VPN Glossary (2026): Plain-English Definitions of Essential VPN Terms

A VPN is a tool that encrypts your connection and changes your virtual location. Under the hood, the same building blocks power every use case: safer Wi-Fi, remote work, streaming stability, and troubleshooting.

VPN jargon can feel like a secret club: WireGuard, DNS leak, kill switch, RAM-only servers, obfuscation… This glossary translates the terms into human language, plus quick “why it matters” context so you can actually use the info.

How to use this VPN glossary

This page is organized into clusters you’ll actually run into when picking a VPN, setting it up, or fixing a problem:

• Core concepts (exit IP, latency, throughput)
• Protocols + encryption (WireGuard vs OpenVPN, AES-256 vs ChaCha20)
• Leak protection (DNS leaks, IPv6 leaks, WebRTC leaks)
• Privacy + trust (no-logs, audits, RAM-only servers, jurisdiction)
• Performance (throttling, congestion, routing)

VPN Term Finder (interactive)

Core VPN concepts

VPN (Virtual Private Network)

An encrypted tunnel between your device and a remote server. It hides your real IP from the websites you visit and protects traffic from local snooping (public Wi-Fi, some ISP monitoring, etc.).

VPN client / VPN app

The app you install. It controls protocol choice, encryption settings, kill switch behavior, DNS handling, and server selection.

VPN server / Exit server

The VPN provider’s server that your traffic exits from to the public internet. Websites see this server’s IP, not your home or mobile IP.

Exit IP / VPN IP

The public IP address assigned by the VPN server. This is what streaming platforms and websites use for geo-checks and fraud checks.

Latency / Ping

How long a packet takes to travel between your device and a server (ms). Lower ping matters for gaming, calls, and “snappy” streaming.

Throughput / Bandwidth

How much data per second goes through the tunnel (Mbps/Gbps). Throughput is your “how fast can it go?” number; latency is your “how quickly does it respond?” number.

Protocols & encryption terms

Encryption

The scrambling process that makes your traffic unreadable to outsiders during transit. Encryption is the “lock”; the protocol is the “delivery system”.

AES-256

A widely used encryption standard. When implemented correctly, it’s extremely strong.

ChaCha20-Poly1305

A modern cipher suite that performs very well on mobile devices. Many WireGuard implementations use it by default.

VPN protocol

The rules for how your device connects and maintains the encrypted tunnel.

WireGuard

A modern protocol designed to be fast and stable with a smaller codebase.

OpenVPN

An older, battle-tested protocol. It can be very reliable, but it may run slower than WireGuard, especially on phones or weaker routers.

IKEv2/IPSec

A good mobile-friendly choice when you move between Wi-Fi and 5G. It can reconnect quickly.

Leak terms: DNS, IPv6, WebRTC

Leak test

A check that verifies whether your real IP, DNS, or browser network signals are exposed while the VPN is on.

DNS leak

When your browser/device keeps using your ISP DNS instead of the VPN DNS. Even with encrypted traffic, DNS leaks can reveal which domains you’re visiting.

IPv6 leak

When IPv6 traffic bypasses the VPN tunnel. This is one of the most common “why does the site still know my location?” issues.

WebRTC leak

A browser feature for real-time communication that can sometimes reveal network details.

How terms work together

Privacy, logs & trust terms

No-logs policy

A promise that the provider does not store identifiable activity logs (sites you visit) or connection logs tied to you. The best providers back claims with audits.

Independent audit

A third-party security review. Audits can cover logging, apps, server configuration, and infrastructure controls.

RAM-only servers

Servers that run without persistent disks, so data is wiped on reboot. It’s not magic, but it reduces the chance of data lingering.

Jurisdiction

The legal environment where the company is registered and operates. It can influence data request processes.

Streaming & performance terms

ISP throttling

When an ISP slows certain traffic types (often video) during congestion. A VPN can make traffic harder to classify, but routing still matters.

Congestion

Overloaded servers or routes. Switching to a less congested nearby location often fixes buffering quickly.

Obfuscation / Stealth

Techniques that disguise VPN traffic to look like normal HTTPS. Useful when networks block VPNs (workplaces, hotels, restrictive regions).

Technology updates for 2026

Post-Quantum Cryptography (PQC)

PQC refers to encryption algorithms designed to remain secure even against future quantum computers. In VPN context, this most often shows up as quantum-resistant key exchange experiments. Today, treat PQC as a bonus: everyday safety still depends far more on leak protection, kill switch behavior, audits, and stable server infrastructure.

Example A practical “PQC-style” deployment is when a VPN adds an extra quantum-resistant step to the handshake so that even if someone records encrypted traffic now, it’s harder to decrypt later.

Manifest V3 & VPN (browser privacy changes)

Manifest V3 is a Chrome extension platform change that can reduce the capabilities of some older content blockers. A VPN does not replace an ad blocker, but it can help with privacy in a different way: protecting traffic on untrusted networks and, in some setups, using DNS-level filtering (where available) to block known trackers or malicious domains before the browser loads them.

Example If an extension becomes weaker, DNS-level blocking can still stop some tracking domains from resolving. That said, it won’t block everything a full browser extension can.

VCN (Virtual Cloud Network) integration

VCN (Virtual Cloud Network) describes private networking in cloud platforms (subnets, routing tables, gateways, security rules). A consumer VPN is usually device ↔ VPN server, while a VCN is your organization’s private cloud network. For remote work, they often meet: users connect via VPN, then access private cloud resources through routing controls.

Example A remote employee uses a VPN tunnel to authenticate into a company gateway, then reaches internal cloud subnets that are not exposed to the public internet.

Privacy red flags (anti-glossary)

• “Proprietary encryption” — closed, undocumented crypto is hard to verify and easy to get wrong.
• “Virtual locations” — the server may physically be far away while showing a different country IP, increasing latency and instability.
• “Lifetime subscription” — often a sign of unsustainable infrastructure or overloaded servers; quality networks cost money every month.
• “No logs” with zero audits — could be true, but you’re relying on marketing rather than evidence.
• “Free, unlimited, no ads” — if there’s no clear business model, ask what’s being monetized.

Technical checklist (2026)

If you want a quick “am I doing this right?” list, save this section and revisit it when you switch providers or devices:

• [ ] Protocol: WireGuard (or a WireGuard-based option)
• [ ] Encryption: AES-256 or ChaCha20
• [ ] Leak protection: DNS + IPv6 protection enabled
• [ ] Kill switch: enabled (system-level if available)
• [ ] Trust: independent audits or clear technical documentation
• [ ] Reality check: run a leak test after setup, and after major OS/browser updates

Not sure about a term?

FAQ

What are the three most important VPN terms to know?

If you’re in a hurry: kill switch, DNS/IPv6 leak protection, and WireGuard.

Why do I get captchas with a VPN?

Shared IPs. Many users exit from the same IP, which triggers anti-bot systems. A dedicated IP can reduce captchas, but it can also reduce anonymity.

Why does a VPN drain phone battery?

Some protocols are heavier on CPU, and constant reconnection (poor signal) is a battery killer. WireGuard is usually efficient; IKEv2 can reconnect quickly when switching networks.