VPNs, Tor and proxies: who you shift trust to

The earlier lessons showed that your ISP, the Wi-Fi owner and the DNS resolver can all see which sites you visit, even over HTTPS. VPNs, Tor and proxies are three different ways of routing your traffic through another party first, so that party — not your ISP or the site — sees your real IP address. Each does this differently, and each moves your trust to a different place rather than removing the need for trust altogether.

A forward proxy: a middleman, not an escort

The simplest option is a forward proxy: a server that receives your requests and passes them on to the destination on your behalf, so the destination only ever sees the proxy’s address. Cloudflare’s Learning Center lists common reasons people use one, including getting around a network’s content filtering, and making it harder to trace a post on a website back to the person who wrote it. A basic proxy typically only handles the connection you point at it, and unless it is combined with its own encryption, everything it forwards can still be read by the proxy operator and by anyone watching between the proxy and the destination.

VPNs: one tunnel, one company you must trust completely

A VPN wraps all of your device’s traffic in an encrypted tunnel to a server run by the VPN provider, which then forwards it onward. The Electronic Frontier Foundation’s Surveillance Self-Defense guide explains the effect plainly: your traffic “appears to originate from the VPN itself, rather than your internet service provider”, so your ISP and the websites you visit see the VPN’s address instead of yours. But the guide is equally direct about the trade-off: everything that leaves the tunnel “is all visible to the VPN provider.” Your ISP’s view of your browsing is replaced by the VPN’s view of it, including which domains you contacted, when, and roughly how much data moved. A disreputable provider could log or sell that, and any provider can be compelled by the laws of the country it operates in to hand over what it holds. EFF also cautions that a VPN mainly hides your network-level location and identity from your ISP and the destination site; it does not stop a website from tracking you through cookies, logins or fingerprinting once you are there, and today most web traffic is already encrypted by HTTPS regardless.

Tor: splitting the trust across three relays

Tor takes a different approach: instead of one server that sees both who you are and where you are going, it routes your connection through at least three volunteer-run relays in sequence, each one wrapped in its own layer of encryption. The Tor Project explains that the first relay can see your real IP address but not your destination or your activity, the middle relay sees neither, and the last relay — the exit node — sees the destination but not who you are, unless the site itself later identifies you (for example, if you log in). No single relay in the chain has both pieces of the picture at once.

The Tor Project is candid about the limits. It states directly that “it is impossible to have perfect anonymity, even with Tor.” Tor only protects traffic from applications that are actually configured to use it, so other programs on the same device can still leak your identity. It does not hide the fact that you are using Tor from someone watching your connection, only what you do over it. And if the destination site is not itself using HTTPS, the exit relay can see the unencrypted content leaving the Tor network, just as any last hop can on the ordinary internet. Signing into an account, or typing your name, undoes the anonymity regardless of how the traffic got there.

Choosing among them