What characteristic describes a VPN?

A VPN, or Virtual Private Network, is characterized by its ability to establish a secure and encrypted connection over a less secure network, typically the internet. This is accomplished through tunneling protocols that encapsulate the data being sent, ensuring that it is protected from eavesdropping or interception. Secure remote access is a primary function of VPNs, allowing users to connect securely to a private network from a remote location, which is essential for businesses that require remote work capabilities.

The mention of tunneling in the correct answer highlights this key feature, as tunneling protocols like PPTP, L2TP, and OpenVPN are utilized to create these secure communication channels. The security aspects of a VPN are crucial, especially in today's environment where data protection and secure communications are paramount.

The other options reflect different networking concepts that do not appropriately define what a VPN is or does. A VPN is not just a network that provides public internet access, nor is it a protocol focused solely on packet switching. Furthermore, it does not relate to local area network technologies, which typically involve connections within a limited geographic area rather than secure connections over the internet. Thus, the unique characteristic of a VPN lies in its secure tunneling capabilities for remote access.