I have an ADSL2+ broadband connection via Telecom feeding a D-Link modem/router and then several computers around the house accessing this service via ethernet cable or wireless.


I conduct financial instrument trading from home, so a reliable connection is critical. Before Xmas I bought a Telecom broadband USB modem to contect to their cellphone network.


How do I set my computer (ie just my computer - not all the household) up so that if I lose my LAN connection and/or the ADSL feed the USB modem will automatically connect to Telecom's cellphone network. This needs to be done in a manner that means the USB modem is not using any data when not activated.