Bandwidth Requirements of VOIP Systems

February 14, 2017

Written by: Marshall Nye, Dev Ops and Technical Support Specialist

How much data will a voip system use?

X&XYZ phone call ringing incoming

To answer this question, we must understand the answers to two others:

  1. What is the internet speed that is required for the VOIP solution to run well?  Think of “will this outlet have enough power to run the microwave”

explosion cooking wine bottle microwave        2. What would be an average consumption of data over a month while using VOIP? Think of it how much electricity your house uses a month.

In hopes of getting you a concise answer, we’ll define a few terms so we’re all on the same page.

  • Broadband – A high-capacity transmission technique using a wide range of frequencies, which enables a large number of messages to be communicated simultaneously (think of what replaced dial-up).
  • Bit-rate – the number of bits of data that are conveyed or processed per unit of time. The rate at which data is processed or transmitted.
  • Bandwidth – the bit-rate of available or consumed information capacity expressed typically in metric multiples of bits per second. Somewhat analogous with bit-rate
  • Megabyte – Abbreviated as MB – Is a unit of measure to define size of data (an old mp3 was around 3 megabytes)
  • Megabit – Abbreviated as Mb – A unit of measurement to define the size data. Equal to one eighth of a megabyte.
  • Megabits per second – Abbreviated as Mbps – A unit of measurement to define the rate at which data is transferred.


Answering Question 1

For multiple kiosks running at a site, the recommended speed requirement (Bandwidth) would be 5-10 Mbps.

For one kiosk the recommended speed is 1 Mbps

Answering Question 2

We can answer this by making a few assumptions:  Let’s assume you have a kiosk that makes 5 calls a day, and each call lasts 5 minutes. This is a very generous assumption, so it will give us a large margin of error. We will assume that one kiosk will consume data at a rate of 1 megabit per second

Data consumed per call:

1 minute = 60 seconds

5 minutes x 60 seconds = 300 seconds

1 Megabit per second x 300 seconds = 300 megabits

300 megabits per call x 5 calls a day = 1,500 Megabits or 188 Megabytes, per kiosk, per day.

(All of our kiosks use the same VOIP program, so their data consumption rates will be identical. Assuming the use remains the same, they would use the same amount of data in a given period of time. So to calculate the daily consumption of multiple kiosks, simply multiply the number of kiosks by 188 Megabytes.)