The acronym L2TP stands for Layer 2 Tunneling Protocol, and is a series of rules that allow internet service providers to allow for VPNs. L2TP on its own, though, does not encrypt data, so does not provide complete privacy for users. That’s why L2TP is usually used with IPsec to help protect the online privacy of users.
IPsec is a series of protocols, or rules, that virtual private networks use to secure a private connection between two points, usually a device such as a laptop or smartphone and the Internet. Without these protocols, VPNs would not be able to encrypt data and ensure the data privacy of users. The name IPsec stands for Internet Protocol Security.