Data Integrity of a download?

[wazel45]

Hello,

I don't usually download torrents, i wanted to ask..

With utorrent, what happens to a download if say:

My connection is suddenly cut off and i resume

or

My download speed goes as low as 0.3 kB/s for just a moment?

Is there any loss in data integrity of the download if these happen?

[Saribro]

Every completed piece is checked against the hash (which is stored in the .torrent) for correctness. So, unless you have data corruption -after- µTorrent has written the pieces to disk (broken hardware, media indexers that change file tags,...), data integrity is pretty much certain.

That said, if the original torrent was made with bogus data, you'll end up with bogus data too, but you can be certain that is an identical copy of the original bogus data .

[wazel45]

I see, so what is this hash? In my download information im getting a

"Wasted:184 kB (0 hashfails)"

What does this mean?

[DreadWingKnight]

That means that 184kbyte worth of data was downloaded twice, none of which was because of data segment validation failures.

[wazel45]

Why was it downloaded twice then?

Please excuse me for sounding like a noob. Like i said i dont usually use torrents =D

So 'Hashfails' basically means a failure in data validation/integrity when checked against the hash right?

[DreadWingKnight]

That data is downloaded twice for a number of reasons including the multiple-request attempts at the end of a torrent's download procedure and peers disconnecting mid-block.

When uTorrent says 100% completed, it means that ALL pieces have passed validation.

[Switeck]

Last piece may have been "fed" by 3+ peers/seeds feeding to you at once. There's often overlap.

[wazel45]

"When uTorrent says 100% completed, it means that ALL pieces have passed validation"

- Ok so 'validation' means the downloaded data checked against the hash has passed... thus being identical to the original and that there hasn't been any loss of data integrity right?

That's my main concern.

[DreadWingKnight]

That's right.

[wazel45]

Alright. thanks for the info.