KR100435501B1 - Method and system for transferring large quantity data - Google Patents

Abstract

The present invention provides a data transmission method and system capable of transmitting a large amount of data even when not online, and capable of receiving data only when a receiver desires it. The sender sends a large amount of data in the form of an e-mail or a file using a sending client. The receiver receives a large amount of data in the form of an e-mail or a file using a receiving client. Computers of the transmitting client and the receiving client are provided with a data transmitting Intelligent Mobile Agent (IMA) and a data receiving IMA for transmitting and receiving data, respectively. The data transmission IMA performs the process of creating, collecting, and maintaining the temporary ID and password of the receiver, the server list, the file list, and the time-limited attribute that defines the storage period of the file. The data transmission IMA transmits a file to be transmitted to a file server, and attaches a data reception IMA that can download the file to an e-mail. The receiving side performs a data download process from the selected online file server storing data among the file servers included in the server list based on the information on the transmission data included in the received data receiving IMA.

Description

Mass data transfer method and system {Method and system for transferring large quantity data}

The present invention relates to a large data transmission method and system, and more particularly, to a data transmission method and system that can not only transmit a large amount of data even when not online, but also receive data only when a receiver desires it.

With the development of the Internet, the amount of data transmission through the Internet is rapidly increasing. In particular, with the proliferation of multimedia, there are many cases in which a large multimedia file is transmitted, and the size of the transmitted file is gradually increasing.

To transmit data through the Internet, it is necessary to use an online transmission system such as peer-to-peer (P2P), file transfer protocol (FTP), messenger (Messenger), or electronic mail.

In the case of the online transmission system, since only authorized users can access data through a user authentication procedure, an unnecessary user can be prevented from connecting and unnecessary data can be prevented from being stored.

However, in the case of transmission using an online transmission system, there is a constraint that both the transmitting side and the receiving side must be connected in an online state. Since network communication environment is often disconnected, it often happens that either of the data is taken off line and the transmission is interrupted. In addition, even if you want to send data to someone, there is a disadvantage that can not be transmitted if the other party is not online.

On the other hand, there is an electronic mail system as a system that can transmit data even if the receiver is not online. The e-mail system does not have to be the sending client and the receiving mail server, or the sending client and the receiving client are online. When the sending client sends mail, the sending client and the sending mail server must be online, and when the sending mail server sends the mail to the receiving mail server, both must be online, and the receiving client is sent to the receiving mail server. When connecting and receiving mail, both parties need to be online. Thus, the user does not need to transmit data depending on the receiving server.

Email systems were originally designed for sending short messages. However, since a large file can be attached and sent using the file attachment function, data transmission using an e-mail system has been made a lot. However, in the case of the e-mail system, since the capacity of the e-mail is often limited by the mail server itself, it is often impossible to transmit a large amount of data. In addition, when the e-mail is sent, the receiving server receives the e-mail even if the receiver does not want to receive the e-mail, thereby causing unnecessary space. In addition, mail to unspecified number of recipients, such as spam mail, may threaten the stability of the mail server.

In order to solve this problem, a method of transmitting only a reference to a file has been proposed, rather than transmitting the file itself.

The e-mail system of US Pat. No. 5,771,355 stores the attached file in the local storage location of the sender when sending the e-mail, and transmits only the link attached to the e-mail. The location where the attachment is stored must be accessible on the network. The node receiving the e-mail then attaches it when the cost of sending the e-mail with the attachment attached locally is lower than the cost of sending only the e-mail message with the attachment attached locally. Copy the file locally.

On the other hand, the electronic mail system of U.S. Patent No. 5,903,723 also stores an attached file in a local storage location on the sending side when sending an email, and attaches only the link to the email. The location where the attachment is stored must be accessible on the network.

According to this method, not only the loading of the receiving mail server can be reduced, but also the unnecessary channel bandwidth occupancy due to the transmission of the attachment on the network can be reduced when the receiver does not receive the attachment.

However, there is a fear that an unauthorized person may access this file because the attachment is stored in a local storage place accessible from the network. Therefore, these systems allow you to encrypt attachments and send keys to decrypt them with e-mail to prevent unauthorized access to attachments stored in local storage accessible on the network. Doing.

However, this method has the disadvantage that the user must decrypt the file using the attached key in order to use the file. That is, the receiver is very inconvenient because it needs to read the attachment stored in the local storage, and then use the decryption tool to decrypt the password.

SUMMARY OF THE INVENTION The present invention has been made in view of this point, and an object of the present invention is to provide a large data transmission method and system capable of transmitting a file even when the receiving side is not online.

