Is there any software or tricks which log in automatically?

[chandra]

If you mean just starting browser of your choice, then do this . This is for windows 7. switch on internet
Go and create a short cut key for your browser.
Then Click Start, All programs and then to Startup Folder.
You just right click and select open all users, you get a screen, just copy the shortcut of your browser to automate the browser start up at the Windows Start.
Your question is ambigious. Some times work and other times.
Whenever you need internet connection, you have to click the internet explorer or other browser, the connection is established provided you are connected to the internet.When you close it, your internet is getting disconnected.