Why screen sharing requires our software
Your webinar room broadcasts camera and microphone through the WebRTC technology built into your browser, and for a talking head that is the right tool. Screen sharing is the one mode that asks you to install a small program of ours first.
The reason is that your screen is a different kind of content. A webcam shows your face. A shared screen can show documents, emails and open work files, and it has to stay legible rather than merely watchable. We wrote our own software to meet both of those requirements.
Who can see your screen
Everything the software sends is encrypted with TLS (Transport Layer Security), which protects your screen against interception on the way.
At the other end, only people who are in the webinar room and hold the right access rights can see it. Every screen sharing session is protected by its own unique key, so nobody outside that session can watch.
What encryption cannot do is control the people you invited. Anyone who can see your screen can also photograph or record it, exactly as they could in a meeting room. So the practical rule stays the same as it always was, which is to close anything you would not want in the recording before you start sharing.
Fewer lost packets
WebRTC runs over UDP (User Datagram Protocol), and UDP does not guarantee that every packet arrives. For a webcam a dropped packet costs you a fraction of a second of a moving face, which nobody notices. On a screen full of small text the same loss is much more visible. Our software keeps those losses to a minimum, so the picture of your screen stays stable.
Picture quality
The program is built to send a sharp image of your screen. It gets there by keeping the amount of transmitted data down and using advanced compression, which avoids delays even when the system is under load.
Quality still depends heavily on your own computer and your internet connection. However hard we work on the encoding, an old or slow machine or a weak connection produces a worse picture than you were expecting.
Browser limitations
Some browsers restrict what can be transmitted or handle certain protocols badly. Our software sits outside those restrictions, so screen sharing behaves the same way whichever browser you present from. The trade is that it needs a computer the plugin runs on, meaning Windows or macOS. On Linux the plugin does not run and screen sharing is not available, which technical requirements notes alongside the other platform limits.
Getting the software
How to share your screen during a webinar walks through the whole thing, from downloading the plugin inside the room to choosing a monitor or a single window. On macOS there is one extra step, because the app also needs permission under "Screen & System Audio Recording" in your system settings before it can share anything. The same plugin powers our alternative broadcasting technology, so if you already installed it for that, screen sharing has what it needs.
If the installation gives you trouble, our support team is in the online chat.
Frequently asked questions
Can I share my screen if I present from Linux?
No. The plugin needs Windows or macOS, so on Linux it does not run and screen sharing is not available, which technical requirements notes alongside the other platform limits. Screen sharing is the one mode that asks for a program of ours, because camera and microphone go out through the WebRTC built into your browser.
I already installed the plugin for alternative broadcasting. Do I need to install it again?
No. The same plugin powers our alternative broadcasting technology and screen sharing, so if you already installed it for that, screen sharing has what it needs. How to share your screen during a webinar walks through the rest, from the download inside the room to choosing a monitor or a single window.
The app is installed on my Mac but nothing shares. What is missing?
Almost certainly the system permission. On macOS there is one extra step, because the app also needs permission under "Screen & System Audio Recording" in your system settings before it can share anything. How to share your screen during a webinar walks through the whole sequence.
Can attendees record what I share?
Yes, and encryption does not change that. Everything the software sends is encrypted with TLS on the way, and only people who are in the webinar room and hold the right access rights can see it, but anyone who can see your screen can also photograph or record it, exactly as they could in a meeting room. So close anything you would not want in the recording before you start sharing.
My shared screen looks worse than I expected. What affects it?
Your own computer and your internet connection, mostly. The program is built to send a sharp image of your screen, and it gets there by keeping the amount of transmitted data down and using advanced compression, which avoids delays even when the system is under load. However hard we work on the encoding, an old or slow machine or a weak connection produces a worse picture than you were expecting.