Another object of the present invention is to provide a large data transmission method and system that can transmit a file even when the receiving side is not online, but cannot be accessed by anyone other than a legitimate recipient.

Another object of the present invention is to provide a large data transmission method and system that can be easily downloaded and used by a legitimate recipient.

1 is a block diagram showing the configuration of a large-capacity data transmission system of the present invention.

2 is a view showing the overall flow of a large data transmission method according to the present invention using an email system.

3 is a flowchart showing the operation of the transmitting client in the mass data transmission method according to the present invention using the e-mail system.

4 is a flowchart showing operation in a data transmission IMA.

5 is a flowchart showing the operation of the receiving client in the mass data transmission method according to the present invention using the e-mail system.

6 is a flowchart showing operation in a data receiving IMA.

7 is a flowchart showing operations in a file server.

8 is a first modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system.

9 is a second modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system.

10 is a third modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system.

11 is a flowchart illustrating a process of uploading files to a plurality of file servers in a data transmission IMA.

12 is a flowchart illustrating a process of downloading files from a plurality of file servers in a data receiving IMA.

FIG. 13 is a flowchart illustrating an operation flow at a data transmission side as an example of combining a data transmission method according to the present invention with a P2P system.

FIG. 14 is a flowchart illustrating an operation flow at a data transmission side as an example of combining the data transmission method according to the present invention with an online file transfer system such as FTP.

The sender sends a large amount of data in the form of an e-mail or a file using a sending client. The receiver receives a large amount of data in the form of an e-mail or a file using a receiving client. Computers of the transmitting client and the receiving client are provided with a data transmitting Intelligent Mobile Agent (IMA) and a data receiving IMA for transmitting and receiving data, respectively. The data transmission IMA performs the process of creating, collecting, and maintaining the temporary ID and password of the receiver, the server list, the file list, and the time-limited attribute that defines the storage period of the file. The data transmission IMA transmits a file to be transmitted to a file server, and attaches a data reception IMA that can download the file to an e-mail. The receiving side performs a data download process from the selected online file server storing data among the file servers included in the server list based on the information on the transmission data included in the received data receiving IMA. File servers receive a large amount of files from the sending client and allow the receiving client to download them at the request of the receiving client. In addition, the file server automatically deletes a file after a certain time according to the time-limiting property of the stored file.

Hereinafter, a data transmission system according to the present invention will be described in detail with reference to the accompanying drawings.

1. System Configuration

The configuration of the mass data transmission system of the present invention is shown in FIG.

The user transmits a large amount of data in the form of an e-mail or a file by using the transmission client 100. The sender 100 is an email client or an online file transfer client.

The user receives a large amount of data in the form of an e-mail or a file using the receiving client 200. The receiving client 200 to download data includes an email client or an online file transfer client.

An intelligent mobile agent for transmitting and receiving data is installed in the computer of the transmitting client 100 and the receiving client 200. Hereinafter, the intelligent mobile agent installed on the transmitting client 100 side will be referred to as 'data transmission IMA', and the intelligent mobile agent installed on the receiving client 200 side will be referred to as 'data receiving IMA'.

The intelligent mobile agent is a file list including various information related to the transmission data, namely, a temporary ID and password of the receiver, a server list indicating the location of file servers to store the data, a data file name and a file location. The process of creating, collecting, and maintaining a time constraint attribute that defines the storage deadline of a file. The receiving client performs a data download process from the selected online file server storing data among the file servers included in the server list based on the information about the transmission data.

Data Transmission and Receipt The installation and execution of the IMA can optionally be performed in several ways.

That is, the data sending IMA may be installed and executed by the sending user, and the data receiving IMA may be combined with the mail to be transmitted, transferred from the sending client to the receiving side, and installed and executed. Alternatively, data transmission and reception IMAs may be preinstalled and executed on each of the transmitting client and the receiving client by the transmitting and receiving users. Alternatively, the mail server may combine both the transmission and reception functions of the data transfer mobile agent (IMA). This provides users with the transparency of the email system, while eliminating the need to modify the send / receive mail client and install it on the send / receive client. Alternatively, the mail server may be configured to combine or separate each of the mobile agent's sender function and the receiver function. Each of these details is mentioned later.

In the present invention, the file is transmitted using the e-mail system 300. The email system 300 in the present invention assumes a typical email system that professionally sends text messages. The e-mail system can be operated independently or integrally with the sender and the receiver. In the following description, a case where the transmitting and receiving sections are integrated is illustrated as an example, but the present invention is not limited thereto.

