Unpredictable. Unfocused. Just like life.

Mark Evans asked an interesting question today:

One question is how Shaw is determining competitive voice packets - likely using technology from Ellacoya - and whether it's "shaping" other kinds of traffic on its network.

In a previous life I did a fair bit of work with policy-based network management. Strangely enough I even interviewed with Ellacoya who were just a short drive from me.

There are several ways to shape traffic, such as by IP address, by port, or by using deep packet filtering to examine the packets. Given that it is a simple task to change IP addresses or ports, deep packet filtering is the most effective tool in determine the type of traffic for filtering purposes. However, encrypting the traffic would make it very difficult to determine the type of traffic, and therefore the ISP would have much more difficulty trying to throttle the traffic.

Of course Wikipedia has a page on the subject of protocol encryption, and even a list of bad ISPs that throttle your traffic.

What I wonder is how these ISPs can justify discriminating against some forms of traffic. I certainly don't recall that in the advertisements when I was signing up. After all, this is not illegal. The ISPs are doing it for their convenience.And in the case of Rogers, who are throttling Bittorrent traffic, their network is not improving. In fact it seems to be getting slower.