Abstract:
A data protection device capable of securing data in a data storage device is disclosed, comprising a disk space allotment unit, a marking unit, and an archiving unit. The disk space allotment unit undertakes to reorganize multiple sectors in the data storage device for allotment of disk space to newly defined sections to be used in the present scheme, such as a working data section, a sector index table and a duplicate data section. The marking unit is to check and update the data flags in the sector index table when data are written into respective sectors of the working data section, where the data flag indicates whether the write status of certain sector is enabled. The archiving unit is to reverse the above process so as to restore the original data in the working data section and data flag in the sector index table.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a data protection device and a method of securing data, and in particular to a device installation that supports all types of storage media interface with higher data access rate and more efficient usage of disk space. 
   2. The Related Art 
   Conventional data protection is based on the hardware implementation of a data protection circuit, which is installed between a conventional hard disk interface and the data bus. For the operating system, the specially adapted hard disk is treated as a conventional hard disk, with no need of any driver programs. Data can be written directly into a data storage device without any driver programs. Therefore, the data access rate of the hard disk is not affected, only that the disk operation has become more secure. 
   However, there is a limitation to using the prior art data protection technique, which can only be used on the storage media interface that is invariably set for two IDE hard disks or logical drives. After assigning the disk space for the primary data area and the virtual data area, the disk space remaining is allotted to logical drives, which is the disk space that a user can utilize. But this prior art data protection technique cannot be used on newer generation of storage media interface cards that are often used on a single hard disk, such as SATA. Therefore, the operation mode and architecture of the prior art technique need to be adjusted to meet the requirements of current hard disk technology. 
   Another inherent weakness in the architecture and the operation mode of the prior art technique is that the allotment of disk space to the primary data area and the virtual data area has to be equal. Since the data address of the saved in a hard disk might not be contiguous, the one-to-one copying of the entire data block though easy to implement often is a waste of the disk space. Therefore, the overall data access rate is slowed down because of the unnecessary disk action on the non-data sectors. 
   Since the prior art technique adopts the one-to-one copying, the system can only perform inflexible data copying and data recovery, but such system cannot support multiple node data protection and multiple selection of data reference point for archiving and data restoration. 
   SUMMARY OF THE INVENTION 
   The primary objective of the present invention is to provide a data protection device that supports all types of storage media interface. 
   The secondary objective of the invention is to provide a data securing technique that makes use of data flags recorded in a sector index table to indicate the write status of certain sectors when data are written into certain sectors, whereby the disk space needed for archiving can be considerably reduced, and the overall data access rate can be shortened. 
   The third objective of the invention is to provide a data securing technique that enables users to define the data reference point for archiving and data restoration operations, such as certain hour or date, and supports multiple node data protection through overlapping data copying and restoration processes. 
   In accordance with the first aspect of the invention, the data protection device is composed of a disk space allotment unit, a marking unit and an archiving unit. 
   In accordance with the second aspect of the invention, the disk space allotment unit is to reorganize multiple sectors existing in the data storage device for allotment of disk space to newly defined sections, such as a working data section, a sector index table and a duplicate data section of the data protection device. 
   In accordance with the third aspect of the invention, the marking unit is to mark the data flag of a certain sector in the sector index table at the same time that data are written into the working data section, where the data flag is used to indicate whether the write status of certain sector is enabled. 
   In accordance with the fourth aspect of the invention, the archiving unit is to use the data flag of a certain sector marked in the sector index table to copy the data of respective sector from the working data section and associated data flag value from the sector index table to the duplicate data section. 
   In accordance with the fifth aspect of the invention, a data recovery unit is included in the data protection device, so that when some of the data saved in the data protection device are corrupted or the data storage device is attacked by computer viruses, the user is able to invoke the data recovery procedure to restore the original data in the working data section using the data copy from the duplicate data section. 
   In accordance with the sixth aspect of the invention, a disk space tracking unit is to collect updated information of disk space used so far and disk space still remaining in the working data section, the sector index table, and the duplicate data section. 
   In accordance with the seventh aspect of the invention, every time when the archiving unit or the data recovery unit is invoked, the disk space tracking unit is first consulted to obtain updated information about the disk usage in order to prevent overwriting of any valid data in the destination data section. Also, through the service of the disk space tracking unit, the user is able to obtain useful information about the disk usage in the working data section, the sector index table and the duplicate data section continuously for other applications. 
