Which of the following is a characteristic of VPNs using TLS?

The characteristic of VPNs using TLS is that they implement TLS (Transport Layer Security) and user PKI (Public Key Infrastructure). TLS is a protocol that provides a secure channel over a network by encrypting the data transmitted between the client and server, ensuring confidentiality, integrity, and authenticity. In the context of VPNs, using TLS allows for secure remote access to networks while protecting sensitive information from eavesdropping or tampering.

The inclusion of user PKI further strengthens security by allowing for the use of digital certificates for authentication. Users can be verified based on the credentials associated with their digital certificates, enhancing trust in the identity of users accessing the VPN.

Other choices do not accurately reflect the key characteristics of TLS-based VPNs. For instance, requiring the installation of native applications is not a defining aspect of TLS VPNs, as many can operate in a browser environment without the need for additional installs. Similarly, while some VPNs may operate over HTTP, commonly using port 443 for SSL/TLS, they do not specifically communicate over TCP port 80, as that is associated with unencrypted web traffic (HTTP). Finally, TLS-based VPNs do not need dedicated physical lines; they can traverse existing internet infrastructure, making them more flexible and