Are you connected to Terranet or Ogero? If you access your Terranet webpage account, what is written over there?
OK: Manipulate the electricity cut off state:
1-Connect to your ADSL modem directly with a cable.
2-Check your
external IP addresse to Terranet; under ADSL connection menu or whatever, and save that IP in a notepad or whatever.
3-Cut off the power from your home.
4-Do multiple
ADSL reconnections and test the ping to
www.google.com on each attempt. Compare the external IP addresses and the ping results.
-If the external IPs change: your getting reconnected when the electricity goes off even though it is connected to a UPS
, and if the pings varies much: it is your pool of IPs having highly different pings when you reconnect each time.
-Otherwise: your networking devices are causing highly different pings.