This section details how connectivity over the 6 GHz band benefits Enterprise Wi-Fi serving any kind of Latency-Sensitive Applications.
An enterprise Wi-Fi that is serving any kind of Latency-Sensitive Applications benefits greatly from devices’ connectivity over the 6 GHz Band. Using the 6 GHz improves the user experience in any scenario where quality and reliability of the network are paramount to the real-time experience, especially in ecosystems that include higher density and a larger number of users and application sessions.
Latency-Sensitive traffic takes advantage of the OFDMA Uplink and Downlink technologies of the 802.11ax. In most deployments of 6 GHz, the channel serving the connected devices uses an 80 MHz channel width. Given that streaming traffic uses a relatively small Resource Unit (RU) Tones of the OFDMA, there is a likelihood that many separate subcarriers are utilized in accessing the medium without any contention and are able to efficiently fill vacancies of the spectrum.
The efficiency of the OFDMA allows the ecosystem to support a much larger capacity of such applications while keeping the traffic performance intact and maintaining the stable performance with lower jitter, latency, and packet loss for all the connected devices. Without OFDMA, a lower density of connected devices can maintain good quality.
Consider the following real-world scenarios of Voice deployments, which apply to other media apps. Note that the Voice examples given here use a standard metric of Mean Opinion Score (MOS), in which, in most Voice Applications scales, a value of 4.3 and above is “Excellent”, between 4 and 4.3 is “Good”, and anything below the value of 4 yields noticeable impact to the User Experience (a.k.a. “Fair”, “Poor” or “Bad”).
In one scenario, multiple Zebra Wi-Fi 6E-capable devices are connected to a 6 GHz channel, and while most of those devices handle ongoing Voice Calls, some others handle background traffic of data Applications. In this situation, the advantage of the default deployment of 6 GHz using 80 MHz bandwidth allows for significantly more ongoing Voice Calls to maintain the same high level of MOS value without degradation across all devices, compared to a bandwidth of 20 MHz.
The following chart shows a test result example of the above scenario: the chart depicts a MOS value of an increasing number of devices handling Voice Calls at the same time, each facilitating a call with a remote peer, while several other devices handle background traffic (not shown). As shown in the 80 MHz plot, the average MOS value for each given number of Voice Calls remains consistently “Excellent” as the number of Calls increases. Conversely, in the 20 MHz plot, the Average MOS value is Excellent in up to 8 Calls, then decreasing to Good in 10 Calls, and further degrading to Poor and Bad when increasing the number of Calls to beyond 10.
6 GHz Client MOS Score 20 MHz vs. 80 MHz
In another deployment scenario, a Voice Solution is deployed on a mixed fleet of device types at the same venue. Some are Zebra’s Wi-Fi 6E-capable devices, and others are Wi-Fi 5-capable or older, which don’t support Wi-Fi 6/6E altogether, thus are not OFDMA-capable.
In some of the times and places in the venue where the 6 GHz coverage is either insufficient or not supported by the WLAN at all, Zebra’s Wi-Fi 6E-capable devices are connected to the 5 GHz coverage that is also used by the Wi-Fi 5 devices, and those Wi-Fi 5 devices are either also running Voice Calls at the same time or any data application. In all, the entire traffic over the 5 GHz of all connected devices with the same AP is utilized over a 20 MHz width of the channel.
A 20 MHz channel width is the common and recommended practice in Enterprise 5 GHz WLANs for Voice, due to 5GHz being limited by a smaller overall spectrum and under the regulations of Dynamic Frequency Selection (DFS) imposed on large portions of the spectrum. In all, the 5 GHz needs to be sliced to a narrower channel width.
In ‘other’ times and places in the venue, if 6 GHz is supported by the WLAN and its coverage is sufficient, the Zebra’s Wi-Fi 6E-capable devices are connected to the 6 GHz coverage. In this situation, the Wi-Fi 6E-capable devices support Voice Calls on the 6 GHz/80 MHz band, while the Wi-Fi 5-capable devices support Voice Calls or data applications on the 5 GHz/20 MHz band.
In this mixed fleet scenario, it is expected that if and where 6 Hz WLAN is supported, the Zebra’s Wi-Fi 6E-capable devices will maintain the MOS values as depicted in the previous chart’s 80 MHz orange plot.
