KR20160042839A - Data communication apparatus using cloud service and method for data processing thereof - Google Patents

Abstract

The present invention relates to a data communication apparatus using cloud service and a data processing method thereof. The data processing method comprises: a step of coding original data in a distributed manner to generate a plurality of pieces; and a step of transmitting at least some of the pieces among the generated pieces to a plurality of cloud servers in a distributed manner. The cloud servers include at least two cloud servers, separately operated by different cloud service providers from one another. The purpose of the present invention is to provide a data communication apparatus to save data in a cloud server with improved security.

Description

TECHNICAL FIELD [0001] The present invention relates to a data communication apparatus using a cloud service, and a data processing method thereof. [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data communication apparatus and a data processing method thereof, and more particularly, to a data communication apparatus for exchanging data with a cloud server and a data processing method thereof.

Cloud services are a mix of computing and communication services, such as virtualization, utility, and on demand computing. Typically, virtualized computer systems are used to provide users with a variety of software, security solutions, or computing resources. Means the service provided.

In particular, the cloud service can provide a wide range of data storage services to the user, allowing the user to store programs or documents individually stored in the personal computer device in an Internet-based cloud server. And, the user can drive or browse a program or a document stored in the cloud server through various terminals such as a personal computer or a smart phone. This cloud service has the advantage of allowing the user to freely access the stored data without being affected by the place, and to utilize a richer computing resource than the user can personally provide.

On the other hand, as the data storage service using the cloud is widely used, secret data such as personal information, private data, and business secrets of the enterprise are increasingly stored in the cloud server. Therefore, in order to use the cloud service safely, a security measure for protecting the data stored in the cloud server from a third party is required.

In addition, when the cloud service is used, the cloud server can not use the data stored in the cloud server if the cloud server is disabled due to communication failure, malfunction, or other reasons for failure, and the possibility that the stored data may be lost have. Therefore, in order to utilize the cloud service stably, a means for successfully restoring the stored original data despite the failure of such a cloud server is required.

An object of the present invention is to provide a data communication apparatus and a data processing method thereof for storing data in a cloud server or reading data from a cloud server in a security-enhanced manner.

Another object of the present invention is to provide a data communication apparatus and a data processing method for the same that can restore original source data successfully even if a cloud server storing data is disabled.

It is another object of the present invention to provide a data communication apparatus and a data processing method of the same that have improved data transmission speed and space efficiency of a cloud service.

According to embodiments of the present invention, a data processing method of a data communication apparatus includes the steps of: generating a plurality of pieces by dispersively coding original data; Distributing at least some pieces of the generated plurality of pieces to a plurality of cloud servers, wherein the plurality of cloud servers each include at least two cloud servers operated by different cloud service providers .

In an embodiment, the plurality of pieces comprise one or more pieces of data and one or more pieces of parity.

In an embodiment, the original data is recoverable from the at least a portion of the plurality of pieces, and the number of the at least some pieces is equal to or greater than the number of the one or more data pieces.

In an embodiment, the at least some fragments comprise at least one of the one or more parity fragments.

In an embodiment, the at least some fragments do not include the one or more data fragments.

As an embodiment, generating a plurality of fragments may include encrypting the source data; And generating the plurality of fragments by variably coding the encrypted original data.

In an embodiment, the keys used for encryption of the original data are distributed coded and distributed to the plurality of cloud servers.

In an embodiment, the number of the generated plurality of pieces or the size of each of the generated plurality of pieces is determined by referring to the number of the plurality of cloud servers or the storable space of the plurality of the cloud servers.

In an embodiment, the step of distributedly transmitting to the plurality of cloud servers comprises transmitting the at least some fragments to at least a part of the plurality of cloud servers sequentially or in parallel according to a predetermined level of the raid .

According to embodiments of the present invention, a data processing method of a data communication apparatus includes: reading a plurality of pieces from a plurality of cloud servers; And decoding the read pieces to restore original data, wherein the plurality of cloud servers each include at least two cloud servers operated by different cloud service providers.