The file transfer system of the present invention may operate one or more online file servers 400a, ..., 400n on a network. The file servers 400a,..., 400n receive a large amount of files from the transmitting client 100 so that the receiving client 200 can download them at the request of the receiving client 200. In addition, the file servers 400a, ..., 400n automatically delete files after a predetermined time according to the time-limiting property of the stored files. The file servers 400a, ..., 400n may keep the same large data redundant. In addition, the file servers 400a, ..., 400n may each fail.

2. Data transmission linked to email system

Next, a method of transmitting data according to the method of the present invention in conjunction with an e-mail system will be described.

First, the overall flow of data transmission will be described with reference to FIG. 2. 2 is a view showing the overall flow of a large data transmission method according to the present invention using an email system.

When a user (sender) who wants to send data uses the sending client 100 to create an e-mail message and attaches a file to send, and selects an e-mail sending command, the sending client sends the data sending IMA installed on the sender's computer. Drive. In other words, create a sending client to automatically call the data sending IMA, or install a plug-in to an existing sending client such as Outlook to send an e-mail sending command to start the data sending IMA. Alternatively, the data transmission IMA can be driven from the time that the computer is turned on, that is, the data transmission IMA resides in the memory, so that the data transmission IMA can be automatically detected by detecting that the sending client sends the e-mail.

The data transmission IMA uploads the attached file to the file server 400 (S210), and sends the data receiving IMA including an ID and password for downloading the uploaded file and information on the attached file together with the e-mail message. Transmit to 300 (S220).

In FIG. 2, for convenience of description, the sender's email server and the receiver's email server are bundled and represented as an email system 300. In reality, when the sender sends a mail, the sender sends the mail from the sending email server to the receiving email server. However, the procedure is omitted in FIG.

When the receiver requests an e-mail by accessing the e-mail system 300 using the e-mail program installed in his computer, the e-mail program 300 (S230), the e-mail system 300 sends e-mail to the e-mail client 200. Transmit (S240). At this time, the e-mail includes not only a message written by the sender but also a data receiving IMA including an ID, a password for downloading the attached file, and information on the attached file.

When the recipient of the e-mail receives a file attached to the e-mail, the attached data receiving IMA is activated. Then, the data receiving IMA requests the file to the file server 400 in which the file is stored using the information on the attached file (S250). At this time, in order to prevent a person without file access authority from downloading a file, the data receiving IMA transmits the included ID and password to the file server 400.

The file server 400 receiving the file download request checks whether the received ID and password match the ID and password assigned to the file, and transmits the file to the receiving client 200 when the file ID is matched (S260). .

By the above procedure, the sender sends the file that the sender wants to send. The e-mail system takes less load because only the message and the data receiving IMA are transmitted, not the large file attachment. . In addition, since the receiving side can read only the e-mail message and receive only the data he / she wants, he can save time and e-mail receiving space.

Next, data transmission / reception procedures in the transmission client 100, the reception client 200, and the file server 400 will be described in detail. Since the e-mail system 300 may use the conventional e-mail system 300 as it is, a detailed description of the procedure in the e-mail system 300 will be omitted.

2-1. Data transmission algorithm

A process of creating and sending an e-mail using a general e-mail client program will be described with reference to FIG. 3. First, the user writes a message using the email client 100 and attaches a data file to be sent to create email data to be transmitted (S300). When the email is completed, the user executes a send (SEND) command of the email sending client 100 (S310). When the send command of the email sending client 100 is executed, the data sending IMA is automatically called (S320).

Next, the operation in the data transmission IMA will be described with reference to FIG. 4.

The data transmission IMA first determines whether the size of the attached file is larger than a predetermined allowable capacity (S400). The allowable capacity can be set by the user or can be set by the data sending IMA by contacting the email server. In addition, it is possible to determine whether the size of the entire e-mail including the attached file is larger than a predetermined allowable capacity, not the size of the attached file.

If the size of the e-mail is not larger than the predetermined allowable capacity, the data transmission IMA checks whether the file transmission through the file server is set (S410). Alternatively, it is possible to show a window asking the user if he or she wants to transfer a file through the file server and have it confirmed by the user. Alternatively, e-mails smaller than the allowable capacity may be sent using a normal e-mail transmission procedure without passing through a file server regardless of user settings.

If the size of the e-mail is not larger than a predetermined allowable capacity and the file transmission through the file server is not set, the e-mail is transmitted according to a normal e-mail transmission procedure (S470).

