GSX Blog

Skype for Business Voice, is UDP always better than TCP protocol?

Posted by Jean-Francois Piot on Tue, Mar 13, 2018

illuBlogskype2.pngSkype for Business Online natively works with two main protocols, UDP and TCP. Microsoft, and most of the other VOIP solution providers, recommend to choose UDP over TCP.

But, is it always better? What is the impact and what are the advantages of one protocol over the other, specifically in your environment?

In order to help answer this question, we conducted several experiments on different types of networks. This was the only way to really assess how the voice quality of a specific Skype for Business user is affected by these protocols.

You might be aware that UDP is the fastest way to deliver packets on a network. However, it is not the most secure way. UDP needs a wide range of ports to be opened. TCP does not.

On the other hand, UDP is way less sensitive to packet reorder issues and low bandwidth environments.

To assess the differences, we used the GSX Robot Users to perform Skype for Business calls.  We collected data for one week, with calls made every five minutes. This represents 2016 calls.

The environments were:

  • Stable environment, good network, low jitter and constant bandwidth
  • Network environment with 15% packet loss
  • Network environment with high latency (200ms)
  • Network environment with 10% packet reorder ratio
  • And finally, an environment with a congested network

Truth be told, it turned out that TCP is not always the worst protocol to choose; it all depends on how good or bad the network quality is.

Let’s have data do the talking: You can hear about the results on our new RoboTech: UDP vs TCP, myth and reality of Skype for Business Voice quality.  


Tags: Microsoft, Hybrid cloud monitoring, Office 365 monitoring, Skype for Business, cloud performance, skype for business monitoring, office 365 health, office 365 performance, fixing office 365, Skype