Obfuscation
Disguising VPN traffic so it resembles ordinary encrypted web traffic to a system inspecting the connection.
Glossary
Deep packet inspection
Also called: DPI
Network equipment that examines the structure of traffic rather than only its destination address.
Why it matters
It is what separates a network that blocks a list of sites from one that detects and blocks the tool you use to reach them.
What most explanations leave out
DPI cannot read the contents of properly encrypted traffic. What it reads is shape: packet sizes, timing, handshake structure. That is why obfuscation works by changing the shape rather than by adding encryption on top.
Related terms
SNI
The field in a TLS handshake that names the site being requested, historically sent unencrypted even over HTTPS.
Terms are defined here because they appear in our scoring rubric or in provider reviews, not to fill a glossary.