Overlay

An overlay network is the virtual network, such as an IPsec connection, that rides on top of the underlay.

In the following example, IPsec VPN connects each underlay interface to the hub:

• Branch_WAN1 connects to HUB_WAN1
• Branch_WAN2 connects to HUB_WAN2

These will be referred to as WAN1_VPN and WAN2_VPN respectively.