It seems the majority of throttling hardware companies are not up to the job only 2 out of 28 dared to allow publication of their test results.
http://arstechnica.com/news.ars/post/20080327-deep-packet-inspection-for-p2p-traffic-put-to-the-test.htmlDeep packet inspection (DPI), a technique for identifying the contents of individual data packets running across IP networks, has wound up at a messy intersection of competing interests.
Recently, Internet Evolution and the French equivalent of the RIAA attempted to perform lab tests on DPI hardware from a variety of vendors, and their effort produced a clear conclusion: most hardware vendors don't want you to know how well their equipment works.
The groups identified 28 different hardware makers and sent invites to all of them, allowing them to send engineers to ensure that the tests were performed fairly. All but five declined, and those that agreed reserved the right to refuse publication of the test results. Three of those vendors ultimately exercised that right. In the end, that meant that the test results for a grand total of two pieces of hardware wound up being published.
The biggest concern identified by the tests were the blind spots to some protocols and encryption techniques. The nature of P2P traffic has the ability to turn on a dime with a single software update, so the vendors may find their abilities challenged by the changing landscape.
This has been something known by P2p client builders for years, bittorrent clients utilise an encryption system as does most winmx traffic, although critically the file transfers themselves are not encrypted allowing winmx to be throttled, of course the only way around this is to add a layer of encryption to hide the known portions of the protocol they detect, this is of course something we may see in the fututre and folks are looking into this but for now we suffer, its nice to know that even with this weakness we can still enjoy the network due to poor implementation of DPI.
