How Meet encrypts information
To keep your information secure, Hangouts Meet video meetings are encrypted in transit. The encryption occurs with video meetings on a web browser, on the Hangouts Meet Android and Apple® iOS® apps, and in meeting rooms with Google meeting room hardware.
How audio and video is encrypted
Audio and video is encrypted using SRTP_AES_CM_128_HMAC_SHA1_80 (128-bit AES encryption and SHA-1 HMAC for authentication). If you join a video meeting by phone, the audio follows the telephone carriers' network and might not be encrypted.
To improve audio and video quality, Meet video meetings might use a direct peer-to-peer connection. Routing through a direct peer-to-peer connection can sometimes be more efficient than using Google's servers.