Which is the culprit? Internet connection disappears

[Maurice2]

My Windows XP computer is connected to a router which is itself connected to a cable modem. All connections are wired.

I can be on the Internet for long hours and never experience a disconnection.
However, if I disconnect from the Internet and leave my computer on (hard disc on) for several hours without touching it, when I return and try to connect to the Internet I very often cannot connect, no matter how many times I try. Message I get is "cannot find server." If I then re-start the computer, connection to the Internet is made flawlessly. In other words, I need to re-start the computer and everything works fine.

Which is the culprit? My computer, the router or the cable modem? Is there a way of determining where the problem is and how to solve it?

Many thanks.

 

[Hairy_Lee]

do you think there might be a sleep mode thats shutting the router down when you're disconnected from it?
if so i would suggest that restarting the computer is sending a signal to the router bringing it out of its sleep mode

 

[lee101]

Also try pinging the router when you cannot access the internet (start>run>cmd [enter] ping 0.0.0.0 , replace 0.0.0.0 with your routers IP address, and then with you modems) to see if you get a response from any of them, if you get from one but not the other this will narrow down to what the problem could be

 

[Maurice2]

do you think there might be a sleep mode thats shutting the router down when you're disconnected from it?

I don't think so, because I can see that the router is still active when I cannot connect to the Internet: I have an Internet phone which is also connected to the router and it always works -- the light on the router keeps on flashing. Unless the sleep mode only affects the computer. I'll research this, although I don't recall an option to that effect. The router, by the way, is Netgear RP614 v2.

 

[Maurice2]

Also try pinging the router when you cannot access the internet (start>run>cmd [enter] ping 0.0.0.0 , replace 0.0.0.0 with your routers IP address, and then with you modems) to see if you get a response from any of them, if you get from one but not the other this will narrow down to what the problem could be

Thanks for this advice. While my connection to the Internet is working, I have now pinged both the router and the cable modem and they both respond. When there is a new failure, I'll try each one again.