In one embodiment of the present invention, the step of restoring the original data comprises: decrypting the read pieces to restore encrypted data; And decoding the encrypted data to restore the original data.

As an embodiment, the decoding of the read plurality of fragments is performed through a decoding algorithm of the distributed coding method used to generate the plurality of fragments.

As an embodiment, the decryption of the encrypted data is performed through a decryption algorithm of the encryption method used to encrypt the original data.

According to embodiments of the present invention, a cloud server that provides a cloud storage service receives and stores a part of a plurality of pieces generated by distributing and encoding original data from a data communication device, and stores the stored pieces into an external device Wherein the plurality of pieces further comprise a different piece of the piece that is different from the piece, and the other piece of piece comprises another cloud storage service different from the cloud storage service And is provided to the external device in response to a request from the external device.

In some embodiments, the fractional fragments or the fractional fragments comprise parity fragments generated by the distributed coding.

According to embodiments of the present invention, data can be stored in the cloud server or read from the cloud server in a security-enhanced manner through data encryption, distributed coding, or distributed storage for a plurality of cloud servers.

In addition, since the data is distributed and stored in a plurality of cloud servers, even if some cloud servers are disabled, the original data can be successfully restored from the remaining cloud servers.

In addition, since the entire data is stored in parallel in a plurality of cloud servers, the data upload speed and download speed are improved, and the storage space of the cloud server can be efficiently utilized.

1 is a block diagram illustrating a data processing method using a cloud service according to an embodiment of the present invention.
Figure 2 is a schematic diagram that schematically illustrates distributed coding, in accordance with one embodiment of the present invention.
3 is a block diagram illustrating a data processing method using a cloud service according to another embodiment of the present invention.
4 is a block diagram illustrating a data processing method using a cloud service according to another embodiment of the present invention.
5 is a block diagram illustrating a method of uploading data to a plurality of cloud servers and a method of downloading data from a plurality of cloud servers, according to embodiments of the present invention.
6 is a block diagram illustrating a method of distributing and transmitting data to cloud servers according to a storable space of cloud servers.
7 is a block diagram illustrating a method for transmitting data at different raid levels according to the storable space of storable cloud servers.
8 is a flowchart illustrating a data processing method using a cloud service according to embodiments of the present invention.
FIG. 9 is a flow chart embodying step S110 of FIG. 8 according to an embodiment of the present invention.
FIG. 10 is a flowchart illustrating the step S140 of FIG. 8 according to an embodiment of the present invention.

The following detailed description of the invention refers to the accompanying drawings, which illustrate, by way of illustration, specific embodiments in which the invention may be practiced. It should be understood that the various embodiments of the present invention are different, but need not be mutually exclusive. For example, certain features, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the invention in connection with one embodiment.

It should also be understood that the position or arrangement of the individual components within each disclosed embodiment can be variously modified without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is principally defined by the appended claims, encompassed by the appended claims and their equivalents. Where similar reference numerals are used in the figures, like reference numerals refer to the same or similar functions for various embodiments.

Hereinafter, the contents and ideas of the present invention will be described with reference to the accompanying drawings.

1 is a block diagram illustrating a data processing method using a cloud service according to an embodiment of the present invention. Referring to FIG. 1, a cloud data storage system includes a data communication device 110, a network 120, and a plurality of cloud servers 131, 132, and 133.

1, the data communication apparatus 110 distributes the original data 111 to generate a plurality of pieces 112, and then transmits the pieces of data 112 to the plurality of cloud servers 131, 132, and 133 via the network 120. [ . At this time, the data communication device 110 may provide all of the plurality of decoded pieces 112 to the cloud servers 131, 132, 133 as the storage data 122, May be provided to the cloud servers 131, 132, and 133 as the storage data 122.

