Question : W2K3 Server NAT/Router and VoIP configuration

Hello people.. this is my question:

My setup looks like this:
                      Internet        201.220.ef.gh/192.168.5.1                          
                      VoIP            10.107.5.128/255.255.255.128                                    10.107.5.130
Internet/--->Cisco2500-----> 2K3Server RRAS/NAT---------> Wireless Router ---->Sip phone.
  VoIP        201.220.ab.cd                                    !            *supports Routing,
                                                                       PC             IP forwarding,
                                                                    Network        Firewall and
                                                                                        everything else*

I used to have this:
                                                        VoIP
                                        _________________________       2 IPs
Internet/ ------>Cisco2500 /                                            \  Wireless Router----> Sipura
  VoIP                               \-----2K3 Server RRAS/NAT ---/ \
                                                                    Internet        PC Network

Hope the diagram makes sense.. I have to change this because we got a Bandwidth controller box and it does not find the VoIp network if it's on a sepparate interface from server(I guess). so....
 How can I make my server pass the VoIP to the internal network to Sipura devices and still have NAT working for internet to work on computers and Vonage lines, I CANNOT make nat on Sip packets my provider created these networks and I cannot change them(they told me that the softswitch would deny my connection if it's from my Public IP from server)... Please help me!!.
I'm staying up at nigth trying to find a solution but no luck, found what I thought would work with IPSec, but seems to be more specific for server-to-server thing going on there.. again!, please help!.

Answer : W2K3 Server NAT/Router and VoIP configuration

" I really want to Windows to work like my Cisco..."

That is basically a mistake to expect that.  Windows is a FILE and APP sharing server, it does NOT make a reliable PORT server like a router.  Windows cannot even compete for stability with a cheapo router, let alone a top quality Cisco designed for the purpose.  Windows never works as well as a dedicated router.

Sure you can fiddle with windows until it works for one setup, but then you make changes and something else breaks, then it loses its TCP/IP stack because of internal software problems, so you have to rebuild the stack, and then everything is blown away, you have to do it all again.  It is not LONG-TERM dependable for routing.

Redesign the network to where ALL routing functions are done by Cisco routers with the right capabilities.  Leave windows to what it does best, file and app serving.  Its the only way to get long term stability,.