Changes

It should also be noted the connection type used is '''Tunnel''' and not '''Transport'''. Tunnel protects the internal routing information by encrypting the IP header of the original packet. The original packet is encapsulated by a another set of IP headers. Transport encrypts only the payload and Encapsulating Security Payload (ESP) trailer; so the IP header of the original packet is not encrypted. Transport mode is usually used when another tunneling protocol (such as [[VPN#GRE_Tunnel|GRE]], [[VPN#L2TP|L2TP]]) is used to first encapsulate the IP data packet, then IPsec is used to protect the GRE/L2TP tunnel packets.

It should also be noted the connection type used is '''Tunnel''' and not '''Transport'''. Tunnel protects the internal routing information by encrypting the IP header of the original packet. The original packet is encapsulated by a another set of IP headers. Transport encrypts only the payload and Encapsulating Security Payload (ESP) trailer; so the IP header of the original packet is not encrypted. Transport mode is usually used when another tunneling protocol (such as [[VPN#GRE_Tunnel|GRE]], [[VPN#L2TP|L2TP]]) is used to first encapsulate the IP data packet, then IPsec is used to protect the GRE/L2TP tunnel packets.

Tunnel is more widely implemented in site-to-site VPN scenarios and supports NAT traversal, that's why we chose it for the example.

Tunnel is more widely implemented in site-to-site VPN scenarios and supports NAT traversal. For instructions on how to configure Transport mode, you may want to check out our '''[[L2TP over IPsec]]''' article.

==Router configuration==

==Router configuration==