   The present invention will become more obvious from the following description when taken in connection with the accompanying drawings, which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a block diagram of the first embodiment of the present invention; 
       FIG. 2  is a disk space allotment diagram in accordance with the present invention; 
       FIG. 3  is a diagram showing the data pattern in the working data section and respective data flags marked in the sector index table; 
       FIG. 4  is a diagram showing the data pattern in the duplicate data section being derived from the data patterns shown in  FIG. 3 ; 
       FIG. 5  is a block diagram of the second embodiment of the invention; 
       FIG. 6  is a block diagram of the third embodiment of the invention; 
       FIG. 7  is a block diagram of the fourth embodiment of the invention; and 
       FIG. 8  is a block diagram of the fifth embodiment of the invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring to  FIG. 1 , a data protection device  10  in the first preferred embodiment of the present invention is composed of a disk space allotment unit  18 , a marking unit  20  and an archiving unit  22 . Further, the data protection device  10  is connected by a host interface  12  to a data communication line (not shown), so that the operating system is able to access data saved in a data storage device  16  connected through a peripheral interface  14 . 
   The data securing technique employed by the data protection device  10  in accordance with the present invention bears some resemblance to the prior art technique, such as the use of the conventional data copying and restoration procedures for manipulation of data in the data storage device, but the present invention has introduced the re-allocation of the entire disk space on the storage device so as to achieve higher data access rate and more efficient usage of disk space, in which multiple sectors existing in the data storage unit  16  are first reorganized for allotment of disk space to newly defined sections, such as a working data section, a sector index table and a duplicate data section. 
   Referring to  FIG. 2 , the disk space allotment for the working data section  30 , sector index table  31  and duplicate data section  34  in accordance with the present invention is shown. The disk space allotment unit  18  is to implement the allotment instruction given by the user through an input device. The entire disk space of the data storage device  16  is reconstructed, that is multiple sectors on a hard disk are reorganized to create the working data section  30 , the sector index table  31  and the duplicate data section  34 . At the same time, the disk space allotted to each section is defined. It shall be noted that data manipulation in the working data section  30 , the sector index table  31  and the duplicate data section  34  of the data protection device  10  still uses the conventional data read/write signals. 
   Referring to  FIG. 3 , the data pattern existing in the working data section and the sector index table is shown. The operating system has ‘FF’, ‘00’, ‘15’, ‘A1’, and ‘B0’ written into sectors  30 A to  30 E, while the sectors  30 F to  30 I are still empty at this point. 
   When the operating system is about to write data into a certain sector of the working data section  30 , such as the data content in sector  30 A, the marking unit  20  is to check and mark the data flag  32  in the sector index table, which indicates whether valid data are present in the sectors  30 A to  30 F. If the sector  30 A has data content ‘FF’, then the data flag  32  of respective sector shall be marked as ‘1’ indicating valid data are present in the sector  30 A, but if the sector  30 B does not have any data, the data flag  32  of respective sector in the sector index table  31  shall be marked as ‘0’. 
   Referring to  FIG. 4 , the data pattern in the duplicate data section is being derived from associated data pattern in the working data section and sector index table shown in  FIG. 3 . When the archiving procedure is invoked, the archiving unit  22  first checks the data flag  32  of a certain sector marked in the sector index table  31  before the data in the working data section  30  is copied to the duplicate data section  34 , such as the sector  30 B with data flag status ‘0’ which indicates the sector  30 B does not have any data, so the archiving procedure will skip over the sector to the next one, thus one sector is saved for more meaningful data. The associated data flag value is also copied to the duplicate data section  34  as shown in  FIG. 4 , but it is not necessary to put the data flags  32  in front of regular data as demonstrated in the present example. 
   The present invention is characterized in that the disk space used by the working data section  30  and the duplicate data section  34  does not have to be equal, unlike the prior art technique. Since the storage media interface used by the data protection device  10  is not limited to supporting two disk drives, the present invention is able to support any type of storage media interface, so the number of disk drives being connected can be changed for different system configurations. 
   The marking unit  20  of the data protection device  10  is used to record the data flags  32  of all sectors used by the working data section  30  in the sector index table  31 , so that, for example, sector  30 B with no data shall be skipped over in the archiving procedure. This can also explain why the disk space used by the working data section  30  and the duplicate data section  34  does not have to be the same. 
