiving network type, and the maximum data size. In the maximum data size, one having a smaller allowable data size for the transmission and reception network types is registered. The maximum data size is obtained from the network type of the user who sends the e-mail and the counterpart of the e-mail.

In each of the above tables, the user's personal name, the other party's shortcut number, the other party's one touch, the fax telephone number, the facsimile type, the supplier's name, etc. may be registered together.

Next, an e-mail sending operation including a division determination operation and a division operation will be described with reference to FIG.

When the e-mail transmission mode is set by the function keys of the operation unit, the program of the e-mail transmission operation is started, and the display unit and the operation unit can be used for the e-mail transmission operation. As shown in Fig. 6A, a user who wants to send an e-mail inputs his or her code number (S11). The user ID, password and network type are directly obtained from the user table T5. Namely, the network type Net1 on the transmitting side is determined. Next, the user inputs the other party's name or operates the shortcut number key or the one touch key (S12). From the counterpart table T6, an e-mail address and a network type are directly obtained. That is, the receiving network type Net2 is determined. By referring to the size table T7 by the combination of Net1 and Net2, the maximum data size in the e-mail transmission from Net1 to Net2 is obtained (S13).

Then, when the start key on the control panel is operated (without the start key in the case of one touch), the document is read, stored in the image memory (G3 format image data), TIFF conversion, MIME conversion, e-mail editing, telephone number. Signal transmission, login, and e-mail transmission are performed.

In the process from reading the original to sending the electronic mail, as shown in Fig. 6B, first, dummy encoding S14 is performed. The dummy encoder converts the entire image data stored in the image memory by TIFF conversion and MIME conversion. The data size of the text data obtained by this MIME conversion is obtained. The division determination S15 program determines whether to divide the data to be transmitted into a plurality of electronic mails by using the data size of the text data and the maximum data size. If the data size is less than or equal to the maximum data size, it is not necessary to divide it. If the data size is larger than or equal to the maximum data size, it is divided. In the case of division, the data size is divided by the maximum data size, and the number of divisions is determined by rounding down the decimal point. For example, if the maximum data size is 160 KB and the data size is 470 KB, it is divided into three (up to S15 here). Therefore, the image data stored in the image memory is divided into three, for example, according to the number of divisions, and one division is formed by TIFF conversion and MIME conversion to form one e-mail. In this e-mail, division information such as 1/3, 2/3, 3/3 is sequentially written in the item of "Subject:" to indicate which item of which division is the e-mail. In this way, all the image data stored in the image memory is divided into e-mails and transmitted. In this way, after the image data of one original is transmitted by a plurality of divided or undivided emails, the user logs out (S16).

As a specific example, as shown in Fig. 4, there are facsimile apparatuses 41, 42, and 43 having an e-mail function, and mutual facsimile transmission is possible via a telephone line. The facsimile apparatuses 41 and 42 are connected to the Internet 46 via the servers 44 and 45, and the facsimile apparatuses 41 and 43 are the personal computer communication service network 47. Is connected to. 44a, 45a, 47a are mailboxes. The facsimile apparatus 41 is made available to the user (A) and (B). User A has a contract with server 44 and can access the Internet 46. The user B is subscribed to the personal computer communication service network 47. Here, when the user A transmits the image data by e-mail to the facsimile apparatus 43, or when the user B transmits the image data by e-mail to the facsimile apparatus 42, as described so far, Since the network type between the user and the counterpart is different, the facsimile apparatus 41 makes a division determination based on the size table T7.

As described above, in the present invention, even if there is a difference in the allowable mail size according to the network type, the electronic mail can be transmitted reliably. The e-mail split at this time determines the size of the e-mail registered in the table with reference to the network type obtained from the inputs of the user and the counterpart, thereby preventing unnecessary splitting. Unnecessary splitting means that when the maximum mail size is fixed based on a network type having a small allowable mail size, even when a network type having a large allowable mail size is used, the splitting is performed because the maximum mail size is fixed. In the present invention, it is determined whether to divide from the allowable mail sizes of the network type of the transmitting side and the receiving side, and the number of divisions is also determined, so that the data to be transmitted can be reliably transmitted with the minimum number of e-mails.

When the address is specified by direct input without using the user code number or the other party's name (shortcut number or one-touch), the network table is not divided because the user table T5 and the other party table T6 are not referenced. In the case of communication between heterogeneous networks, a suffix is added to the other party's address. Thus, the presence of this suffix determines communication between heterogeneous networks, and analyzes the suffix to determine the sender network type and the receiver network type. have. For example, if the sender side is the destination and INET: is added to the head of the mail address, it can be seen that the receiver side is the Internet. Therefore, the maximum data size can be obtained based on the size table T7. If the network type or allowable data size are not clear, the maximum data size may be adjusted to the smallest allowable data size.

In the above embodiment, the maximum data size is registered in the size table T7 corresponding to the sending network type and the receiving network type, and the maximum data size is determined based on the sending network type and the receiving network type. The allowable data size may be registered in the table for each network type, and the smaller allowable data size may be the maximum data size with reference to the allowable data size for each network type of the transmitting and receiving sides.

In addition, the present invention is not limited to a facsimile apparatus, and the above procedure can be recorded on a program recording medium and provided to a communication terminal apparatus having a computer.

The present invention exhibits the following excellent effects.

(1) Since the communication terminal apparatus determines whether or not communication between heterogeneous networks, the user does not need to be aware of the network type.

(2) In the communication between heterogeneous networks, the communication terminal apparatus processes the address, so that the user does not need to operate it, nor is it wrong.

(3) The mail size of the e-mail between heterogeneous networks can be determined appropriately so as to be able to communicate with the mail size and not excessively large.

(4) The user can transmit without being aware of the network type of the other party or the allowed mail size.

Claims (7)

When a function of registering a plurality of users with each network type, a function of registering a plurality of parties with each network type, and a network type between the user who sends an e-mail and the other party of the e-mail are different. A communication terminal device having an e-mail function, characterized by having a function of processing an e-mail address into a communication between heterogeneous networks. The communication terminal apparatus according to claim 1, wherein the processing of the address is performed by registering a character string for communication between heterogeneous networks in advance, and adding the character string to the counterpart address according to the network type. Registering a plurality of users with each network type, registering a plurality of parties with each network type, and when the network type between the user sending an e-mail and the other party of the e-mail is different. An e-mail communication method comprising the steps of processing an e-mail address for communication between heterogeneous networks. A communication terminal device having an e-mail function having a transmission means for transmitting an e-mail toward a network, wherein the data to be transmitted is divided into a plurality of e-mails based on a table storing mail sizes for each network type. And a judging means for judging a and a dividing means for dividing the transmission data into a plurality of e-mails when it is determined that they have been divided. 5. The method according to claim 4, wherein the dividing means divides the transmission data by the allowable mail size of the sending network type and the allowable mail size of the receiving network type so that the transmitted e-mail does not exceed the maximum mail size. Communication terminal device with an e-mail function, characterized in that. 5. A communication terminal apparatus with an e-mail function according to claim 4, further comprising means for including division information as e-mail as header information. Determining whether to divide the data to be transmitted into a plurality of e-mails based on a table storing the mail size for each network type; and when it is determined that the data is divided, the transmission data is divided into a plurality of e-mails. And transmitting the plurality of e-mails to a network.