Virtual Private Network (VPN)
A Virtual Private Network (VPN) creates an encrypted tunnel between a device and a remote network or server, protecting data in transit and allowing the device to appear as if it is connected from a different network location.
Definition
A Virtual Private Network (VPN) creates an encrypted tunnel between a device and a remote network or server, protecting data in transit and allowing the device to appear as if it is connected from a different network location.
Overview
A VPN works by encrypting all traffic leaving a device and routing it through a secure tunnel to a VPN server, which then forwards the traffic to its destination on the user's behalf. Because the traffic is encrypted, anyone intercepting it — on a coffee-shop Wi-Fi network, for example — sees only unreadable ciphertext rather than the actual data being sent, protecting against eavesdropping in ways similar to how TLS protects individual web connections. VPNs serve two broad purposes. Remote-access VPNs let individual employees securely connect to a corporate network from home or while traveling, as though they were plugged in at the office, historically the dominant model for securing remote work before the rise of Zero Trust access architectures that verify every request individually rather than trusting anyone "inside" the VPN tunnel. Site-to-site VPNs instead connect two entire networks — for example, linking a branch office to company headquarters, or connecting an on-premises data center to a cloud provider — over the public internet as if they were on the same private network. Common VPN protocols include IPsec, OpenVPN, and the newer WireGuard, which offers stronger performance and a simpler codebase than older protocols. Consumer VPN services also use this same underlying technology to route a user's traffic through a third-party server, primarily for privacy and to mask the user's originating IP address and geographic location. While VPNs remain widely used, security practitioners increasingly note their limitation: once connected, a VPN user typically has broad network access, which conflicts with the least-privilege principle at the heart of Zero Trust. As a result, many organizations are supplementing or replacing traditional VPN access with more granular, per-application Zero Trust Network Access (ZTNA) solutions.
Key Concepts
- Encrypts all traffic through a secure tunnel between device and server
- Remote-access VPNs connect individual users to a corporate network
- Site-to-site VPNs connect two entire networks over the public internet
- Common protocols include IPsec, OpenVPN, and WireGuard
- Masks the user's originating IP address and location
- Historically the dominant model for securing remote work access
- Increasingly complemented or replaced by Zero Trust Network Access (ZTNA)
Use Cases
Frequently Asked Questions
From the Blog
Network Topology Explained: Star, Bus, Ring, and Mesh
Network topology is the physical or logical arrangement of devices and connections in a network, and it determines a network's speed, cost, and fault tolerance. This guide compares star, bus, ring, mesh, and hybrid topologies with real trade-offs.
Read More Cloud & CybersecurityWhat Is a Virtual Machine (VM) and How Does It Work?
A virtual machine (VM) is a software-based emulation of a physical computer that runs its own operating system and applications on top of shared hardware, kept isolated from other VMs on the same host.
Read More Cloud & CybersecurityThe Network Layer Explained: How Data Finds Its Way
The network layer is the part of a computer network that decides how data packets travel from a source to a destination across interconnected networks. This guide explains its job, the protocols it relies on, and why routing and addressing sit at its core.
Read More Cloud & CybersecurityNetwork Engineer Interview Questions and How to Answer
Network engineer interviews test your grasp of core concepts like the OSI model, subnetting, routing protocols, and troubleshooting method. This guide walks through the most common questions and what a strong answer actually sounds like.
Read More