Dynamic routing over wan links.

How do I enable routing protocols across WAN links in this scenario? Like having an office in New York and a branch office in London? Will it work or is it better to implement IPsec VPN and how does the VPN work when both public IP addresses are not on the same subnet? The problem I'm thinking of is how will the routing work when the addresses given by ISP are not on the same subnet or the offices have different ISPs. All these work well in my Lab because the routers are always on the same subnet. Can anyone who has the experience or has implemented this or who knows the best way to go about this please explain?
Thanks!!!

Routing Across Wan.JPG

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Comments

billscott92787

What type of setup do you have between these two sites? Is it a frame-relay connection? What exactly is running to connect the two?

My guess so far based on the diagram is the best results is going to be an IPSEC Site-to-Site VPN connection. But I'll wait to see what your response is

peanutnoggin

+1 on the site to site vpn. The site-to-site vpn would allow you to send the routing updates over the vpn connection between the sites.

ColbyG

To run a routing protocol, GRE tunnels.

peanutnoggin

ColbyG wrote: »

To run a routing protocol, GRE tunnels.

ColbyG,

That was one of my first thoughts... but something was telling me that GRE tunnels are unsecured... is that true? I can't remember!

-Peanut

networker050184

Correct, GRE is not encrypted, but you can do IPSEC over GRE.

mathelize

billscott92787 wrote: »

What type of setup do you have between these two sites? Is it a frame-relay connection? What exactly is running to connect the two?

My guess so far based on the diagram is the best results is going to be an IPSEC Site-to-Site VPN connection. But I'll wait to see what your response is

Nothing in between, just normal internet connections between the sites. Is it possible to run routing protocols over normal ADSL and cable broadband? How would it work when the public IP addresses are on different subnets. A sample configuration would be very appreciated.

mathelize

With some of the suggestions I've seen now. So it's possible to use VPN to link your networks that span various geographical locations together and then implement dynamic routing protocols to update routes. Correct me if I'm wrong please.

Cyanic

That sounds about right to me.

burbankmarc

These links might help you, but they are GRE over IPSec.

Configuring a GRE Tunnel over IPsec with OSPF - Cisco Systems

https://www9.cisco.com/en/US/tech/tk583/tk372/technologies_configuration_example09186a008019d6f7.shtml