Network: constant activity, why ??

[Vincent Trouilliez]

Hello, network gurus out there,


Problem: currently my internet connection is quite slow 1Mbps down and 128Kbps up. I just got informed that in a week or two, my ISP, for no price increase, will speed things up a lot: 30Mbps down and 1Mbps up. BUT, they also introduce a quota, and I must not use more than 30GB of traffic per month.
Now, 1GB per day is plenty enough for what I do... BUT (yes another "but" ;-), when I open up the system monitor (System->Administration->System Monitor), I notice that there is always some traffic trickling downstream, for NO APPARENT reason ! I mean, I just start the machine, don't even start my e-mail client nor my web browser or anything ! :-O
It's trickling at about 2 KB/s typically (but with random spikes of higher values !), which seemed harmless until I realised it adds up to nearly 200MB per day ! So that's a good chunk of the allowed 1 GB that's gone ! :-O

Now, that still leaves 800MB per day for actual e-mail, browsing, etc, so that's enough I think, but still I would LOVE to know what the hell in the system (Fresh Ubuntu Dapper i386, Gnome) is consuming my bandwidth and why, and if it can be stopped in case it happens to be some under the hood service I happen to not need.

Thanks in advance for shedding some light :-)


Regards,


--
Vince