Hi Tobias,

the first *** line means that the router from your isp dont allows/dont respond to this command -.-
for me it looks like you run in to a slow down advice
from your isp like Estel mention
caused by

a) high traffic in your network note
b) low singal caused by some frequency interferers
c) somethink i have missed to think about^^

i would email my isp to ask if the problem could be fixed.
somethink like:

i have some latence problems with your (data-plan/3G)
normaly my latence looks like this:
traceroute output

if the problem happens it looks like
(time/date you have trouble)
traceroute output

Because i need the normal latence for my work i would like to know if you could offer me a solution to get this problem fixed.

Warm greetings to you...

greetings from germany
Hoga

ps: just to check make a trace from your laptop at the time the problem happens so u can see the n900 is responding fine

to do that open "cmd" dos-box and type "trace google.com"
the first ip sould be your n900
responding in the same time that it takes without the problem^^