Why P2P traffic is a problem for fixed networks while has very limited impact on mobile lines?
This fact was published by Allot communications (you can find a very interesting report here and references to these report here) some weeks ago and I think it is mainly driven by the commercial structure of fixed and mobile services.
Most of fixed broandband access are based on flat-rate fees, while mobile services tend to be limited depending on the traffic volume.
What does this mean? This means that bandwidth or better to say traffic volume on fixed broadband has no cost, while on mobile services it do cost to the end user. And this has a lot of implications to the network.
Here in Spain we have a problem and this is that some users have their P2P servers downloading movies all day. They download everything… even though it is unlikely that they will be able to watch 20% of the content they download. They are creating digital libraries of media content.
This is not good for the rest of the users, because this behavior affects the commercial offers of network operators, both in price and in performance.
In price, because we pay for the network utilization a very limited group of users take advantage of and in performance because one of the strategies used by network operators to limit P2P is to limit upstream.
Thus, I really believe that a much better approach to develop broadband in Spain would be to offer more symmetric connections (with xDSL technologies it is possible) but limiting the traffic volume so the users of P2P think twice whether it is worth the download.
This approach also preserves one of the fundamentals of the Internet, which is network neutrality.