The data communication apparatus 110 is connected to the network 120 and transmits data to the cloud servers 131, 132 and 133 or receives data from the cloud servers 131, 132 and 133. The data communication device 110 may be a personal computer, a public computer, a server or a home application (e.g., a smart TV, a refrigerator, a home security device, etc.) A multi-function device, an office security device, etc.). Alternatively, data communication device 110 may comprise a mobile terminal, a cellular phone, a smart phone, a laptop computer, a notebook computer, or a mobile device (e.g., GPS terminal, smart watch, etc.) with wireless communication means.

The data communication apparatus 110 generates a plurality of pieces 112 by distributing the original data 111 in a distributed manner to distribute the original data 111 to the cloud servers 131, Here, the distributed coding is a coding method for generating a plurality of fragments from original data. If the original data is divided to generate n pieces, then only the k pieces of the n pieces are acquired, (Where n? K? 1). At this time, it is possible to arbitrarily decide how many pieces (n) of original data are to be divided and how many pieces (k) of pieces of original data can be restored. For example, when the data communication apparatus 110 performs [n, k] distributed coding on the original data 111, k data pieces containing the data contents of the original data 111 and nk All n pieces of parity pieces are generated. And acquiring any of the different k pieces of the generated n pieces, the data communication device 110 can successfully recover the original data 111. [

The distributed coding used in the present invention may be, for example, erasure coding. A typical example of erasure coding is reed-solomon coding, and detailed contents of erasure coding and Reed-Solomon coding are well known in the art, and a description thereof will be omitted here.

The data communication apparatus 110 distributes and stores at least a part 122 of the plurality of generated pieces 112 to the plurality of cloud servers 131, 132 and 133. As an embodiment, at least some of the pieces 122 that are distributed stored include a minimum number (e.g., k) of pieces that can be recovered from the original data 111. [ At this time, at least some of the pieces 122 may be stored in different cloud servers, respectively, or two or more of them may be stored in the same cloud server. Meanwhile, although three cloud servers 131, 132, and 133 are shown here, this is an example, and the present invention is not limited thereto. For example, the data communication device 110 may distribute at least some of the pieces 122 of the plurality of pieces 112 to four or more cloud servers.

The network 120 is a communication network for relaying the data communication apparatus 110 and the cloud servers 131, 132, and 133. The network 120 may be any of various types of networks, including wired networks or wireless networks, for example mobile communication networks such as WiBro, UMTS (3G), E-UMTS (4G) or Femtocell, wireless networks such as WiFi or Bluetooth, But is not limited to, a wired network such as a LAN, a telephone network, or a wired cable.

A plurality of cloud servers 131, 132, and 133 are computing devices that provide cloud storage services to a client (e.g., data communication device 110), which are operated by different cloud storage service providers, And is configured to operate independently. For example, a plurality of cloud servers 131, 132, and 133 may each require a separate user authentication procedure (e.g., login) for the same data communication device 110. Each of the cloud servers 131, 132 and 133 is communicatively coupled to the data communication device 110 via the network 120 and communicates with the data communication device < RTI ID = 0.0 > 110 to provide a common or customized data storage service. Each of the cloud servers 131, 132, and 133 may have log-on means for individually or integrally controlling the connection of the data communication device 110. [

In the present invention, each of the cloud servers 131, 132, and 133 is typically illustrated as being operated by different cloud storage service providers (e.g., Dropbox, SkyDrive, Google Drive, etc.) But is not limited thereto. For example, any two of the cloud servers 131, 132, and 133 may be servers operated by the same cloud provider. The specific configuration of each of the cloud servers 131, 132, and 133 and the general service providing method are well known in the art, and a description thereof will be omitted here.

According to the above configuration, since the distributed coded pieces of original data are distributed and stored in a plurality of cloud servers, even if a part of the cloud servers (less than the minimum recoverable number k) is hacked, . Therefore, the security of the cloud storage service is improved.

In addition, even if some of the pieces stored in the cloud servers (only the minimum number (k) that can be restored) are acquired, the original data can be restored. Therefore, even if some cloud servers are disabled, Can be restored successfully. Therefore, the reliability and stability of the cloud storage service are improved.

