Our main concern here at Talkdesk is to be able to provide you with a reliable product so that you can make and receive calls with the best possible audio quality.
The biggest factor in determining call quality is to make sure you connect your computer using an ethernet cable instead of Wi-Fi. While Wi-Fi offers convenience, it can lack reliability for voice communications.
This article explains the technical details of why, for Talkdesk main web application, we don’t recommend Wi-Fi and why ethernet is best.
Note: When using Talkdesk Mobile Agent application, we recommend Wi-Fi speeds upwards of 100 kbit/sec for voice calls or a network connection with a minimum 3G data signal.
What is “Voice over IP”?
When you speak, the microphone picks up your voice, and your computer then converts this analog information into a digital stream. This stream is chopped up into packets of data. It’s these packets that then head out to travel on the vast highway that is the internet. If those packets arrive quickly, and in the right sequence, then you’ll have a great quality call. (The same in the reverse direction, the voice of the person you are speaking to, needs to reach you too).
What happens to those packets?
Ordinary internet traffic uses something called TCP (Transmission Control Protocol). This includes error correction and requests for retransmission is packets are missing or incomplete. So even if you encounter some bumps along the way, the data gets back to you intact. But audio packets are transmitted using “UDP” instead of “TCP”, because time is of the essence for a live conversation! With this method of transmission there is no guarantee of delivery, sequence, or protection for duplicate packets, so a good connection is vitally important.
So what’s the deal with Wi-Fi?
To simply put it, Wi-Fi was not designed for voice. To explain a little better, Wi-Fi uses unlicensed radio spectrum so you don’t need to apply for a government license to use it. You can just buy a router and let the Wi-Fi waves flow. Unfortunately, because this is unlicensed spectrum, other devices like microwave ovens which operate on the same frequency can interfere.
Making it even worse most routers are still operating at 2.4GHz, where there are only 11 channels available for a standard Wi-Fi connection. When you do a search for Wi-Fi networks you will almost certainly encounter many many more networks than just yours. All of these networks are interfering and overlapping with each other, which can result in lost packets. In order to try and make Wi-Fi work at all and cope with the interference, there’s a lot of error correction and retransmission of data going on behind the scenes.
If you’re making or receiving a phone call which by its nature is real time and in two directions, this solution is just not workable. It means the latency on a call may be too high, introducing a delay between each party hearing each other. That means a conversation between two people gets frustrating, with each party speaking over each other.
As well as the problem that individual packets may get lost altogether, there is also the problem of packets that arrive out of sequence (known as jitter).
For a good quality phone call there is a small tolerance for things like latency, packet loss and jitter. You can maximize your chance of a better Wi-Fi connection by using a 5GHz router, as this newer band is less congested, but it’s still subject to the same basic limitations.
Conclusion: Ethernet’s Best
The problems of Wi-Fi congestion and error correction is why we recommend Ethernet. It removes all of those challenges. By plugging in a cable, your packets of data travel uninterrupted to your router, and then out over the internet.
- Packet loss: Your audio is converted and sent over the internet as packets of data. If some of those packets don’t arrive at the destination you’re going to have a very poor call experience.
- Latency: Latency is the time it takes for data to be sent and received. If the latency is too high voice calls become unworkable due to the delay.
- Jitter: Jitter is the variability of Latency. It measures how many data packets arrive in the wrong order. For a voice call it’s absolutely crucial that packets of data arrive in the right sequence.