I'm sorry but I'm having issues with the forum maybe its because I'm using Firefox 4 beta 7 since the browser already crashed several times when posting, Ill repost from another browser:
I came across this network and I’m interested to know how the VPN is functioning, I googled a lot a couldn’t find an answer so I would really appreciate your feedback:
Well I have 3 sites the HQ router (Cisco 1841 Integrated Services Router) is connected to two branch routers (Cisco 871 Integrated Services Router) through VPN in which VoIP and Data access is provided by the HQ to the other sites.
What is baffling me is that both of the branch sites have regular SOHO ADSL with a non public IP assigned by the ISP that is NAT is implemented and no static IPs are assigned to the branch routers or DSL modems .
My question is how can site-to-site VPN operate with only one Public static IP being in-use?
Or are the connected routers, actually acting as VPN clients, in this case how this is possible? That is can a router connect to another router, the same way a mobile user connects through the Cisco VPN Client software.
PS: the HQ is an IT services company that provided the VPN service to the 2 sites (A small business) I will need to replicate the scenario since the 2 sites no longer want to use a third party for the service and are not expecting to get real IPs since the prior solution was working fine with the only real IP being assigned to the HQ router, the third site would be eliminated so the new topology would be point-to-point.
