Peer-to-peer video delivery in Engagestream
Last updated: October 9, 2026
This article is for event organisers and customer contacts. It explains what peer-to-peer delivery is and what your organisation needs to do to use it. The technical requirements for your IT or network team are in the companion article Network requirements for peer-to-peer video delivery .
What it is
Videosync can deliver event video to your viewers using peer-to-peer (P2P) delivery, provided by our partner System73 with their Edge Intelligence technology. Viewers watching the same stream on the same office network share video segments with each other over the local network, so the stream crosses your internet connection a few times instead of once per viewer.
It works for live streams and for recordings. The saving comes from people watching the same thing at the same time, so it matters most for live events, and for recordings many people open at the same time, such as one published straight after the event.
P2P is a separately priced add-on. It is enabled per live channel, on request, for customers who need it. It is not switched on by default.
When you need it
P2P pays off most when many viewers watch the same event from inside the same corporate network, for example an all-hands meeting or a town hall watched from the office. There are two gains.
Your connection stops being the limit. Every viewer normally downloads a separate copy of the stream. A multi-bitrate stream can take up to 5 Mbps per viewer at the highest quality, so a 1 Gbps office line carries around 200 viewers before it saturates, on a connection also carrying everything else the office does. With P2P the load moves to your local network, which has far more capacity.
Your viewers get a better stream. Segments that come from a colleague on the same network arrive faster than segments pulled across the internet, and the uplink is no longer contended. Players hold a higher quality for longer and interrupt less, for everyone watching, not only the people who would otherwise have been the ones buffering.
P2P works wherever viewers share a network, so it is the concentrated audience that gains. Anyone watching from home or on a mobile network is served by our content delivery network (CDN) as usual.
Nothing for your viewers to do
- The player and event page look identical. Viewers install nothing and change no settings.
- Playback is never at risk. Any viewer who does not reach a peer simply streams from our CDN, exactly as they would today, with no error and no delay.
Browser requirements
P2P delivery is built on WebRTC, the same browser technology used for video calls, together with standard HTML5 video playback. All current versions of Chrome, Firefox, Edge, and Safari support it on desktop, and so do Android browsers. On iPhones and iPads, support depends on the browser’s media capabilities and may not be available in every configuration.
A browser that does not support the required features simply receives the stream from the CDN as usual. Viewers do not need to install anything.
For the exact minimum browser versions, see System73’s SDK requirements .
What is needed from you
- Involve your IT or network team. P2P needs a few outbound connections allowed through the firewall and direct communication between devices on the local network. Forward the companion article Network requirements for peer-to-peer video delivery to them.
- Agree on a test event with Videosync. Before your first real event, we run a short test stream with a handful of viewers on your network. In most cases P2P works with the default configuration. If it does not, the test data shows where the bottleneck is, and we pass System73’s recommendations to your network team.
Data and privacy
When P2P is enabled, System73 acts as a sub-processor for Videosync. The viewer’s browser reports playback and connection analytics to System73 so that peers can be matched and performance monitored. The data points that may be considered personal data are the viewer’s IP address and a unique device identifier, together with technical details such as browser type, connection type, and approximate location derived from the IP address.
The video and audio stream itself is never sent to or stored on System73’s servers. Viewer names, e-mail addresses, registration details, and other Videosync account data are not shared with System73.
For the full list of data points, see System73’s Edge Analytics data model . For contractual details and the list of sub-processors, see the Videosync security statement .
Frequently asked questions
Does P2P slow down viewers’ computers?
No. Sharing video segments uses a small amount of upload capacity on the local network and negligible CPU. Viewers will not notice it.
Does it work when viewers are connected over VPN?
It depends on the VPN configuration. Viewers on a VPN often cannot see each other on the local network and are then served from the CDN like any remote viewer.
Does it work on phones and tablets?
Yes, in the browser, within the browser requirements above. Android devices on the office Wi-Fi participate like any other viewer, provided the Wi-Fi network allows devices to communicate with each other. On iPhones and iPads, support depends on the browser; devices that cannot participate are served from the CDN as usual.
Can we see whether P2P worked?
Yes. Videosync sees statistics for each P2P-enabled event and can report after the event how much of the traffic was delivered peer-to-peer versus from the CDN.
What happens if the firewall blocks P2P?
Nothing visible. Viewers receive the stream from the CDN, and you simply do not get the bandwidth savings. There is no risk of the event failing because of P2P.
Getting started
Contact your Videosync contact person or support_CWC@euronext.com to enable P2P on your live channel and to schedule a test event.