In addition, since the original data is divided and stored in parallel in a plurality of cloud servers, data uploading speed and downloading speed can be improved, and cloud servers providing small storage capacity can be collected to store a large amount of data. The storage space can be efficiently utilized. Thus, the efficiency of the cloud storage service is improved.

Figure 2 is a schematic diagram that schematically illustrates distributed coding, in accordance with one embodiment of the present invention. Referring to FIG. 2, a [5, 2] distributed coding method 10 is shown.

As described briefly above, the [n, k] distributed coding method is a distributed coding method for generating k pieces of data pieces and n-k pieces of parity pieces by dividing original data. In this distributed coding method, when k data pieces among the generated pieces are acquired and decoded, not only original data but also all n pieces (k pieces of data pieces + nk Parity fragments) (even if all k pieces are parity fragments), the original data can be successfully restored. As an example of such distributed coding, deletion coding has been described above.

2, when the original data 11 is encoded by the [5, 2] distributed coding method, two data pieces 12 and 13 and three parity pieces are generated. The contents of the original data 11 are not exposed to the parity pieces 14, 15 and 16 although the contents of the original data 11 are exposed in the data pieces 12 and 13 as they are.

Then, in the original data restoring process, the user (or the data communication apparatus) obtains only at least two pieces of the generated five pieces 12, 13, 14, 15, 16 and decodes the decoding algorithm of the same distributed coding method Can be decoded to restore the original data. At this time, the pieces to be acquired by the user do not need to be the data pieces 12 and 13, and any one of the data pieces 12 and 13 and the parity pieces 14, 15, Or both of the two pieces may be obtained from the parity pieces 14, 15, 16.

Here, it is assumed that the user has acquired two pieces 14, 15 of the parity pieces 14, 15, 16. The user decodes the acquired parity fragments 14 and 15 through a decryption algorithm of the same distributed coding method as that in encoding. When the decoding is completed, the original data 17 is restored as a result.

On the other hand, since details of the distributed coding method and its decoding algorithm for generating n pieces of data from original data and recovering original data by acquiring k pieces of arbitrary pieces of the data pieces are well known in the art, .

3 is a block diagram illustrating a data processing method using a cloud service according to another embodiment of the present invention. Referring to FIG. 3, a cloud data storage system includes a data communication device 210, a network 220, and a plurality of cloud servers 231, 232, and 233.

3, the configuration and method of operation of the data communication device 210, the network 220, and the plurality of cloud servers 231, 232, 233 are similar to those of the data communication device 110, network 120, Are substantially the same as the cloud servers 131, 132, and 133 of FIG. 3, the data communication apparatus 210 generates parity pieces (i.e., nk > k) of the number of data pieces (e.g., k) generated when the original data 211 is distributed- It is exemplified that only the parity pieces are distributedly stored in the plurality of cloud servers 231, 232, and 233. Since the contents of the original data are not exposed directly to the parity fragments, in this case, the contents of the original data can be safely protected even if the distributed parity fragments are hacked.

More specifically, the data communication apparatus 210 first distributes the original data 211 by, for example, [6, 3] to three data pieces 212 and three parity pieces 213 And generates a plurality of pieces constituted. In order to enhance the security of the original data, only three pieces of parity pieces 213 are distributedly stored in the plurality of cloud servers 231, 232, and 233 through the network 120. [6, 3] In the distributed coding method, if the user acquires three or more pieces of all six pieces 212 and 213, the user can obtain the original data regardless of whether the acquired pieces are a data piece or a parity piece Can be restored. Therefore, according to the embodiment of FIG. 3, there is no problem for the user to download the parity pieces 222 stored in the cloud servers 231, 232, and 233 to restore the original data, There is an advantage that it is safer to hack because it uses only the parasitic pieces which are not exposed.

Meanwhile, the previously generated data pieces 212 are left unused or discarded (221).

4 is a block diagram illustrating a data processing method using a cloud service according to another embodiment of the present invention. 4, a cloud data storage system includes a data communication device 310, a network 320, and a plurality of cloud servers 331, 332, and 333.

