In a BlueJeans Event, an attendee joining via browser is expected to see a delay of about 20-30 seconds from the actual Live event. The reason factoring the delay is as follows:
- The attendee's player is receiving a Live broadcast of the running event.
- For broadcasting over the Internet, we use Live streaming over HTTP (using HLS protocol)
- The stream is first transcoded by our servers into multiple Bitrates (having resolutions 240p, 360p and 720p). This helps in Adaptive Bitrate Streaming, in order to cater the Bandwidth available at user end and ensure continuous playback of the stream.
- The stream is then relayed over a Global CDN (Content Delivery Networks) to ensure the end user connects to a local CDN server for good bandwidth and negligible loss.
- Once the stream from the CDN hits the player on the attendees' screen, the player buffers the stream for few seconds (similar to Youtube i.e around 5-6 seconds) to deliver a smooth playback experience.
So overall, the stream originating from our servers and relaying over a CDN to reach a browser attendee constitutes to the delay.
A Live Broadcast is generally suitable for an Event, where a large number of users across the globe are viewing/ attending the event & not participating in it, so for them the delay would generally not matter.
- This is a limitation of the streaming technology and cannot be reduced. All popular streaming sites such as Youtube live, Twitch tv etc have a delay of 30-40 seconds on their stream for reason similar to ours.
- Room system & PSTN dialled-in attendees will have a real time experience as the stream is served directly from our servers in single bitrate and no CDN is involved.
- Joining from both computer and telephone simultaneously might lead to lip sync issues.