Which VPN protocol uses UDP port 1701 and does not provide confidentiality and authentication? Dominik February 22, 2020 Anonymity Layer Two Tunneling Protocol (L2TP), itself an augmentation of the Point-to-Point Tunneling Protocol (PPTP), is a VPN protocol that leverages User Datagram Protocol (UDP) port 1701. Unfortunately, it does not provide any confidentiality nor meaningful identity authentication. The reason why you would still want to send some [emphasis on some] data over this or any other UDP port over one belonging to a Transmission Control Protocol (TCP) is that the latter can be such a bad fit for certain scenarios that critical failures stemming thereof are a full-fledged phenomenon with a powerful name – “TCL meltdowns.” Back to the point, L2TP has been in use for almost the entirety of this century, having evolved not just into a useful support protocol for VPNs, but also into a frequently encountered component of ISP infrastructure. While it ensures neither user authentication nor user confidentiality, the lack of both ironically makes it not a complete privacy disaster. Similar questions to “Which vpn protocol uses UDP port 1701 and does not provide confidentiality and authentication?”: We also answered these questions, do check them out: What dedicated hardware device aggregates hundreds or thousands of vpn connections? Which process is used to protect transmitted data in a VPN? Before ipsec can be used as a virtual private network (VPN) service, what must be created? When employees have multiple concurrent connections, what might be happening to the VPN system? What does a VPN use to ensure that any transmissions that are intercepted will be indecipherable? Which VPN protocol works at Layer 3 and can encrypt the entire TCP/IP packet?