Recently I had experienced disconnected from the internet too frequently.
Today morning I asked to help. It took more than 40 minutes by phone.
The agent checked the service and answered me. "Everything is good, If you power down and on you could keep connect"
I did whatever the agent request to me. But failed. Five minutes passed since the connection had restored I experienced the connection failed again.
I visited shaw customer center and swapped my modem.
Finally no more problem.
If anybody has same problem then I recomend you swap your modem.
It took money and time but problem was solve..