Adam Walsworth

Digital Media Troubleshooting Tip Of The Day: Bitrate Transition Testing

Blog Post created by Adam Walsworth Employee on Sep 3, 2015

Todays digital media world has seen many advances in the ability to seamlessly transition between bitrates when available bandwidth fluctuates. Gone are the days when lower bandwidth results in long rebuffering delays while the stream tries to switch bitrates. The solution given today will help you test the switching that occurs when available bandwidth becomes lower or higher than the currently streamed bitrate.


First you will need a bandwidth limiting tool. There are many available options out there but for this test we will be using Netbalancer which can be downloaded from here.


The great thing about netbalancer is its ease of use. You simply select the process that you want to set a bandwidth limit on, right click and select create rule. For this example we will limit the bandwidth of Firefox.



Under download priority select limited and change the KB/s to match the bitrate you want to switch to. In this case we want to push the bitrate down to a 300 kbps stream so we will set the limit to 40 KB/s. Using this tool you can change the bandwidth limit quickly by simply changing the number and selecting apply. After doing this you can monitor your video stream transition using your own player or one of our own Akamai debug players. In this case you can see that the bitrate has switched to the lowest available rate.



For even more in-depth analysis you can also combine this tool with a proxy monitor like fiddler or charles to watch the requests change from 1 bitrate to another.


Stay tuned for my next article showing step by step instructions on how to setup a mobile device to utilize a proxy for testing videos and capturing errors.