Innovation Behind Webex Mute
Providing the Best User Experience while Protecting Privacy
Providing clear audio that is free of background noise is critical to any real time communications – especially when it comes to video conferencing. At Webex, our goal is to always provide high quality audio for anyone who joins Webex meetings, from any device. We’ve innovated to solve many common problems in video meetings in order to provide this high quality audio experience. Webex Mute
In January 2022, the author of a research paper, who reported that his research team was investigating privacy in video conferencing applications, contacted the Webex team. The research paper was aimed at investigating the behavior of the mute button in various video conferencing applications. This blog provides details on the paper and behavior of Webex while on mute.
The “You are on Webex mute!” problem
One of the most common problems we’ve seen is when meeting participants inadvertently speak while they are on mute. In some cases — if what they say is short — others in the meeting may not even realize that someone was speaking. In other cases, the speaker must repeat what was said. Having to repeat what was said is not only an incredible waste of time for all participants in the meeting, but it can also make the meeting less inclusive.
To help improve this, we added a feature to Webex that notifies the user if they are speaking while are on mute.
This feature was released in the November 2020 version of Webex (40.11).
To build this feature, Webex had to sample the microphone while the user is muted. The audio sampled was analyzed on the user’s computer. Audio samples were never sent to Webex cloud.
Webex collects telemetry as the product is used to better understand the quality of experience we are providing for the end user. This telemetry is used to provide administrators help in troubleshooting meetings and for analytics.
As part of our efforts to provide clear consistent audio, Webex submits telemetry data which shows the audio energy levels (among other metrics) captured from the microphone. At the time of the researcher’s findings, Webex submitted audio gain related metrics (min, max, and mean gain), even when the user was on mute. Measuring audio gain is important, as it helps the “auto adjust microphone level” feature, providing all users with consistent volume levels in a meeting – i.e., no one sounds too loud or too quiet.
Once our team was notified by the researcher that Webex was collecting telemetry data even when muted, we reviewed our use of this telemetry data when a user is on mute. We concluded that eliminating this data will address the concerns raised by the researchers, while at the same time not significantly impact troubleshooting or analytics capability. As a result of our review, we eliminated collecting telemetry data when users are on mute—by zeroing those values—in the January release of Webex.
We are thankful to the researchers for sharing their findings with us. We want to reiterate:
- Webex never sends audio to the Webex cloud while a user is on mute.
- Webex telemetry was always sent to the Webex cloud over secure and encrypted (HTTPS) connection.
- It was never possible for a third party to access this telemetry by inspecting network traffic.
- The researchers retrieved clear text data by attaching a debugger to the Webex process, which requires access to the user’s computer.
- As stated in our Webex Privacy Data Sheet, Webex does not monitor or interfere with your meeting traffic or content.
Our commitment to privacy and transparency
As a Cisco product, Webex uses the Cisco Security and Trust Organization to manage security. Webex leverages groundbreaking innovations and approaches to develop world-class collaboration solutions that are built-in, offering users a frictionless experience while protecting their content.
We believe that being transparent is important in building trust. Webex and Cisco are committed to user’s privacy. Our privacy data sheets and privacy data flows are available for download by anyone.
We hope this blog helps users better understand our commitment to providing the best user experience possible while at the same time protecting privacy.
Jun 1, 2023 — Geoffrey Huang