Despite claiming to offer end-to-end encryption, Zoom is using its own definition of the term, one that lets Zoom itself access unencrypted video and audio from meetings.
Instead it offers what is usually called transport encryption.
A Zoom spokesperson wrote, “Currently, it is not possible to enable E2E encryption for Zoom video meetings. Zoom video meetings use a combination of TCP and UDP. TCP connections are made using TLS and UDP connections are encrypted with AES using a key negotiated over a TLS connection.”
The encryption that Zoom uses to protect meetings is TLS, the same technology that web servers use to secure HTTPS websites.