For testing the internet

Windows 2000 / Windows XP:
To open the MSDOS-commandline, write command "ipconfig",
to ask for a new ipadress: "ipconfig /renew"

To check for the network working:
Start the msdos-commandine, and write in the command "ping "gateway".

It looks like something like this:
Bø:
Pinger 128.39.124.1 med 32 byte data:
Svar fra 128.39.124.1: byte=32 tid<10ms TTL=255

Notodden:
Pinger 128.39.128.1 med 32 byte data:
Svar fra 128.39.128.1: byte=32 tid<10ms TTL=255

Porsgrunn:
Pinger 128.39.136.1 med 32 byte data:
Svar fra 128.39.136.1: byte=32 tid<10ms TTL=255

For testing the internet working:
C:\>ping 128.39.196.1
Pinger 128.39.196.1 med 32 byte data:
Svar fra 128.39.196.1: byte=32 tid<10ms TTL=255