SoftEther VPN and L2TP
Layer Two Tunneling Protocol (L2TP) uses TCP port 1701 and is an extension of the Point-to-Point Tunneling Protocol. L2TP is often used with IPSec to establish a Virtual Private Network (VPN). Point-to-Point Tunneling Protocol (PPTP) uses TCP port 1723 and IP port 47 Generic Routing Encapsulation (GRE).