Method and apparatus for data protection
Embodiments of the present disclosure relate to method and apparatus for data protection. For example, there is provided a computer-implemented method. According to the computer-implemented method, it only needs to read the changed data to be protected rather than the entire data to be protected during the procedure of generating a redundant data portion for the changed data to be protected.
1. A computer-implemented method, comprising:
in response to determining a change in a first data segment of a first data portion, obtaining a changed first data segment and a second data portion, the first data portion including raw data to be protected, and the second data portion including redundant data generated based on the raw data;
generating a second data segment, bits in the second data segment indicating whether corresponding bits in the first data segment and in the changed first data segment are identical;
obtaining a third data portion by expanding the second data segment, the third data portion having a same length as the first data portion;
generating redundant data for the third data portion as a fourth data portion;
generating a fifth data portion, bits in the fifth data portion indicating whether corresponding bits in the second data portion and in the fourth data portion are identical;
updating the second data portion with the generated fifth data portion.
2. The method of claim 1 , wherein generating the second data segment comprises:
applying an exclusive-or operation to the first data segment and the changed first data segment.
3. The method of claim 1 , wherein obtaining a third data portion by expanding the second data segment comprises:
expanding the second data segment with a zero bit.
4. The method of claim 1 , wherein generating the fifth data portion comprises:
applying an exclusive-or operation to the second data portion and the fourth data portion.
5. The method of claim 1 , wherein the second data portion is generated by performing an erasure code operation on the first data portion.
6. An electronic apparatus, comprising:
at least one processing unit; and
at least one memory coupled to the at least one processing unit and having machine executable instructions stored thereon which, when executed by the at least one processing unit, causing the electronic apparatus to perform acts including:
in response to determining a change in a first data segment of a first data portion, obtaining a changed first data segment and a second data portion, the first data portion including raw data to be protected, and the second data portion including redundant data generated based on the raw data;
generating a second data segment, bits in the second data segment indicating whether corresponding bits in the first data segment and in the changed first data segment are identical;
obtaining a third data portion by expanding the second data segment, the third data portion having a same length as the first data portion;
generating redundant data for the third data portion as a fourth data portion;
generating a fifth data portion, bits in the fifth data portion indicating whether corresponding bits in the second data portion and in the fourth data portion are identical;
updating the second data portion with the generated fifth data portion.
7. The apparatus of claim 6 , wherein generating the second data segment comprises:
applying an exclusive-or operation to the first data segment and the changed first data segment.
8. The apparatus of claim 6 , wherein obtaining a third data portion by expanding the second data segment comprises:
expanding the second data segment with a zero bit.
9. The apparatus of claim 1 , wherein generating the fifth data portion comprises:
applying an exclusive-or operation to the second data portion and the fourth data portion.
10. The apparatus of claim 1 , wherein the second data portion is generated by performing an erasure code operation on the first data portion.
11. A computer program product tangibly stored in a non-transient computer readable medium and including machine executable instructions which, when executed, cause a machine to perform the method according to claim 1 .
12. The computer program product of claim 11 , wherein the machine executable instructions, when executed, cause the machine to perform the method according to claim 2 .
13. The computer program product of claim 11 , wherein the machine executable instructions, when executed, cause the machine to perform the method according to claim 3 .
14. The computer program product of claim 11 , wherein the machine executable instructions, when executed, cause the machine to perform the method according to claim 4 .
15. The computer program product of claim 11 , wherein the machine executable instructions, when executed, cause the machine to perform the method according to claim 5 .
16. The method of claim 1 , wherein the first data segment is a first subset of the first data portion, the second data segment is a second subset of the third data portion, and the second data segment is surrounded by zero bits within the third data portion.
17. The method of claim 16 , wherein the first data segment and the second data segment occupy a same relative position within the respective first and third data portions.