Video and Multimedia Applications

The original Wi-Fi protocols were designed to integrate IT equipments wirelessly into existing wired networks. Today, wireless access cards are ubiquitous, not only in laptop computers but also in desktops, smartphones, tablets, e-readers, connected Cheap Curved TV, VoIP terminals, etc. New usages have emerged and put the Wi-Fi technologies under a strong pressure. 

While being ubiquitous, the Wi-Fi protocols present serious flaws for certain types of applications, even with the latest 802.11n addendum and the promise of insane bit rates. The Wi-Fi access protocol inherently induces latencies and latency variations, which make it incompatible with a smooth transfer of synchronous streams like voice and video. Even a simple VoIP communication with its tiny 10 kbps requirement is at risk.

Comsis has developed a number of mechanisms which greatly improve the overall quality of service of synchronous streams. They fall under two categories:

• Advanced MIMO techniques ensure that the radio information makes its way to the receiver whatever the multipath conditions encountered in a typical indoor environment. Comsis was one of the first companies to offer MIMO solutions a decade ago, long before it was adopted by the Wi-Fi standards. Experience does matter.
• A special medium access mechanism nicknamed QoS-WiFi grants a fair access to the medium to any network node with an optimized latency. All the nodes don’t need to be equipped with QoS-WiFi to benefit from short access times and small latency spread.  The entire network benefits from the improvement with just one QoS-WiFi node, with full interoperability preserved.

Images speak for themselves. The screen captures below come from the same wireless video stream (same severe radio environment), without (left) and with (right) the QoS enhancement features developed by Comsis. Click the image for a larger view.

The QoS improvement mechanisms developed by Comsis find their place in applications requiring low error rate, low latency, and low latency spread (jitter). This includes:

Resources

• White paper: Efficiency Optimization in Wi-Fi Networks with Enhanced QoS.
• Inquiries: sales@comsis.fr