This is happening for a while now. When I am on the internet, it's fine but after few minutes it disconnects and comes back after I do to connection diagosing thing it suggests. This is happening a lot now and it is really annoying. Please, are there any suggestions on how I can fix this? It'll really help. THANKS!

Have you contacted the phone company to see if it's your phone line? HAve you contacted your net provider? I used to have dial up that would just mysteriously disconnect me every so many minutes. Only after several years of this did the phone company finally figure out my home location had two phone lines (even though I had only one phone line the previous owners had 2 lines) and once they officially disconnected the second line to my home did my problem disappear.

Do you have dial up or broadband?

Knowing a little bit more about the situation can help us help you. What type of internet do you have? Eg: dial-up, DSL, Cable, etc...
How are you connecting to the internet? Wireless, Ethernet, Ad-Hoc, etc...

Knowing more can help us narrow down any possible causes.

Are you using WIFI or wired connection? Do you notice any lights that change on your modem when this happens? Does this only happen on one device, or does it happen to all devices you have connected to that one internet connection?