4, the configuration and operation of the data communication device 310, the network 320, and the plurality of cloud servers 331, 332, 333 are similar to those of the data communication device 110, the network 120, Are similar to the cloud servers 131, 132, and 133 of FIG. 4, the data communication apparatus 310 first encodes the original data 311 and decodes the encrypted data 312 to generate a plurality of pieces (i.e., a plurality of pieces) to be stored in the cloud servers 131, 132, and 133 313). Since the pieces 322 distributedly stored in the cloud servers 131, 132, and 133 are encrypted pieces, in this case, there is an advantage of being safer for hacking from the outside.

In this embodiment, the data communication apparatus 310 encrypts and encrypts the original data 311 first. At this time, the encryption may be symmetric key encryption or asymmetric key encryption. Symmetric key encryption is a method of fast encryption and decryption using a relatively short key. On the other hand, asymmetric key encryption is a method of using a public key disclosed in encryption and a private key corresponding to a public key in decryption. An example of symmetric key encryption is AES (Advanced Encryption Standard) encryption, and an example of asymmetric key encryption is Rivest Shamir Adleman (RSA) encryption. In the present embodiment, it is assumed that AES encryption is used during symmetric key encryption for encryption of the original data 311. [ However, the scope of the present invention is not limited thereto, and various data encryption algorithms in addition to AES encryption can be used for encrypting the original data 311

The data communication device 310 then distributes the encrypted data 312 to generate a plurality of fragments 313 and transmits at least a portion 322 of the generated fragments 313 through the network 320 To the plurality of cloud servers 331, 332, and 333 (321). The method by which the data communication apparatus 310 distributes generated fragments 313 to the cloud servers 331, 332 and 333 is substantially the same as that described in FIG.

As an embodiment, the data communication device 310 randomly generates and uses a new key each time it encrypts new data in order to securely protect the key used for encryption. The used keys may be stored in the data communication device 310 or the used keys may be stored in the cloud servers 331, 332, and 333. When the used key is stored in the cloud servers 331, 332, and 333, the data communication device 310 generates a plurality of key fragments by distributing the key to secure stability and reliability of the stored key , The key fragments may be distributedly stored in the cloud servers 331, 332, and 333. In this case, even if some key fragments are lost, the original key can be restored from the remaining key fragments. On the other hand, the method of distributive coding the key may differ from the method used to decode the encrypted data 312. For example, a shamir secret sharing scheme can be used to decode the key.

When restoring the original data 311 from the distributed pieces 322, the data communication device 310 searches the cloud servers 331, 332, and 333 for the minimum number required for recovery (e.g., (K) or more pieces described in < / RTI > Then, the decrypted pieces are decrypted to recover the encrypted data 312. Then, the data communication apparatus 310 restores the original data 311 from the encrypted data 312 by using the key previously used for encryption. If the keys are distributed and stored in the cloud servers 331, 332 and 333 in the form of key pieces, the data communication device 310 transmits the key pieces to the cloud servers ( 331, 332, and 333, and decrypts the downloaded key fragments to restore the original key in advance.

According to the above configuration, since data is encrypted prior to data distribution, it can be more secure against hacking from the outside.

5 is a block diagram illustrating a method of uploading data to a plurality of cloud servers and a method of downloading data from a plurality of cloud servers, according to embodiments of the present invention. The uploading method and downloading method of Fig. 5 can be applied in common to the embodiments described in Figs. 1-4.

(a) Upon uploading, the data communication device 410 encodes the original data 411 through [n, k] distributed coding to generate a plurality of fragments. However, the data communication apparatus 410 may encrypt the original data 411 before [n, k] distributed coding. In this case, [n, k] distributed coding is performed on the encrypted data.

The data communication device 410 distributes the generated pieces to the plurality of cloud servers 430 through the network 420. [ At this time, the data communication apparatus 410 may distribute all of the pieces 421 generated as shown in FIG. 5, or may distribute only a part of the generated pieces. However, when only a part of the data is dispersively stored, the number of pieces of data to be scattered and stored must be equal to or larger than the minimum number (in this case, k) required for restoration of the original data.