On the other hand, if the size of the e-mail is larger than the predetermined allowable capacity, or if the file transfer through the file server is set, upload the attachment to the file server 400 (S420). In this case, it is also possible to upload attachments to a plurality of file servers, which will be described later.

Meanwhile, when uploading an attached file, it is preferable that the data transmission IMA undergo a login process to the file server 400. That is, before uploading the attached file, the ID and password of the data transmission IMA are transmitted to the file server 400 to be authenticated, so that only the registered data transmission IMA can enable file transmission.

When uploading an attached file to the file server 400, in addition to the attached file, a temporary ID and password of the receiver, a file list indicating the path of the attached files, a time limit attribute defining a time limit for downloading the corresponding file, Upload together. In addition, when using a plurality of file servers, it is also possible to upload a server list indicating the address or server ID of the server that stores the attached file. In addition, in the case of transmitting a file to a plurality of recipients, IDs and passwords may be created and uploaded for each recipient.

The data transmission IMA also attaches the data reception IMA including the temporary ID and password of the recipient, the file list, the time limit attribute, and the server list to the e-mail (S430). Step S430 may be executed before step S420 or after file upload is successful in step S440.

If the attachment fails to upload to the file server 400 (No in S440), the user is asked whether to upload again (S450). Alternatively, it may be set to automatically retry until a certain number of times.

If the file upload fails even after retrying a predetermined number of times, or if the user does not want to retry, the user attaches the file attached to the e-mail created by the user (S460), and then sends the e-mail according to the normal e-mail transmission method. It is to be transmitted (S470).

If the file upload to the file server 400 is successful at step S440, the data receiving IMA is sent with the attached email (S470).

2-2. Data reception algorithm

A process of receiving a mail using a general email client program will be described with reference to FIG. 5.

If the receiving client 200, that is, the email program of the email user side is operated or the user selects an email receiving command (S500), the receiving client 200 accesses the email receiving server and undergoes a login process to retrieve the email (S510). . The user opens the received mail (S520) and checks whether the received email includes the data receiving IMA (S530). If the data receiving IMA is not included, since the general email is read (S550). If the data receiving IMA is included, the data receiving IMA is executed (S540). Alternatively, if the user opens an email containing the data receiving IMA instead of manually executing the data receiving IMA, the data receiving IMA may be automatically operated by the connected plug-in. Alternatively, you can configure the receiving client to open the email containing the data receiving IMA so that the receiving client automatically executes the data receiving IMA.

Next, the operation of the data receiving IMA will be described with reference to FIG. 6.

When the data receiving IMA is operated, the data receiving IMA first compares the current time and the time limit attribute included in the operation S600. If the timeout has elapsed, return to the main program that called the data receiving IMA.

When the timeout requirement is satisfied, the online file server 400 included in the attached server list is requested for data files included in the file list (S610). At this time, necessary information such as ID, password, file list is transmitted to the file server 400 by the data receiving IMA. If multiple online file servers are listed in the server list, the file may be requested from only one of them.

If the information such as ID, password, file list, etc. transmitted to the file server 400 is correct, the online file server 400 transmits the corresponding data files (S620). If the reception of all files is successful (YES in S630), the process returns to the email receiving client main program. If the data download fails (No in S630), it is checked whether to retry (S640).

The retry process means calling the mobile agent again. If you do not want to retry check whether you want to receive this data file again (S650). If you want to receive it later, the data receiving IMA marks the mail as unconfirmed mail and ends (S660). If you don't want to receive it later, return to the main program.

2-3. Action on file server

Next, the operation in the file server will be described with reference to FIG. The file server 400 has a configuration similar to that of a general file server. The file server 400 preferably stores IDs and passwords of data transmission IMAs capable of transmitting data to the file server 400.

When a file upload request comes from the data transmission IMA, the file server 400 receives the ID and password from the data transmission IMA and compares the ID and password of the data transmission IMAs stored in the file server 400 to match. Check whether there is (S710). This step may be omitted if there is no restriction on the data transmission IMA that can transmit data.

In the case of a valid ID and password, a file and file information are received from the data transmission IMA (S712). The file information includes an ID and password of a data receiving IMA capable of receiving the file, a file list storing the path names of the files to be transmitted, a time limit attribute defining a time limit for downloading the file, and the like. In case of multiple recipients, the ID and password of the data receiving IMA may be prepared separately for each recipient.

The file server 400 receiving the file and the file information from the data transmission IMA stores it (S714). It is also possible to create a folder for each data transmission IMA in case the file paths from different senders coincide, and to store the file according to the file path from the data transmission IMA under the folder. Alternatively, when the file path is generated in the data transmission IMA, its ID may be included in the file path to prevent the case where file paths from different senders coincide with each other.

