Design And Implementation Of Disk Isolation System Supporting Multi-Reverting Points

As one of the main storage mediums, hard disk's security is getting more and more attentions. How to prevent the disk data from being destroyed or filched by viruses from the Internet and how to revert the data which are mistakenly modified or deleted efficiently to minimize the hidden trouble are of great importance in the information security field. This thesis made contributions in following aspects.1. A new principle of isolating and reverting of hard disk data was proposed after thoroughly discussing the techniques of multiple isolation areas and multiple reverting points in one disk. We kept a work mapping table, which was used to convert the reading and writing addresses, to fulfill the function of multiple isolation areas setting in one disk. Furthermore, the function of setting multiple reverting points was completed through saving the work mapping table and storing the redundant information.2. A new approach for allotting and recycling the free disk space was presented after the researching on the principle of files'reading and writing operations and the management in the FAT32 and NTFS file systems.3. A method for preventing memory from being covered was implemented for the buffer that was set in memory may be covered in the real mode.4. The controlling over reading and writing operations on the disk data in the real mode was implemented by researching on BIOS INT 13H redirecting technique.5. The technique of disk filter driver was thoroughly studied to accomplish the controlling over reading and writing operations on the disk data in the windows.This thesis designed and implemented a disk isolation system supporting multi-reverting points, and the testing for the system was presented. According to the results, the system has good performance in stability and can provide isolating and reverting functions for the disk data. Moreover, the system has low overhead both in time and space and is up to the demand.