(b) Upon downloading, the data communication device 410 downloads the pieces 422 distributedly stored in the plurality of cloud servers 430 via the network 420. At this time, the data communication device 410 does not need to download all the pieces of data scattered and stored in the plurality of cloud servers 430, but only needs to download data of a minimum number (k) necessary for restoration of original data.

For example, assume that a portion 431 of a plurality of cloud servers 430 is disabled due to failure. In this case, if the number of pieces stored in the remaining cloud servers 432 and 433 is equal to or greater than the minimum number (k) required for restoration, the data communication apparatus 410 stores the restored data in the remaining cloud servers 432 and 433 The original data 412 can be restored by decoding only the fragments through a decoding algorithm of the distributed coding method.

At this time, if the downloaded pieces 422 are those in which the encrypted data is distributed-coded, the data communication device 410 first restores the encrypted data from the downloaded pieces 422, And restores the original data 412.

6 is a block diagram illustrating a method of distributing and transmitting data to cloud servers according to a storable space of cloud servers. In FIG. 6, the data communication apparatus 510 monitors or confirms the storable space of the cloud servers 531, 532, and 533, and adjusts the distributed coding method accordingly.

6, the available space of the data communication apparatus 510 for the first cloud server 531, the second cloud server 532 and the third cloud server 533 is 15 gigabytes, 2 gigabytes, and 7 gigabytes, respectively, Assume Gigabyte. At this time, the second cloud server 532 can not store pieces exceeding 2 gigabytes because the space that can be stored is 2 gigabytes.

Accordingly, the data communication device 510 confirms the usable space of the cloud servers 531, 532, and 533, and determines that the size of the pieces 512 and 513 generated according to the confirmation result is less than 2 gigabytes Adjust the coding method. For example, when the size of the generated pieces 512 and 513 is 2 gigabytes, two pieces of data are generated from the original data 511. Therefore, in this case, the [n, 2] distributed coding method is used. On the other hand, when the size of the generated pieces 512 and 513 is 1 gigabyte, four pieces of data are generated from the original data 511. Fig. Therefore, in this case, the [n, 4] distributed coding method is used. Since n is the number of data pieces plus the number of parity pieces, it can be determined freely according to the number of parity pieces desired by the user.

In the embodiment of FIG. 6, the [3 + 2, 2] distributed coding method in which the generated pieces 512 and 513 are 2 gigabytes and the number of parity fragments is 3 has been illustrated. In this example, the data communication device 510 sends three pieces (B, C, D) of the generated pieces 512, 513 to the first cloud server 531, the second cloud server 532, And separately stored in the cloud server 533, and the remaining pieces A and E are not used. 1 to 5 that data communication device 510 can recover original data 511 only by obtaining only two pieces from cloud servers 531, 532, and 533. In this case, The same as described above.

7 is a block diagram illustrating a method for transmitting data at different raid levels according to the storable space of storable cloud servers. In FIG. 7, the data communication apparatus monitors or confirms the storable space of the cloud servers 631, 632, 633 similarly to FIG. 6, and distributes and distributes the original data accordingly. However, in FIG. 7, when the pieces are stored in the plurality of cloud servers 631, 632, and 633, predetermined levels of the raid are applied to store the pieces sequentially or in parallel.

7, the storable space and the configuration state of the first cloud server 631, the second cloud server 632 and the third cloud server 633 are the same as those of the first cloud server 531, The third cloud server 532 and the third cloud server 533, respectively.

In this embodiment, a data communication device (not shown) can store pieces by applying a specific raid level, depending on the number of available cloud servers 631, 632, 633 and their storage space. For example, a data communication device may distributively code five source data to generate five sets of pieces 641, 642, 643, 644, and 645, each individual piece having a size of one gigabyte . Also, the first piece set 641 and the second piece set 642 are each composed of a total of three pieces each including one data piece and two parity pieces, and the third piece set 643 is composed of two pieces A fourth piece set 644 and a fifth piece set 645 are composed of a total of six pieces including a data piece and four parity pieces, .

