I thought it interesting to making some comparisons between a VLC system a WiFi system. This comparison implies that VLC and WiFi are competitors in this space, although this may prove not to be the case.
In marketing we often see comparisons of competing products based on feature sets, with the advertised product always having more ticks than the competitors. I tried a similar exercise between WiFi and VLC but felt it better to score them on a star based measure (3 being best) rather than a binary measure. I work in the VLC space so I may have a certain bias, but I have tried to be fair. If I have not but it stimulates some debate then all to the good.
I justify the scoring as follows. 1) Obviously WiFi is a more mature technology, 2) Similar speeds (up to 1Gb/s) are possible by either, 3) The range of VLC is relatively short (few meters), whereas WiFi can achieve 10s of meters. 4) WiFi needs external power but VLC already has power available for the LED lamp. 5) WiFi backhaul is provided by plugging into an Ethernet system or directly into the broadband connections, for VLC Ethernet or powerline communications is used. 6) VLC does not require the RF and antenna front-end and also the illumination power is also used as the transmit power. 7) WiFi uses encryption for security but it is difficult to constrain the data transmission within a set area, whereas VLC by its nature confines the data to areas which are intentionally illuminated. 8 ) WiFi causes a lot of co-channel interference and deploying more WiFi nodes does not increase capacity linearly, for VLC interference is confined and so the re-use efficiency is much greater. 9) For non-line-of-sight links the WiFi signal is degraded by signal attenuation causing lower data rates. For VLC if there is no line-of-sight or good reflected signal then the communications link may fail. 10) The bill of materials for WiFi must include all of the RF and antenna components, but none of these expensive components are required for VLC.
On reflection I am going to suggest that VLC is complementary to WiFi. WiFi might be used for wide-area coverage within a building. Many VLC nodes can be used for short range high data rate links. If one link is unavailable, for example due to shadowing, the WiFi may provide the back-up.