File-chunk identification possibility

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1

From @shalnoff on Fri Dec 25 2015 09:13:36 GMT+0000 (UTC)

Is it possible to identify the file that chunk is owned (and vice versa)?


Copied from original issue: https://github.com/ipfs/faq/issues/85

2

From @RichardLitt on Thu Mar 10 2016 19:02:19 GMT+0000 (UTC)

Iā€™m not sure. @diasdavid @whyrusleeping what do you think?

3

From @whyrusleeping on Mon May 02 2016 19:37:32 GMT+0000 (UTC)

@shalnoff could you clarify what you mean?

4

From @diasdavid on Tue May 03 2016 18:28:18 GMT+0000 (UTC)

@shalnoff if your question is ā€˜given a chunk, can I identify the file it belongs to, without any other information at allā€™, the answer is no, you canā€™t, that would violate the principle of a DAG.

5

From @mcast on Tue Sep 13 2016 20:38:27 GMT+0000 (UTC)

> @shalnoff if your question is ā€˜given a chunk, can I identify the file it belongs to, without any other information at allā€™, the answer is no, you canā€™t, that would violate the principle of a DAG.

I would only add, ā€œā€¦unless you have some extra informationā€. Would these methods work?

  1. fetching the chunkā€™s data, recognising some distinctive feature of its encoding. e.g. itā€™s plain text, or gzipped text with a convenient block start; take five words and put them into a search engine to get the original.
  2. enumerate (#155) a large enough swathe to discover (some of) the chunkā€™s parents.
  3. be in possession of some kind of reverse-lookup index, constructed from such enumeration

In a different chunking system, which could ride ipfs it is by design impossible to identify chunks.

6

From @shalnoff on Wed Sep 28 2016 21:35:28 GMT+0000 (UTC)

Clear, thatā€™s what Iā€™d like to clarify. Thank you (sorry for late reply)