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What it takes to build real-time voice and video infrastructure

In this series, WebRTC expert Tsahi Levent-Levi of provides an overview of the essential parts of a real-time voice and video infrastructure—from network to software updates. Check out his informative videos and read how Agora’s platform solves the challenges so you can focus on your innovation.

1.1 Welcome

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Category: Chapter 1: Introduction

Get an overview of the topics included in this video series, including real-time communications (RTC), real-time engagement (RTE), webRTC (web-based RTC), and all of the technologies necessary to enable live, interactive voice and video communications.


Hi, and welcome to this course about RTE, RTC, and WebRTC. RTE stands for real-time engagement. Whereas RTC stands for real-time communications. Then we also have WebRTC, web real-time communications. 

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In this course, we’re going to touch all of these areas, and try to figure out what that means to us. My name is Tsahi Levent-Levi and I’m the author of I’m a consultant and analyst in the digital communication space, where I focus on web RTC. CpaaS Cloud communication platform as a service, as well as less machine learning and artificial intelligence. In communication specifically, I’m also the co-founder and CEO of a company called TestRTC that handles and manages self service solutions for monitoring, testing and support services around WebRTC based applications.  

So why RTE and why now? Exactly. We’re talking about real-time engagement. What we’re trying to understand is why is it important now, why this course. So I took the liberty of going to Chrome status. This is a website that shows different API calls inside Chrome, and how much popular they are, how many page views that are running chrome go and use these API’s. This is something that can show the usage of WebRTC. It is a percentage of pages that have called get user media over time, and get your resume get user media is usually the starting point of a WebRTC session, which is again, part of real-time engagements, we’ll see that later, when we will stick about speak about devices and about web RTC.  

But what we see here essentially, is that what we had over time, throughout 2019, for example, is roughly 0.04 or 0.05% of the pages that were loaded in Chrome, are actually called Web RTC. Then when the pandemic started, we see an increase a hike in the use of WebRTC would go up to 0.2%, and then 0.4, and even 0.6. At its peak, we then go down and back up again, what we can say is that this is something that is here to stay, we’re going to see an increase in real-time engagement services. And in these use cases where as they proliferate, and are used more by more people. We’re not going back to the 0.04 anytime soon, we’re going to stay at four or five times that at the very least three times the engagement is important. We see a lot of vendors and startups and entrepreneurs going in trying to build services in that space. But the thing is that there is a huge learning curve here. You need to learn a lot of different disciplines, media, compression, networking, signaling in a lot of other aspects. And this is exactly what we’re doing going to touch in this training.  

So what are we going to do exactly? There are several chapters there is to these training. There is introduction one: what we’re doing now. The next lesson is going to explain what real-time engagement is exactly and how we got there. The following chapter is going to be about challenges. The challenges of building such a solution in what it means to create such platforms. We’re then going to touch each and every aspect and each and every domain. In real time engagement platform. We will start from the client, and the actual devices, the devices that users end up using when they want to join these sessions and engagements. From there, we’ll look at media servers, the components that are needed for recording, group sessions, and broadcasts. We’ll discuss media processing, how media gets sent over the network. What should we do there and think about when we send send media over network. Then from there, we’ll discuss signaling, how do we exactly find others on the network? What do you want to convey and do besides just audio and video. Finally, we’re going to talk about maintenance.  

We’re not going to build the platform now and forget about it. There is a lot of things that we’ll need to do over time, all the time when we have such a platform running. So let’s look at get started and see what it gets us. Thank you for being with me and I’ll see you in the next lesson.