Those who understand will be bored by this - but it might help some others make sense of what's going on.
There have been a lot of references here to "fake files". It turns out though it's much more evil than just planting some fake files. RIAA's hackers are taking advantage of a serious flaw in Kazaa's Hashing system to plant files which as far as the KAZAA search algorithms are concerned are identical to the real files. In reality parts of these files have been replaced with the 'orrible noise people are compaining about.
Because the bad files look the same to Kazaa as the good ones, and because when you download you usually download pieces of the file from multiple sources it's totally possible to get a corrupted piece with that 'orrible noise from one user that effectively ruins your whole download, and also creates yet another corrupted version of the file.
The defect in the Kazza protocols is that the identification of a song for the purposes of search is based on a "hash" : this is a large number computed by say adding all of the bytes of data in the song together and taking the last N digits or bits (in reality a fancier algorithm would be used). Kazza fucked up big time because they designed their hash algorithm to only include certain chunks of the file rather then every single byte and which chunks are included (and not) is very well known. So RIAA can fool the hash algorithm by trashing the bytes of the file which aren't included in the hash calculation. The trashed file will then have the same hash as the good file and will be downloaded as part of it.
What is really "nice" here is that this spreads corrupted sections of the file into new downloads due to Kazaa's multi-source feature - it spreads almost like a virus. Narsti!
The one thing that everyone can do now is to DELETE CORRUPTED FILES IMMEDIATELY!!!!
Beyond that, if KLite could download files into a non-shared directory then people could listen to the files to make sure they're OK before sharing them. KLite could implement features to support verifying files and moving them to shared.
In the end it may be necessary for Kazaa to fix their hash algorithm in which case software will probably need to be upgraded. Whether in the present legal climate they will feel safe fixing their bug is open to question.
And by the way, the defect that RIAA exploits is not inherently limited to any one bandwidth - if they aren't planting 192 bit rate files today, it's only because they ain't gotten around to it - they could.
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