When a file download request is received from the data receiving IMA, the file server 400 receives an ID and a password from the data receiving IMA and downloads the corresponding file included in the file information about the corresponding file stored in the file server 400. The ID and password of the data receiving IMA that can be received are compared with each other to check whether they match (S720).

As a result of the check, if the data receiving IMA is a legitimate data receiving IMA capable of downloading the file, the file server 400 transmits the file to the data receiving IMA (S722).

After transmitting the file, the file server 400 sets a flag indicating that the recipient has received the file in the recipient list (ID and password of data receiving IMAs capable of receiving the file) in the file information about the file. The file information of the corresponding file is updated (S724), and the file information is checked to confirm whether all the recipients have downloaded the file (S726).

If all the recipients have downloaded the file, the file is no longer stored, and thus the file and file information are deleted (S728).

On the other hand, when the file is to be deleted only when the time limit elapses according to the time limit attribute set in the file, steps S726 and S728 can be omitted.

The file server 400 also checks whether there is a file whose time limit has elapsed every predetermined time (S730), and deletes the file whose time limit has elapsed and file information of the file (S732). By doing so, the file expires regardless of whether the file has been downloaded.

2-4. Variant

Next, a modified method of data transmission linked to an e-mail system will be described.

8 is a first modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system. In the example of FIG. 8, the data transmission IMA is different from that provided on the email system 300 side rather than the transmission client 100 side.

In the example of FIG. 8, the sender transmits an e-mail according to a general e-mail transmission procedure using the transmitting client 100 (S810). The sending mail server that receives the email calls the data sending IMA. Operations in the data transmission IMA are almost the same as those described with reference to FIG. 4, and thus detailed descriptions thereof will be omitted.

As described with reference to FIG. 4, the data transmission IMA uploads a file to the file server 400 (S820), attaches a data reception IMA including file information to an email, and transmits the file to the receiving side mail server.

When the receiver requests an e-mail by accessing the receiving mail server using the receiving client 200, which is an email program installed in his computer (S830), the receiving mail server transmits the email to the receiving client 200. (S840). In this case, the e-mail includes not only a message written by the sender but also a data receiving IMA including an ID, a password for downloading the attached file, and information on the attached file.

When the recipient of the e-mail receives a file attached to the e-mail, the attached data receiving IMA is activated. Operation in the data receiving IMA is the same as described with reference to FIG. 6. As described above, the data receiving IMA requests a file from the file server 400 in which the file is stored using the information on the attached file (S850). At this time, in order to prevent a person without file access authority from downloading a file, the data receiving IMA transmits the included ID and password to the file server 400.

The file server 400 receiving the file download request checks whether the received ID and password match the ID and password assigned to the file, and transmits the file to the receiving client 200 when the file ID is matched (S860). . Operations in the file server 400 are also the same as those described with reference to FIG. 7, and thus detailed descriptions thereof will be omitted.

9 is a second modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system. In the example of FIG. 9, the data transmission IMA is provided in the sending mail server in the email system 300 instead of the sending client 100 side, and the data receiving IMA is operated in the receiving mail server.

In the example of FIG. 9, the sender transmits an e-mail according to a general e-mail transmission procedure using the transmission client 100 (S910). The sending mail server that receives the email calls the data sending IMA. Operations in the data transmission IMA are almost the same as those described with reference to FIG. 4, and thus detailed descriptions thereof will be omitted.

As described with reference to FIG. 4, the data transmission IMA uploads a file to the file server 400 (S920), attaches a data reception IMA including file information to an e-mail, and transmits the file to the receiving side mail server.

When the receiver requests an e-mail by accessing the receiving mail server using the receiving client 200, which is an email program installed in his computer (S930), the receiving mail server receives the data receiving IMA attached to the email. Call

Operation in the data receiving IMA is the same as described with reference to FIG. 6. As described above, the data receiving IMA requests a file from the file server 400 in which the corresponding file is stored using the information on the attached file (S940). At this time, in order to prevent a person without file access authority from downloading a file, the data receiving IMA transmits the included ID and password to the file server 400.

The file server 400 receiving the file download request checks whether the received ID and password match the ID and password assigned to the file, and if the file server 400 matches, transmits the file to the receiving mail server (S950). Operations in the file server 400 are also the same as those described with reference to FIG. 7, and thus detailed descriptions thereof will be omitted.

