Ndnfs » History » Version 4
Wentao Shang, 11/19/2015 03:14 PM
| 1 | 1 | Wentao Shang | NDNFS: an NDN-friendly file system |
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| 2 | ===== |
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| 3 | |||
| 4 | NDNFS Metadata format |
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| 5 | ----- |
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| 6 | 2 | Wentao Shang | |
| 7 | NDNFS uses metadata to facilitate the discovery of directory contents, file versions and segments. |
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| 8 | The format of metadata is specified using "Google Protobuf":https://github.com/google/protobuf/. |
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| 9 | 3 | Wentao Shang | Currently two types of metadata are defined: directory metadata and file metadata. |
| 10 | |||
| 11 | Directory metadata |
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| 12 | ----- |
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| 13 | |||
| 14 | The directory metadata helps the client navigate through the NDNFS hierarchy. |
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| 15 | The metadata packet contains a list of metadata entries. |
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| 16 | Each entry specifies the path of the entry and its entry type (file, directory, symlink, etc.). |
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| 17 | |||
| 18 | message DirInfo |
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| 19 | { |
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| 20 | required string path = 1; |
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| 21 | required int32 type = 2; |
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| 22 | } |
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| 23 | |||
| 24 | message DirInfoArray |
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| 25 | { |
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| 26 | repeated DirInfo di = 1; |
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| 27 | } |
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| 28 | |||
| 29 | |||
| 30 | File metadata |
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| 31 | ----- |
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| 32 | |||
| 33 | The file metadata contains at least three attributes: size, total number of segments and current version number. |
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| 34 | More attributes can be added in the future. |
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| 35 | |||
| 36 | message FileInfo |
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| 37 | { |
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| 38 | required int32 size = 1; |
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| 39 | required int32 totalseg = 2; |
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| 40 | required int32 version = 3; |
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| 41 | } |
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| 42 | |||
| 43 | |||
| 44 | NDNFS Metadata Protocol |
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| 45 | ----- |
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| 46 | |||
| 47 | TBD. |
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| 48 | 4 | Wentao Shang | |
| 49 | For more information, please refer to http://named-data.net/wp-content/uploads/2014/10/ndn-tr-27-ndnfs.pdf |