L2TP

Layer 2 Tunneling Protocol (L2TP) is a tunneling protocol used to support virtual private networks (VPNs) or as part of the delivery of services by ISPs. Developed as an enhancement of the Point-to-Point Tunneling Protocol (PPTP) and Layer 2 Forwarding (L2F), L2TP provides encryption, authentication, and compression functionalities, enabling secure data exchange across public networks like the Internet.

L2TP was jointly developed by Microsoft and Cisco and was introduced in 1999. The protocol combines the best features of PPTP from Microsoft and L2F from Cisco. L2TP operates at the data link layer (Layer 2) of the OSI model, enabling it to encapsulate traffic of any network layer protocol. One notable aspect of L2TP is that it relies on an encryption protocol, such as IPsec, to ensure data security as it lacks intrinsic encryption features. By doing so, it provides robust protection while keeping the tunneling functionalities efficient and flexible. Commonly used in VPNs, L2TP helps businesses connect remote users securely to corporate networks, ensuring confidentiality and integrity of transmitted data.