Recently I upgraded from dial-up to broadband ADSL. I have a few questions regarding the ADSL connection:
1. Should I physically turn off my ADSL modem when the computer is turned off?
2. Will the ADSL modem still access the internet even if the web browser is not open?
3. When the computer is on and being used for word processing or spreadsheets, with the ADSL modem on, will it still access the internet?
4. Is it enough to exit the little ADSL icon on the taskbar situated on the bottom right hand side of the monitor?
The reason behind these questions is the usage rate limitations on my plan. I have tried several supposed ‘informed people’ but I seem to be getting different responses to my questions.

These are very good questions and made me think for a while! The answers to your questions depend on exactly what type of ADSL ‘modem’ you have installed. Most ADSL modems which come included with broadband connections are like a normal modem, they are simply a communication device which the computer controls and dials. However, there are also ADSL modem/routers. The main difference between the ADSL modem/router and a normal ADSL modem is the router allows multiple computers to be connected to the router and shares the connection between these machines. Because the connection is shared, it would be impractical (and inconvenient) for each connected computer to have a dialling program installed. If this was the case, for example, each computer in an office network which uses the ADSL connection would need a dialling program. To alleviate this problem, the ADSL modem/router acts like a separate computer and dials the connection itself. All the connection information (e.g. username, password, network addresses) is stored within the modem/router and whenever a computer needs to access the internet, the ADSL modem/router establishes the connection. Then, when no computer has used the connection for a specified amount of time (e.g. 1 hour) the connection is brought-down.

Since you mentioned ‘is it enough to exit the little ADSL icon on the taskbar’ I assume you have a standard ADSL modem, which requires you to manually establish the connection, rather than the modem automatically connecting when needed. The sure-fire way to test this theory is open your web browser and try to open a website without doing anything to connect to the internet. If a web page doesn’t appear, you’re not connected! Likewise, you can probably look at the lights on your ADSL modem to see whether a connection is active and whether any traffic is flowing over the link.

So in response to your questions, assuming you have a normal ADSL modem that requires the user to manually establish the connection, you don’t need to turn off the modem when the computer is turned off. I would actually recommend against this, since each time you turn on the ADSL modem it must re-establish certain communication protocols (such as line sync) and I don’t know the long-term effects of doing this each day. Secondly, if you have not established the ADSL connection, then your ADSL modem will not be connected and thus will not connect to the internet. Finally, it is enough to quit the little ADSL icon in the task bar.