While I have been browsing the net..I came accross a very interesting presentation from BT telecom on what causes ADSL Interference. Have a look at the presentation below..
Download PDF: Here
Cacti is a great graphing tool for monitoring your network traffic, and especially for capacity planning. However what if the links you utilise are greater than 100mbit? Cacti by default will only graph up to 120mbits with the graphs since they are only 32bit graph counters. In order to graph more than 120mbits of bandwidth 64bit counters are required. I have included as part of this post a XML import file for cacti which allows you to use 64bit counters but with Total Bandwidth as well recorded from the graphs. Thanks to a friend of mine (Mr DS) for finding this on the cacti forums. (http://forums.cacti.net/about4160-0-asc-0.html)