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Altnet Threatens P2P Companies Over File Hash Patents
devil_doll writes "I saw over on p2pnet that Altnet is trying to 'mug' a number of P2P companies with seemingly bogus patents. One of them is titled 'Data processing system using substantially unique identifiers to identify data items, whereby identical data items have the same identifiers,' and appears to be nothing more than a simple hash table."
What, from my reading, the patented technology does, is find dupes, and reassign the "truename." to the dupes, whether remotely or locally.
For example, you have foo.txt. Someone copies foo.txt to bar.txt, without changing any of the data contained within foo.txt (it's some pretty piece of ascii art, just to keep you amused for a moment....).
This thing would keep tables on the files, and when run, would go back and rename bar.txt to foo.txt if wanted, or could delete bar.txt if the user requested.
But still, it's pretty obtuse. Even as someone with legal training, and a computing background, I had a hard time making out exactly what they were patenting.
A link to the Washington Post article mentioned in the p2pnet article would be nice, too, if someone can find it...?
No, it's a real patent.
But where the problem lies is that there's no requirement for the applicant to do due dilligence in seeking out prior art -- that's the job for the patent office. As many recent events have shown, they're not doing a very good job of it. So, the patent gets granted. Then it's a real pain to get it overturned, obvious prior art or not.
I had to look this up :D
y
http://dictionary.reference.com/search?q=tautolog
tautology Audio pronunciation of "tautology" ( P ) Pronunciation Key (tô-tl-j)
n. pl. tautologies
1.
1. Needless repetition of the same sense in different words; redundancy.
2. An instance of such repetition.
2. Logic. An empty or vacuous statement composed of simpler statements in a fashion that makes it logically true whether the simpler statements are factually true or false; for example, the statement Either it will rain tomorrow or it will not rain tomorrow.
I started a thread on the P2P-Hackers mailing list abuot this, and a number of people have responded with examples of prior art and other relevant information. You can find the post that starts this thread here.
isn't isopropyl alcohol/isopropanol simply rubbing alcohol? Get it cheap at the drug store.
Well, actually, that would be a pleonasm, because 'bogus' and 'patent' aren't the same word type. :)
:)
Flame ahead
There are certainly hundreds of cases of prior art, and Tripwire is probably one of them. It computes and maintains a database of hashes for all the files on a file system to check for intrusions and corruption. The wiki entry says it first surfaced in 1992.
don't use rubbing alcohol.
Use a consumable grade grain alcohol. It is much less toxic.
In NH you can get everclear which is 99% alcohol.
Also, you don't just "shake" the mixture.
You shoudl slowley (veeeeeeeeerrrrrrrrrryyyyyy) slowley heat it to get the THC to dissolve in the alcohol.
NOt to hot or it evaporates though.
This is a common thing in US patent law. A patent in the US isn't really granted until it is upheld by a court. Often, one company will target a smaller, weaker company with a similar product for patent infringement on the hopes that they can beat the company in court, have their patent upheld thereby, and then go after bigger fish with requests for royalties.
I was once involved in a patent case where a medium sized company was suing a smaller company over their use of "laser etched checking fixtures" (an industry standard item). The larger company's patent documentation was so vague that part of it actually seemed to be claiming the invention of the Cartesian coordinate system and the idea of graph paper.
It was laughed out of court but just think who they could have sued if that patent would have been upheld.
The Article
A hash-table is a data-structure, not a 'data processing system' (a system that performs operations on data-structures).
I think a better example of prior 'art' would have been something like Token Ring Networks, a Relational DBMS, the TCP/IP Suite, etc...
Not necessarily :-)
The "counting argument" can be used to show that no compression algorithm can hope to reduce the size of every file. Hence most (all?) compression programs will, from time to time, have to store an uncompressed version of the input file, and will thus have to have some mechanism for signalling to the decompressor that they have done so. Even if this "flag" is one bit long it will still represent an increase in size compared to the input file.
Real-life compression programs will of course be storing other information in the output file (e.g. original filename, size/checksum) so in practice we are talking about several bytes increase rather than one bit.
Note it's still possible to create a hash that is unique (like the above) but retrieving the content of the file from it (decompressing) is impossible. Just take your .bz2 "hash" and encrypt it, using its own MD5 as password.
Not actually impossible, just decidedly time-consuming. As mentioned above, a .bz2 file will have a recognizable internal structure. It's then just a matter of brute-forcing the decryption until a file of the appropriate format appears. With 128 bits of MD5 "key" this will take quite a while, but it's theoretically possible.
A number of reasons
1) Suppose I give you a DVD containing some software. 32 thousand million '0's and '1's. There's no objective way to tell whether the DVD infringes the patent.
2) It stops me from teaching my children how to program computers.
3) A general purpose computer will run any bit string. Your algorithm is a bit string; one of those that a general purpose computer will run. That's prior art.
4) You have to describe your algorithm well enough so that after the patent expires, the rest of us will be able to use it for free. Are you sure you did so ?
5) Suppose I give you a DVD. 32 thousand million '0's and '1's. You have a magic way of telling whether it infringes, and you say it does. Then it turns out that the DVD was cut before your patent was granted. Prior art, your patent goes poof.