The receiving mail server which has downloaded the file from the file server 400 attaches the file to the email and transmits the file to the receiving client 200 (S960), thereby completing the file transfer from the transmitting client 100 to the receiving client 200. Will be.

10 is a third modified example of the method for transmitting large amounts of data according to the present invention using an e-mail system. 10 differs in that the data receiving IMA is operated in the receiving mail server.

When a user (sender) who wants to send data uses the sending client 100 to compose an e-mail message and attaches a file to send and selects an e-mail sending command, the data sending IMA installed on the sender's computer is automatically displayed. Driven. The data transmission IMA uploads the attached file to the file server 400 (S1010), and sends the data receiving IMA including an ID, password and information on the attached file to download the uploaded file together with the email message. Transmit to 300 (S1020).

The email including the data receiving IMA is delivered from the sending mail server to the receiving mail server in the email system 300. If the receiver requests an e-mail by accessing the receiving mail server using the receiving client 200 which is an email program installed on his computer in order to receive the mail stored in the receiving mail server (S1030), the receiving mail The server invokes the data receiving IMA attached to the email.

Operation in the data receiving IMA is the same as described with reference to FIG. 6. As described above, the data receiving IMA requests a file from the file server 400 in which the file is stored using the information on the attached file (S1040). At this time, in order to prevent a person without file access authority from downloading a file, the data receiving IMA transmits the included ID and password to the file server 400.

The file server 400 receiving the file download request checks whether the received ID and password match the ID and password assigned to the file, and if the file server 400 matches, transmits the file to the receiving mail server (S1050). Operations in the file server 400 are also the same as those described with reference to FIG. 7, and thus detailed descriptions thereof will be omitted.

The receiving mail server, which has downloaded the file from the file server 400, attaches the file to the email and transmits the file to the receiving client 200 (S1060), thereby completing the file transmission from the transmitting client 100 to the receiving client 200. Will be.

2-5. Duplicate storage

According to the present invention, when transmitting a file, the same file may be repeatedly stored in a plurality of file servers. 11 is a flowchart showing an operation in the data transmission IMA at this time, and FIG. 12 is a flowchart showing an operation in the data receiving IMA at this time.

First, the operation in the data transmission IMA is described. Operation in the data transmission IMA when the same file is repeatedly stored in a plurality of file servers is the same as in FIG. However, the difference in that the operation in S420 to upload the file to the file server is implemented as shown in FIG.

The data transmission IMA checks whether the transmission client 100 is online with the file server 400a (S1110). The list of file servers 400a, ..., 400n that can upload data is set in advance in the data transmission IMA, and the data transmission IMA attempts to upload files from the file server at the top of this list. If the file server is not online, go to step S1150 and check whether or not to upload a file to the next file server in the list (S1150).

If the file server is online, the data transmission IMA uploads the data file to the corresponding file server (S1120). If the file upload is unsuccessful, go to step S1150 to confirm whether to upload the file to the next file server in the list. If the file upload is successful, add the address of the file server to the server list (S1140). The server list is attached to the email with the data receiving IMA and delivered to the recipient.

When the file upload process is completed for one file server, the data transmission IMA asks the user whether to upload the file to another file server (S1150). If the user selects file upload to another file server, the address of the next file server is taken from the list of file servers set in the data transmission IMA, and the process is repeated from step S1110. Of course, if there is no address for the next file server in the list of file servers, it will exit.

Alternatively, instead of confirming whether the user uploads the file to another file server, it is possible to have the user upload the file to all the file servers set in the data transmission IMA. In particular, when the data transmission IMA is operated in the e-mail system 300 as shown in FIG. 8 or 9, since the user cannot receive confirmation, all files are uploaded to the set file server or the file server is set. For example, it is preferable to upload files to only three file servers.

Next, a process of downloading a file from the data receiving IMA when the file is repeatedly uploaded to a plurality of file servers will be described with reference to FIG. 12. Operation in the data receiving IMA when files are stored in multiple file servers is the same as in FIG. The difference is that the operation in S620 for downloading a file from the file server is implemented as in FIG. 12.

The data receiving IMA checks whether the receiving client 200 is online with the file server (S1210). The list of file servers 400a, ..., 400n in which the files to be received are stored is transmitted along with the data receiving IMA, and the data sending IMA attempts to download the file from the top file server in this server list. If the file server is not online, the process goes to step S1240 and a file download is attempted for the next file server in the server list.

