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OSPF virtual link thru an IPSEC VPN

Here is my understanding...

Because IPsec does not support Multicast we cannot run a routing protocol through an IPsec VPN. So we use GRE tunneling.

If GRE is unavailable because of the device, is there another way?

My one thought is...

I understand that a virtual link creates a "tunnel".

Can I create a virtual link thru an IPsec VPN tunnel?

What protocol does the "Virtual Link Tunnel" use that would allow it to or not too be created?


Re: OSPF virtual link thru an IPSEC VPN

The concept of virtual links and VPN tunnel is entirely different, OSPF virtual link is not used as a substitute for any routing protocol. It is used to connect to the backbone area(in OSPF) through a nonbackbone area. The information about OSPF virtual links can be obtained from the following documenst.

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Re: OSPF virtual link thru an IPSEC VPN

Thank you very much.

I am familiar with virtual links and VPN tunnels. I understand the main purposes and functionality of the two and have deployed them both.

I have a problem and am exploring pushing some technology beyond its normal use to solve that problem.

IPsec does not support Multicast so OSPF will not cross a VPN WAN without a little help.

Do you know if IPsec supports putting a virtual link through it?

(So the routing protocol will go through the VPN tunnel encapsulated in another protocol)

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