A different level of impact

Loose thoughts by Bjorn Landfeldt

After the government released its report on Internet content filtering senator Conroy released a statement that the government will test P2P filtering as such tools currently exist. This is very interesting because the bar is raised considerably if this is the case.

In the report I did not raise and strong concerns with performance degradation at the ISP level when comparing HTTP requests to a blacklist. I believe the performance penalty can be significantly reduced by purchasing additional equipment and the ISPs can be compensated for such roll out. The current trials can actually answer some of the questions as to the performance penalty and cost to alleviate them in terms of additional equipment purchases.

However, with P2P filtering the situation is very different. In this case, the filtering system has to do deep packet inspection to figure out if something should be banned or not and this is very different to checking terminating address. The deep packet inspection will be used to try to identify what kind of content is accessed since in a P2P content distribution network end addresses are useless. This puts us in the realm of dynamic filtering which pretty much is the worst nightmare for the Australian ISP industry and necessarily will mean significant performance penalties for the Australian public. Even if some video in a bit torrent would be called "child abuse that is illegal in Australia and should be filtered by the government" a filter would have to perform analysis of this text to determine if the media should be filtered. Changing the name of this file to "daisies in summer" and the filtering system would have to analyse the content of the video itself to determine if it is illegal and should be blocked.

In addition to performance penalties, such system raises much stronger privacy concerns. Even if very little content would actually be blocked with such system, someone is really checking how Australian citizens are using their network connections.

It will be interesting to see how this will pan out.