Method and apparatus for identifying a piece of content

1. A content system, comprising:

a computer comprising:

a content store for storing a piece of content; and

a content identifier generator, wherein the content identifier generator comprises:

a gathering unit that gathers two or more attributes for a piece of content, wherein one of the two or more attributes is a size of the piece of content; and

a generator unit that generates a deterministic identifier for the piece of content based on the two or more attributes, wherein the deterministic identifier comprises the size of the piece of content and a hash value of at least one of the two or more attributes, wherein the same deterministic identifier is generated each time the generator unit generates a deterministic identifier for the piece of content, and wherein validity of the deterministic identifier is independent of the physical location of the piece of content;

wherein the computer includes a hardware processor.

2. The system of claim 1 , wherein:

the piece of content is movable on the computer without affecting the validity of the deterministic identifier;

the content system further comprises an index maintaining deterministic identifiers generated by the generator unit;

the two or more attributes further comprises a title of the piece of content; and

the deterministic identifier further comprises a version of the title of the piece of content.

3. The system of claim 1 , wherein:

the piece of content comprises a digital song; and

the two or more attributes further comprises one or more of a title of the digital song, an artist of the digital song, and an album associated with the digital song;

wherein the deterministic identifier further comprises a version of the title of the digital song, and wherein the version of the title of the digital song includes only a portion of alphanumeric characters included in the title of the digital song, such that the version of the title of the digital song is shorter than the title of the digital song.

4. The system of claim 1 , wherein:

the piece of content comprises a digital video; and

the two or more attributes further comprises one or more of a title of the digital video, an artist of the digital video, and an album associated with the digital video;

wherein the deterministic identifier further comprises a version of the title of the digital video, and wherein the version of the title of the digital video includes only a portion of alphanumeric characters included in the title of the digital video, such that the version of the title of the digital video is shorter than the title of the digital video.

5. The system of claim 1 , wherein the deterministic identifier is 36 bytes long.

6. The system of claim 1 , wherein at least one of the two or more attributes is located in metadata associated with the piece of content.

7. The system of claim 6 , wherein the metadata further comprises an MP3 ID3 tag.

8. The system of claim 1 , wherein:

the content store stores different types of digital content; and

the content identifier generator is further configured to generate deterministic identifiers for different types of digital content.

9. The system of claim 1 , further comprising:

a mobile device;

wherein deterministic identifiers generated by the generator unit are maintained in a first index on the computer and a second index on the mobile device;

wherein the validity of the deterministic identifiers are maintained across each index of the system; and

wherein the content identifier generator encodes the two or more attributes for the piece of content.

10. A method for generating an identifier for a piece of content, comprising:

gathering, by a content identifier generator, two or more attributes for a piece of content, wherein one of the two or more attributes is a size of the piece of content; and

generating, by the content identifier generator, a deterministic identifier for the piece of content based on the two or more attributes, wherein the deterministic identifier comprises the size of the piece of content and a hash value of at least one of the two or more attributes, and wherein the same deterministic identifier is generated each time the generator unit generates a deterministic identifier for the piece of content;

wherein the content identifier generator resides on a computer that includes a hardware processor, and wherein validity of the deterministic identifier is independent of the physical location of the piece of content.

11. The method of claim 10 , wherein:

the piece of content is movable on the computer without affecting the validity of the deterministic identifier;

the computer further comprises an index maintaining deterministic identifiers generated by the content identifier generator;

the two or more attributes further comprises a title of the piece of content; and

the deterministic identifier further comprises a version of the title of the piece of content.

12. The method of claim 10 , wherein:

the piece of content comprises a digital song; and

the two or more attributes further comprises one or more of a title of the digital song, an artist of the digital song, and an album associated with the digital song;

wherein the deterministic identifier further comprises a version of the title of the digital song, and wherein the version of the title of the digital song includes only a portion of alphanumeric characters included in the title of the digital song, such that the version of the title of the digital song is shorter than the title of the digital song.

13. The method of claim 10 , wherein:

the piece of content comprises a digital video; and

the two or more attributes further comprises one or more of a title of the digital video, an artist of the digital video, and an album associated with the digital video;

wherein the deterministic identifier further comprises a version of the title of the digital video, and wherein the version of the title of the digital video includes only a portion of alphanumeric characters included in the title of the digital video, such that the version of the title of the digital video is shorter than the title of the digital video.

14. The method of claim 10 , wherein the deterministic identifier is 36 bytes long.

15. The method of claim 10 , wherein at least one of the two or more attributes is located in metadata associated with the piece of content.

16. The method of claim 15 , wherein the metadata further comprises an MP3 ID3 tag.

17. The method of claim 12 , wherein:

the content identifier generator generates deterministic identifiers for different types of digital content.

18. The method of claim 10 , wherein:

deterministic identifiers generated by the content identifier generator are maintained in a first index on the computer and a second index on a mobile device;

the validity of the deterministic identifiers are maintained across each index; and

the content identifier generator encodes the two or more attributes for the piece of content.

19. A content system, comprising:

a content store for storing one or more pieces of content and one or more unique deterministic content identifiers, wherein each unique deterministic content identifier corresponds to a piece of content; and

a content identifier generator that generates a corresponding unique deterministic content identifier for each piece of content based on two or more attributes for the piece of content, wherein the same unique deterministic content identifier is generated each time the content identifier generator generates a unique deterministic content identifier for the piece of content;

wherein each unique deterministic content identifier corresponding to a piece of content comprises a size of the piece of content and a hash value of at least one attribute of the piece of content;

wherein the content store resides on a computer that includes a hardware processor; and

wherein validity of the deterministic identifier is independent of the physical location of the piece of content.

20. The system of claim 19 , wherein:

each piece of content further comprises one of a digital song and a digital video.

21. The system of claim 20 , wherein:

for a piece of content comprising a digital song, attributes for the piece of content comprises one or more of a title of the digital song, an artist of the digital song, and an album associated with the digital song, wherein a unique deterministic content identifier corresponding to the piece of content further comprises a version of the title of the digital song, and wherein the version of the title of the digital song includes only a portion of alphanumeric characters included in the title of the digital song, such that the version of the title of the digital song is shorter than the title of the digital song.

22. The system of claim 20 , wherein:

for a piece of content comprising a digital video, attributes for the piece of content comprises one or more of a title of the digital video, an artist of the digital video, and an album associated with the digital video, wherein a unique deterministic content identifier corresponding to the piece of content further comprises a version of the title of the digital video, and wherein the version of the title of the digital video includes only a portion of alphanumeric characters included in the title of the digital video, such that the version of the title of the digital video is shorter than the title of the digital video.

23. The system of claim 19 , wherein:

each unique deterministic content identifier is 36 bytes long;

the content store stores different types of digital content; and

attributes for each piece of content are encoded.