How it works
A VPN client wraps each packet in an encrypted envelope and sends it to a VPN server, which unwraps it and passes it on. Others on the same café Wi-Fi, and the internet provider, see only scrambled traffic heading to that server. Common protocols are WireGuard (small, fast and built into Linux), IPsec (built into most business routers and firewalls) and OpenVPN (older and flexible, over TCP or UDP).
VPNs come in a few shapes. Site-to-site VPNs join office networks over the internet. Remote-access VPNs let staff reach internal systems from home. Consumer VPN services route browsing through their own servers to hide it from the local network or to appear in another country. Mesh VPNs such as Tailscale (built on WireGuard) connect devices directly to each other where they can, so there is no central VPN server to run.
A VPN moves trust rather than removing it: the VPN provider can now see what the local network used to see. It does not make anyone anonymous to websites, which still recognise logins and cookies, and it adds delay, most of all when traffic detours through a distant server. Zero trust access tools, which check each app login separately, are a common alternative to one office-wide VPN.
VPN pros and cons
Pros
- Encrypts traffic on untrusted networks such as public Wi-Fi
- Gives remote staff safe access to internal systems
- Joins offices and cloud networks as if they were one network
- WireGuard and OpenVPN are free and open source
Cons
- Adds delay, and speed depends on the VPN server's load and distance
- The VPN provider sees the traffic instead, so it has to be trusted
- No anonymity from websites, which still see logins and cookies
- One stolen VPN login can open up a whole internal network
When to use VPN
Pick it when
- Staff need to reach internal servers or tools from outside the office
- Linking two offices, or an office and a cloud network
- Working on public Wi-Fi you do not trust
- Reaching home or lab machines from anywhere (a mesh VPN fits well)
Skip it when
- The goal is anonymity, which a VPN does not provide
- Everything already runs over HTTPS and nothing internal needs reaching
- Low delay matters, as in games or video calls, and the nearest VPN server is far away
VPN pricing
Free tier
WireGuard and OpenVPN are free to run yourself. Tailscale is free for personal use (up to 6 users) and about $8 per user a month for businesses. Proton VPN has a free plan; Mullvad costs a flat €5 a month.
VPN pricing page (opens in a new tab)Approximate, checked September 2026.What the other tools cost
VPN vs the alternatives
Related terms
More in Networking
Getting around