   Referring to  FIG. 5 , the second embodiment of the invention is presented, in which a data recovery unit  24  is included in the data protection device  10 . If some of the data saved in the data protection device  10  are corrupted or when the data storage device is attacked by a computer virus, the user is able to invoke the data recovery unit  24  to restore the original data in the working data section  30  using the data copy from the duplicate data section  34 . 
   When the data recovery procedure is invoked, the data recovery unit  24  uses the data flags  32  of certain sectors marked in the sector index table  31  as shown in  FIG. 4  to restore the data originally written in sectors  30 A,  30 C,  30 D, and  30 E of the working data section  30 , using the data copy in the duplicate data section  34 . Since the data flags  32  in the sector index table  31  indicate that the sector  30 B does not have any data, the data recovery unit  24  shall fill the sector  30 B of the working data section  30  with blank data ‘00’ in the data recovery procedure. 
   Referring to  FIG. 6 , the third embodiment of the invention is presented. If the data content in the sectors  30 F to  30 I of the working data section  30  is arranged as ‘14’, ‘15’, ‘00’, and‘17’, that means the sector  30 H does not have any data. In this case, the data flag  32  originally used in the first embodiment is to add a new data flag entry  40  with the data arrangement‘1, 1, 0, 1’. Therefore, in case the user sets up another data protection node, the archiving unit  22  is first to check on the data flags  32 ,  40  in the sector index table  31  and then data saved in sectors  30 A to  30 I in the working data section  30  are copied to the duplicate data section  34 , together with associated data flag values as shown in  FIG. 6 . 
   Using the same data manipulation, in the event of a computer disaster, data need to be restored to the working data section  30 , the data recovery unit  24  is first to check on the data flags  32 ,  40  in the sector index table  31 , and then respective data in the duplicate data section  34  are copied to the sectors  30 A to  30 I of the working data section  30 , and the data in the working data section  30  before the disaster occurs. The data flags  32 ,  40  of the respective sectors are also restored to the original values in the sector index table  31 . 
   Referring to  FIG. 7 , the fourth embodiment of the invention is presented, in which a disk space tracking unit  70  is included in the data protection device  10 . The function of the disk space tracking unit  70  is to collect updated information of remaining disk space and occupied disk space in the working data section  30 , the sector index table  31 , and the duplicate data section  34 . Each time when the archiving unit  22  is invoked to copy data into the duplicate data section  34 , the disk space tracking unit  70  is first to be consulted to obtain an updated information about the disk usage in order to prevent overwriting of any valid data. Also, through the service of the disk space tracking unit  70 , the user is able to obtain useful information about the disk usage in the working data section  30 , the sector index table  31  and the duplicate data section  34  continuously for other applications. 
   Referring to  FIG. 8 , the fifth embodiment of the invention is presented, in which a backup interface  26  is included in the data protection device  10 . This backup interface  26  enables data line connection between the data protection unit  10  and the data backup device  28 , so that the data protection unit  10  is able to retrieve data from the data backup device  28 . In case the disk space allotment unit  18  has assigned multiple sectors of the data backup device  28  to the duplicate data section  34 , the archiving unit  22  is able to use additional disk space on the data backup device  28 . 
   The backup interface  26  is to use a suitable bus interface, such as the small computer system interface (SCSI), the fiber channel interface (FC), the peripheral component interconnect (PCI), the flash card interface, the serial storage architecture (SSA), the integrated device electronics (IDE), the universal serial bus (USB), IEEE 1394, the personal computer memory card international association (PCMCIA), serial ATA (SATA), and parallel ATA (PATA). 
   The data backup device  28  is to use a suitable storage medium, such as a hard disk, an optical disk burner, a ZIP disk drive, a MO disk drive, a tape drive, and a card reader. Therefore, the data backup device  28  can be replaceable storage media, which enables the user reference points, such as certain hour or date, for data copying and restoration operation. However, it shall be noted that the disk space in the duplicate data section  34  shall be adjusted each time after the storage medium in the data backup device  28  is replaced so as to reflect the disk space used thus far and the disk space still remaining. 
   This innovative use of a sector index table containing data flags in the present invention enables the user to use less access time and disk space usage to accomplish data archiving and data recovery. Also, another feature of the data protection device is a multi-node data protection using the multiple selection of data reference point. 
   Although the present invention has been described with reference to the preferred embodiments thereof, it is apparent to those skilled in the art that a variety of modifications and changes may be made without departing from the scope of the present invention which is intended to be defined by the appended claims.