My office laptop has a VPN client installed. At home, I start this client, choose one host out of given many hosts and connect using an RSA token. From this point onwards, my browser is able to access all the office sites, as if I was in office and I can ssh to my office machines.
I am trying to get some basic understanding of how this thing works. I have heard of keywords like tunelling, but not sure how and where these are coming into picture.
(1) After getting on VPN, does my IP address change? or is it still same as what is provided by by ISP?
(2) Fine, even when I start a vpn client software, how does it tell firefox to do things any differently such that it allows me to access office intra sites? i.e. how does this client change settings used by firefox...?