Under these assumptions, the data communication device distributes and stores the data sequentially from the first piece set 641 to the fifth piece set 645 to the cloud servers 631, 632, and 633. Since the second cloud server 632 has 2 gigabytes of space available for storing, it is possible to apply the raid 5 to the first piece set 641 and the second piece set 642 so that the three cloud servers 631, 632, 633 ) In a manner such that they are alternately stored. Since there are two cloud servers available when storing the third piece set 643, the data communication device stores the third piece set 643 by applying the raid 5 to the two cloud servers 631 and 633, Are stored one by one. When storing the fourth piece set 644, since the piece to be stored is one piece of data and one piece of parity, it is possible to apply the RAID 1 to the first cloud server 631 in the form of a mirror, And stores them in the third cloud server 633, respectively. Alternatively, a plurality of pieces may be stored in one cloud server by applying Raid 0. For example, the data communication device may store all of the fifth piece set 645 in the first cloud server 631. [

The data communication apparatus can select which level of the RAID level to apply to the plurality of cloud servers, depending on the number of available cloud servers and their storage space.

8 is a flowchart illustrating a data processing method using a cloud service according to embodiments of the present invention. Referring to FIG. 8, the data processing method includes steps S110 to S140.

In step S110, the data communication device (for example, 110 in FIG. 1) distributes the original data (for example, 111 in FIG. 1) to generate a plurality of pieces. The distributed coding method at this time may be, for example, a Reed-Solomon coding method among deletion coding methods. The generated pieces may include at least one data piece and at least one parity piece.

In step S120, the data communication device transmits the pieces of at least some of the generated pieces to a plurality of cloud servers (e.g., 131, 132, and 133 in FIG. 1) through a network (e.g., . At this time, the number of at least some fragments to be dispersively stored is equal to or greater than the minimum number of fragments required to restore the original data.

The steps S110 and S120 are data storing steps. When the step S120 is completed, the original data is distributed and stored in a plurality of cloud servers. Subsequent steps S130 and S140 are a data reading step or a data restoring step, which is performed when the data communication apparatus restores the original data from the scattered pieces.

In step S130, the data communication apparatus reads out distributedly stored pieces from at least a part of the plurality of cloud servers. The number of pieces to read is equal to or greater than the minimum number of pieces needed to restore the original data.

In step S140, the data communication apparatus decodes the read fragments through a decoding algorithm of the same distributed coding method used in step S110, and restores the original data. Meanwhile, other details of the configuration and operation method of the data communication apparatus not described here are the same as those described in Figs. 1 to 7.

According to the above configuration, since the distributed coded pieces of original data are distributed and stored in a plurality of cloud servers, even if a part of the cloud servers (less than the minimum recoverable number k) is hacked, . Therefore, the security of the cloud storage service is improved.

In addition, even if some of the pieces stored in the cloud servers (only the minimum number (k) that can be restored) are acquired, the original data can be restored. Therefore, even if some cloud servers are disabled, Can be restored successfully. Therefore, the reliability and stability of the cloud storage service are improved.

In addition, since the original data is divided and stored in parallel in a plurality of cloud servers, data uploading speed and downloading speed can be improved, and cloud servers providing small storage capacity can be collected to store a large amount of data. The storage space can be efficiently utilized. Thus, the efficiency of the cloud storage service is improved.

FIG. 9 is a flow chart embodying step S110 of FIG. 8 according to an embodiment of the present invention. Referring to FIG. 9, step S110 includes steps S111 and S112.

In step S111, the data communication apparatus encrypts the original data. At this time, the details of the method of encrypting the original data are the same as those described in Fig.

In step S112, the data communication apparatus variably codes the encrypted data to generate a plurality of pieces. The distributed coding method at this time may be, for example, a Reed-Solomon coding method among deletion coding methods. The generated fragments may include at least one encrypted data fragment and at least one parity fragment.

When the step S112 ends, the process proceeds to the step S120 of FIG.

