VoWifi Overview

“Wi-Fi” is a trademark of the Wi-Fi Alliance and the brand name for products using WFA programs based on the IEEE 802.11 family of standards.

When I worked in R&D we used to say that patents are like hostages. The advantage is that we can create them ourselves.  In April 2009, 14 technology companies agreed to pay CSIRO (Commonwealth Scientific and Industrial Research Organization in Australia) $250 million for infringements on CSIRO Wi-Fi patents. Hence Australians labeled Wi-Fi as an Australian invention, though this has not been accepted by everyone without objections (especially in US). CSIRO won another $220 million settlement for Wi-Fi patent-infringements in 2012 with global companies in the US required to pay the CSIRO licensing rights estimated to be worth an additional $1 billion in royalties. Guglielmo Marconi or Joseph Fourier would be bambillionaires these days.

In our post the Wi-Fi refers to a WLAN access to ePC, both trusted over S2a interface or untrusted over S2b interface (3GPP TS 23.402). The VoWifi is then a voice and video over Wi-Fi IMS profile, defined in GSMA IR.51. If you are familiar with VoLTE (IR.92 and IR.94), the VoWiFi defines the same set of services, just over a different access network. The service network – the IMS – remains the same. Sure we need to be more sensitive when it comes to muli-device scenarios or access transfer.


This article is focused on the technical aspect of the VoWifi definition. Would you like to know a bit more about why to deploy the VoWifi, check out this post written by Alberto Diez.

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News: Li-Fi – pushing the IoT forward

Do you switch-off  your smartphone or wifi, when you go to sleep? Many people do. I’m not going to discuss if the waves have any real effect on our health or psyche. But undoubtedly in the industry with more and more active devices we have to think about possible interference. Especially in the electromagnetic sensitive areas such as in aircrafts, hospitals or chemical plants.

Fortunately there is a new technology which doesn’t utilize the radio waves but still belongs to the same standard family 802.11 as Wi-Fi. Li-Fi is a bidirectional, high speed and fully wireless communication technology, that uses light from light-emitting diodes (LEDs) as a medium. The visible light spectrum is 10,000 times larger than the entire radio frequency spectrum. On the other hand the light waves cannot penetrate walls which makes a much shorter range. Still the direct line of sight isn’t a must. A light reflected off the walls can achieve 70 Mbit/s!

So what is the real data rate? The Estonian Velmenni startup  just announced that they are able to send data at up to 1GBps. That means 100-times faster than via Wi-Fi. As the British scientists have even reached the data rates of over 10 Gbit/s, which is more than 250 times faster than current broadband, we can expect further improvements in the future.