L2TP VPN uses which port?

L2TP VPN uses which port?

• A. 1701
• B. 333
• C. 80
• D. 443

Answer: (A)

L2TP VPN uses UDP port 1701 because L2TP is defined to run over UDP on that port to establish the tunnel. That address is specifically assigned for the L2TP control and data signaling. In practice, L2TP is often paired with IPsec for encryption, which brings in separate ports for security (IKE on 500 and NAT-T on 4500, with ESP carrying the actual data). The other ports listed are standard web-related ports (80 for HTTP, 443 for HTTPS) or nonstandard VPN ports, so they don’t apply to the L2TP tunnel itself. So the correct port is 1701.

L2TP VPN uses UDP port 1701 because L2TP is defined to run over UDP on that port to establish the tunnel. That address is specifically assigned for the L2TP control and data signaling. In practice, L2TP is often paired with IPsec for encryption, which brings in separate ports for security (IKE on 500 and NAT-T on 4500, with ESP carrying the actual data). The other ports listed are standard web-related ports (80 for HTTP, 443 for HTTPS) or nonstandard VPN ports, so they don’t apply to the L2TP tunnel itself. So the correct port is 1701.