Our goal for the back end of the TokShow application was to make it as simple as possible while supporting a couple thousand people.

The biggest concern for performance was moving a new fan on stage. When that happens, everyone in the TokShow needs to hit the server to get the connection ID of the next fan. We thought the ‘aha’ moment of a fan meeting the artist for the first time would be a major part of the experience, so making the transition smooth and simultaneous for all of the viewers was critical.

To keep things simple, we used PHP and MySQL on the server. There is very little state saved for the application. We basically need to know:

1. Who is on stage
2. Who is in the line
3. Whether the show has started yet
4. What time the show is scheduled to start.

We had one PHP file to wrap our reads and writes to the server, and that’s about it. For our TokShows we needed only one PHP server, which also hosted the database.

Building the TokShow app gave us another great opportunity to test our API in a real-world app. And, sure enough, we discovered some additions for the OpenTok API.

Not all clients using the app and participating in the session have the same audio-video capabilities. Some clients use older versions of Flash Player or hardware that does not support acoustic echo cancellation. The acoustic echo cancellation feature was added in OpenTok v0.91.18 (in June), and it works great. It pretty much eliminates acoustic audio feedback. We wanted to build an app that allowed the administrator to see if a potential participant (fan) had acoustic echo cancellation supported on their machine. However, the OpenTok API did not provide that information … so we added it. And the new API includes other information on the quality of each stream in the session. In addition to acoustic echo cancellation support, the API provides other information about the publisher of a stream, including the upstream bandwidth, whether the microphone and camera are enabled, and whether H.264 video is supported. These enhancements were added in the November 10 release of the OpenTok API (v0.91.35).

There are a number of huge challenges being a platform company, as the product we build has to work under many conditions. One of those major challenges is the issue of scaling a realtime communications platform to support both one-to-one conversations and also 5000+ participant talk shows. Now some people might say “Doesn’t YouTube already let thousands of people view a video?” Yes, but the difference is that YouTube is about consuming and OpenTok is about face-to-face.

Someone once told me that if your customers are forcing you to move so quickly that you’re constantly on the brink of crashing, you’re likely onto something big. I’m starting to believe that more and more with each day.

In the last two months the TokBox team has been moving at record speeds. We’re doing something right. In fact, I think we’re doing a lot right. The small pieces that we’ve been pushing on for a long time are starting to come together as we had imagined and hoped they would.

Most recently, we’ve been working on one of our newest plug-n-play apps, TokShow, which has been the cause of much of this craziness. TokShow allows musicians, politicians, celebrities or really anyone to host a live conversation with their followers on any web site. Think MTV’s old-school show TRL hosted by Carson Daly. Your favorite band takes the stage to field questions from the audience about their upcoming album or tour.

With TokShow, that type of fan and celebrity interaction is now possible online to the masses, not just to the crowd lucky enough to be in the studio.