Netgear GS724Tv4 vlan routing

Have you actualy called your ISP tech support and asked them this?  Because very few ISPs out there run gear that lacks the capability of going into bridged mode.  Keep in mind that MANY isp's call it something other than bridged mode.  For example Comcast doesen't call it anything at all, the term "bridged" exists nowhere in their modem interface.  However if you simply turn off the firewall on the modem - all the sudden you are in bridged mode and your router pulls via DHCP from their public numbers not from their modem's DHCP server.  And this is on their RESIDENTIAL service that also has telephone and TV.

Call your ISP and tell them "I have a VPN router that REQUIRES a public IP number on it's outside interface, it DOES NOT need to be a static IP number it can be dynamic, but it MUST be public with NO firewalling" and see what they say.  I am sure they have thousands of customers who are like this and their support department has heard this question a million times.

With a REAL router it's possible to have MULTIPLE privately numbered networks behind the router.  In fact that's precisely what I am posting from - a private network that is ROUTED not translated, behind another private network.

In fact, (just to dangle a carrot in front of you) I have a business customer that has THREE privately numbered networks all behind a router.  The router is the free Untangle firewall it connects the Internet to the main net, and the routers that are between the main net and the remote nets are Netgear WNDR4000s that have been re-flashed with dd-wrt.  dd-wrt allows you to turn off address translation and and turn the device into a real router in fact you can run OSPF and be right up there with the big boys.  And dd-wrt also has the ultra-special go-fast code that does fast switching in some of Netgears higher end routers like the 7000 so you can route at gigabit speeds.

There's a whole world of routing out there beyond 'the book' I encourage you to investigate.