I have a ADSL connection to the internet at home. I suspect the speed of my connection of being below what I should normally get, but I don't know exactly what cause the slowdown. Is it:

- The internet configuration in Windows that is not well defined
- My modem (Efficient Networks, SpeedStream 5260)
- My phone line (yes, I am connected with a 30' phone line extension...)
- My ISP
- or it's just my imagination

What should I look for? Is there a tool that would help me pinpoint the problem?

TIA