I need some quick topic Underlay, Overlay and GET VPN

Security ASA
1

Hi Rene,

Can you please help me to understand three topics. I need to implement something related to these three in my company.

  1. What is underlay?
  2. What is overlay?
  3. and GET VPN

I need to implement one GET VPN Client in MPLS VPN network.

Regards,
Manami

2

Hi Manami,

An overlay network is usually a virtual network that runs of top of an underlying network, the underlay.

For example, look at DMVPN:

The DMVPN tunnels are the overlay network, the underlay is the network with the Internet connections.

GET VPN is still on my list to create a lesson for, it’s a bit too detailed to explain in a few words here.

3

Hi Rene,

Can I have an example of Overlay Network? Why do we need a virtual network that runs of top of an underlying network like DMVPN?

Regards,
Manami

4

Hi Manami,

DMVPN is the overlay (the virtual network), the underlying network is the infrastructure you use for perhaps Internet connectivity.

Rene

5

I understand.

Thank you.
Manami