If the receiving client 200 is online with the file server, the receiving client 200 downloads the data file from the file server (S1220). The file server may fail, so it may happen that all files cannot be downloaded. Therefore, after receiving the file download, it is checked whether all the files in the received file list are downloaded together with the data receiving IMA (S1230).

If all the files have been downloaded, the file download process is no longer needed, so the file download process is terminated. If there are more files to download, the files are downloaded from the next server in the server list. To this end, the file server that has just downloaded the file is deleted from the server list (S1240), and it is checked whether other servers remain in the server list (S1250). If there is another server in the server list, the process goes to step S1210 and the above process is repeated for the new server, and if there is no other server in the server list, the file download process is terminated. In this case, when the entire file has not been downloaded, it is preferable to restore the server list when the file download process ends in preparation for retrying the file download in FIG. 6 (S640).

3. Data transmission linked to P2P system

In addition to using e-mail, there is a method of transmitting data online by directly connecting a computer to be sent and a computer to be received. Such a system is called a peer-to-peer system.

The data transmission method of the present invention can be combined with a P2P system. The side (transmitting client) transmitting from the P2P system may transmit data through the P2P system or through the e-mail system according to the present invention when the P2P transmission is impossible. The receiving side (receiving client) receives the data according to a conventional P2P transmission method when the transmitting side transmits through the P2P system, and when the data is transmitted through the email system according to the present invention, As such, data will be downloaded using the data receiving IMA attached to the received email.

The operation of the receiving client is the same as the conventional P2P transmission method when receiving through the P2P system, and the detailed description is omitted since the operation of the receiving client is similar to that described with reference to FIG. 6.

The data transmitting side undergoes the same procedure as shown in FIG.

First, since the P2P system is based on direct communication between the receiving side and the transmitting side, it is necessary to confirm whether the transmitting side is online with the receiving side (S1310). If the transmitting client maintains the online state with the receiving client, the transmitting client combines the data to be sent with the message and transmits the data to the receiving client as in general P2P transmission (S1340). After the data is transferred, the program ends. Alternatively, if the data transfer is successful, the program may be terminated. Otherwise, the program may be repeated again from step S1310.

If the receiving side and the transmitting side are not connected to each other, the user checks whether a transmission method according to the present invention is desired (S1320). This may allow the user to confirm each time, or may set whether to use the transmission method according to the present invention for system setting of the P2P system.

If data transmission is desired according to the transmission method according to the present invention, the data transmission IMA is called (S1330). Then, as described with reference to FIG. 4, the data transmission IMA uploads a file to be transmitted to the file server and transmits a data reception IMA capable of receiving data to the receiver along with the message. Since the method of transmitting and receiving files according to the present invention is the same as described with reference to FIGS. 2 to 12, detailed description thereof will be omitted.

4. Data transfer linked to online file transfer system

It is possible to combine the file transfer method according to the present invention to an online file transfer system such as FTP (File Transfer Protocol).

The transmitting side (transmitting client) in the online file transfer system may transmit data through the online file transfer system or through an e-mail system according to the present invention when transmission through the online file transfer system is impossible. On the receiving side (receiving client), when the transmitting side transmits through the online file transfer system, the receiving side receives data according to a conventional online file transfer method, and when the data is transmitted through the email system according to the present invention. As described above, the data is downloaded using the data receiving IMA attached to the received email.

The operation of the receiving client is the same as the existing online file transfer method when receiving through the online file transfer system, and the detailed description is omitted since the operation in the receiving client is similar to that described with reference to FIG. 6. do.

While the invention has been described using some preferred embodiments, these embodiments are illustrative and not restrictive. Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the invention and the scope of the rights set forth in the appended claims.

As described above, according to the present invention, since the data is transmitted using the e-mail system, the file can be transmitted even if the receiving side is not online.

In addition, unlike file transfer through a general e-mail system, if the receiver wants to access the file server to download the file, there is an effect that the communication channel is not used unnecessarily.

In addition, since a large file is not transmitted through the email system, there is an effect that the load on the email system is reduced.

In addition, since the data receiving IMA including the ID and password for receiving data through e-mail are transmitted together, there is an effect that the transmitted file cannot be accessed by anyone other than a legitimate recipient.

In addition, since data is downloaded using the data receiving IMA including ID, password, etc., the user does not need to input ID and password one by one, thereby making it convenient to use.

