Network requirement

Hi,

It's hard to say. High bandwidth is not the most important for real time communication (RTC) it's more important with an low latancy, jitter and packet loss. So even if you but a 100Mbit connection there could be high latency and that would give users a worse experiance than a 10Mbit connection with low latency.

There is a tool from Microsoft, Skype for Business Network Assessment Tool, you can download to see if your current connection is good. This will measure packet loss, latency and if packets arrives in the correct order. This tool will say if your connection fails or pass these tests. In the latest version you can also see if your firewall is blocking ports needed by Skype.

https://www.microsoft.com/en-us/download/details.aspx?id=53885

Run this tool on different times of the day.

Another consideration is how stable the connection is. It's common that you can get a more stable connection with better SLA if you pay more.