According to the above-described configurations, since the original data is encrypted and distributed to the cloud servers, the security of the stored data is improved.

FIG. 10 is a flowchart illustrating the step S140 of FIG. 8 according to an embodiment of the present invention. Referring to FIG. 10, step S140 includes steps S141 and S142.

When step S130 of FIG. 8 is finished, step S141 is started.

In step S141, the data communication apparatus 110 decrypts the read fragments to recover the encrypted data. At this time, fragments read using the same distributed coding method used in step S112 of FIG. 9 can be decoded.

In step S142, the data communication apparatus 110 decrypts the encrypted data and restores the original data. At this time, the details of the method of restoring the original data from the encrypted data are the same as those described in Fig.

According to the above arrangement, the original original data is restored from the encrypted and distributed pieces.

On the other hand, the expression that the data communication device stores fragments in the cloud server means that the data communication device transmits the fragments to the cloud server so that the fragments are stored in the cloud server.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Also, although specific terms are used herein, they are used for the purpose of describing the invention only and are not used to limit the scope of the present disclosure as defined in the claims or the claims. Therefore, the scope of the present specification should not be limited to the above-described embodiments, but should be defined by the appended claims and their equivalents.

110, 210, 310, 410, 510: Data communication device
631, 633, 633, 633, 631, 432, 433, 531, 532, 533, 631, 332, 333, 331, 332, 333,
120, 220, 320, 420: network
111, 211, 311, 411, 511: original data

Claims (8)

The data communication device distributively coding the original data to generate a plurality of pieces comprising one or more pieces of data and one or more pieces of parity;
The data communication device distributing at least some pieces of the plurality of pieces generated by the data communication device to a plurality of cloud servers,
The plurality of cloud servers each including at least two cloud servers operated by different cloud service providers,
Wherein generating the plurality of pieces comprises:
Encrypting the original data; And
And generating the plurality of fragments by distributing the encrypted original data, wherein the key used for the encryption of the original data is distributed-coded by the data communication device to be distributed to the plurality of the cloud servers Stored,
Wherein the data communication device is a user terminal directly connected to the plurality of cloud servers via a network for communicating data without going through a proxy server.
The method according to claim 1,
Wherein the distributed transmission comprises:
Wherein the number of parity fragments distributed and transmitted to the plurality of cloud servers is determined by dividing the number of parity fragments transmitted to the plurality of cloud servers by the number of parity fragments distributed to the plurality of cloud servers, Of the data communication apparatus.
The method according to claim 1,
Wherein the number of generated pieces or the size of each of the generated plurality of pieces is determined by referring to the number of the plurality of cloud servers or the storable space of the plurality of cloud servers .
The method according to claim 1,
The method of claim 1,
And sending said at least some pieces to said at least some of said plurality of cloud servers sequentially or in parallel according to a predetermined level of raid.
The data communication device reading a plurality of pieces from a plurality of cloud servers; And
And decoding the plurality of fragments read by the data communication apparatus to recover original data,
The plurality of cloud servers each including at least two cloud servers operated by different cloud service providers,
Wherein the step of restoring the original data comprises:
Restoring a key used for encryption distributed to the plurality of cloud servers;
Decrypting the read pieces using the key used for the restored encryption and restoring the encrypted data; And
And decrypting the encrypted data to restore the original data,
Wherein the data communication device is a user terminal directly connected to the plurality of cloud servers via a network for communicating data without going through a proxy server.
6. The method of claim 5,
Wherein the decoding of the read plurality of fragments is performed through a decoding algorithm of a distributed coding method used to generate the plurality of fragments.
The method according to claim 6,
Wherein the decryption of the encrypted data is performed through a decryption algorithm of an encryption method used to encrypt the original data.
6. The method of claim 5,
Wherein the plurality of fragments read from the data communication device comprises at least a portion of parity fragments generated from original data and distributed to the plurality of cloud servers, Wherein the number of data fragments generated from the source data is equal to or greater than the number of data fragments generated from the source data.

Images