What does a “live” broadcast actually mean? After Janet Jackson’s infamous “wardrobe malfunction” at the Super Bowl, all Super Bowls have been actually broadcast with a five-second delay in case something goes wrong. It’s fairly common in a lot of “live” TV, actually – many programs have a few seconds between something actually occurring and it showing up on our screens. We expect a telephone call where we’re talking to someone directly to be instantaneous; we don’t necessarily expect events broadcast around the world to be actually instantaneous, just close enough that we feel like we’re experiencing a live event with no possibility of spoilers. But what does that mean in terms of communications at work or school?
We’ve recently all become far more comfortable with video communications of all kinds as part of daily life. From one-on-one talks to mass lectures and townhalls, we participate in a lot of live events by video now. But did you realize that “live” does not always mean in “real-time”? When does it matter, and how do you choose?
What Does “Live” Mean in “Live Streaming”?
When referring to live streaming, it is important to understand there are multiple different definitions of “live”. Therefore understanding these different definitions – and crucially – how they apply to your specific requirement, is key to deciding which to choose.
Webcasting platforms (such as Kaltura Townhalls) leverage live technology to broadcast video (similar to Netflix, YouTube, Facebook, etc., as well as “live” TV), whereas technologies such as Zoom, MS Teams, Blue Jeans, WhatsApp video, Facetime, and Kaltura Meetings use real-time communications.
“Real-time communications” is primarily used where individuals, or groups of individuals, would like to have a video conversation with one another. This is often referred to as one-to-one or many-to-many streaming. “Broadcast”, on the other hand, is primarily used for instances where the presenter (including any additional media, such as slides, Q&A, polling, etc.) is streamed out to large numbers of viewers. This is often referred to as one-to-many streaming.
When Do You Choose Broadcast and When Do You Choose Real-Time Communications?
The benefits of broadcast are that you can have a very large number of concurrent video recipients, for example many tens or hundreds of thousands of people, watching the webcast at the same time. This is because of the type of technology used for broadcasting or webcasting adapts to the bandwidth of the recipient viewing the video, meaning even viewers with low bandwidth (or who live in low bandwidth areas) get a good viewing experience. The downside to broadcast is the video stream needs to be processed before it can be viewed (to make it adaptive to the bandwidth). The time is takes to perform this processing means there will be a delay of about 20-30 seconds between the time of the presenter and the time it is received by the viewer due to the video processing, hence this technology is not used for face-to-face video chats. (This is different from the intentional live delay on TV.)
The benefits of real-time communications is there is no delay with the live stream with low quality , so you can have a face-to-face video chat, in much the same way as you do via a telephone (without the face, of course). The downsides are that it is not adaptive to the end viewer’s bandwidth, so those with low bandwidth will often get a bad experience of the video, or no video at all (this is why you will often experience sound and pixilation problems with face-to-face video chats). Another limitation is that you can typically only have a small number of concurrent people on the call, for example the small hundreds, especially when everyone is using a shared internet connection. For this reason, real-time technologies are typically not used for large scale webcasts.
Both real-time and broadcast are quite handy technologies. The key is knowing the difference and the pros and cons of each to ensure you are always using the right solution for the right need.
Want some tips on real-time and live communications? Kaltura offers a live tech stack that supports from 1:1 all the way to unlimited viewers.