History:
I'm currently in Korea and Koreans have quite a few differences in the infrastructure of the internet which makes the entire country use Windows XP only. This deals with security protocol as I remember reading an article, anyways, I doubt that that has anything to do with my problem.

My problem:
When my computer (Vista 32) sits idle on the internet for a period of time, the internet stops working until i restart the computer or re-log into the computer.

Setup:
This could be a simple fix because I have disabled a few services, many are on manual however. When I was in America I always connected to the internet through a network, now i'm connected directly via a modem.

The problem is annoying and any insight as to why it happens or what can be done about it would be much appriciated.

Much obliged, Kenny.