What is IPsec NAT Traversal

 What is IPsec NAT Traversal? How to configure IPsec NAT Traversal?

IPsec NAT traversal (NAT-T), also known as UDP encapsulation, NAT-T is a technique that allows traffic to get to a specific destination when a device does not have a public IP address. NAT-T makes sure that the IPsec VPN connection is open when traffic is going through the gateways. This usually happens when your ISP is doing NAT, or when the external interface of your firewall is connected to a device that has NAT enabled.


NAT Traversal (NAT-T) adds a UDP header and a special payload to the IPsec packet, which makes it look like a normal UDP packet to the NAT device, and the NAT device will make the required changes and process the message.