I want to set up a wireless internet network in my home. There are 3 laptops used by different people and I'd like if we can all use the same network, hopwever, i use my internet to pay bills, do all my banking online, and sometimes make credit card payments. Is there a very safe firewall or something that can be installed to ensure that it will be just as secure as a wired connection, even from the other people in the house?