Claims (16)

An email system comprising a sending email server and a receiving email server, A file server for storing transfer files, A data receiving IMA for generating information related to the transmission file and uploading the file to the file server together with the transmission file, generating a data receiving IMA including the information related to the transmission file, attaching it to an email, and transmitting the same to the email system. With the sending client, Receiving client for downloading the transmission file from the file server by calling the data receiving IMA received through the email system Data transmission system comprising a. A file server for storing transfer files, A data receiving IMA for generating information related to the transmission file and uploading the file to the file server together with the transmission file, generating a data receiving IMA including the information related to the transmission file, attaching it to an email, and transmitting the same to the email system. An email system comprising a sending email server, a receiving email server, A sending client for creating an email, attaching a transmission file, and sending it to the email system; Receiving client for downloading the transmission file from the file server by calling the data receiving IMA received through the email system Data transmission system comprising a. A file server for storing transfer files, A sending client for creating an e-mail and attaching a sending file, A receiving client for receiving email, Separating the transmission file from an email from the sending client, generating information related to the transmission file, uploading the information to the file server together with the transmission file, and generating a data receiving IMA including information related to the transmission file to the email. The sender's e-mail server including the data receiving IMA attached and transmitted, and the data receiving IMA attached to the e-mail received from the sender's e-mail server are called to download the transmission file from the file server and attach the e-mail to the e-mail. Email system consisting of the receiving email server, which is sent to the receiving client upon the client's request Data transmission system comprising a. A file server for storing transfer files, A data receiving IMA for generating information related to the transmission file and uploading the file to the file server together with the transmission file, generating a data receiving IMA including the information related to the transmission file, attaching it to an email, and transmitting the same to the email system. With the sending client, A receiving client for receiving email, Recipient E-mail server Receiving side E-mail server Receiving side which calls the data receiving IMA attached to the received e-mail, downloads the transmission file from the file server, attaches it to the e-mail and sends it to the receiving client according to the request of the receiving client. Email system consisting of an email server Data transmission system comprising a. The method according to any one of claims 1 to 4, The information related to the transmission file includes a file list including a temporary ID and password of a receiver, a file name of a data and a file location, and a time constraint attribute defining a storage period of a file. Data transmission system. 6. The data transfer system of claim 5, wherein the file server deletes the corresponding transfer file when the time limit specified by the time limit attribute elapses. 6. The data transmission system according to claim 5, wherein the data receiving IMA does not download the transmission file when the time limit specified by the time limit attribute has elapsed. The method according to any one of claims 1 to 4, The file server is a plurality, The data transmission IMA is a data transmission system, characterized in that for uploading a transmission file in duplicate in part or all of the plurality of file servers. The method of claim 8, The information related to the transmission file includes a temporary ID and password of a receiver, a server list indicating a location of file servers to store data, a file list including a data file name and a file location, and a storage expiration date of a file. And a Time Constraints attribute to define the data transfer system. The data transmission method according to any one of claims 1 to 4, wherein the transmission client and the reception client include a P2P transmission function, and when the P2P transmission is impossible, the file is transmitted through the e-mail system. system. The data transmission method according to any one of claims 1 to 4, wherein the sending client and the receiving client include an FTP transmission function, and when the FTP transmission is impossible, the file is transmitted through the email system. system. A first step of confirming whether a sender attaches a file together with an e-mail message and requests mail transmission, if the size of the attached file is larger than a predetermined size; A second step of attaching the file to an e-mail message and sending the e-mail to a recipient when the size of the attached file is not larger than a predetermined size; A third step of generating a password and a temporary ID when the size of the attached file is larger than a predetermined size; Uploading the attachment file to the file server together with the generated password and temporary ID; A fifth step of attaching a program for downloading the file, including the generated password and a temporary ID, to a message prepared by a user and sending it to an email to a recipient; Data transmission method comprising a. The method of claim 12, wherein the second step If the size of the attached file is not more than the predetermined size, step 2-1 of checking whether the user wants to transfer the file through the file server; If the user wants to transfer the file through the file server, Steps 2-2 to Step 3 above; If the user does not want to transfer the file through the file server, attaching the file to an e-mail message and sending it to the recipient by e-mail, step 2-3 Data transmission method comprising a. The method of claim 12, The fourth step includes uploading files to a plurality of file servers and creating a list of uploaded file servers. And in the fifth step, the program for downloading the file includes a list of the file server. The method according to any one of claims 12 to 14, Prior to the first step, the sender attempts to connect to the receiver using a P2P client and transmits the file using the P2P client if the receiver is online, and goes to the first stage if the receiver is not online. A data transmission method characterized by the above-mentioned. The method according to any one of claims 12 to 14, Before the first step, if the sender attempts to upload the file using an FTP client and the file upload fails or the sender wants to be notified via e-mail, the method includes the step of moving to the first step. Way.