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Bolstering Bandwidth with Dual-Channel Wi-Fi

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Wi-Fi traffic flow in a dual-channel configuration.

Dual-Channel Wi-Fi is one potential solution to growing competition for home bandwidth.

Credit: CableLabs

It's a scene that has been repeated in homes many times over the past few months, due to the stay-at-home orders in place around the world.  Mom tries to hop on a work Zoom videoconference call, while Dad has logged onto a Facebook video chat to check in with his elderly father. At the same time, their 16-year-old daughter is trying to stream Dirty Dancing via Netflix, while the couple's 12-year-old son is playing Fortnight on Xbox Live with several online friends. With all of this Internet activity, it's likely that one or more family members has seen the performance of their connections suffer, due to the strain of multiple devices competing for the same bandwidth.

One potential solution to this competition for Wi-Fi spectrum has been developed by communications equipment maker Edgewater Wireless and nonprofit research and development lab CableLabs. The firms' Dual Channel Wi-Fi solution utilizes spectrum slicing to create one or more downlink-only data channels, which can be combined with a standard, bi-directional channel to reduce competition for bandwidth, known as contention, as well as reducing data latency, the amount of time it takes for a signal to make a full trip between the device and an Internet access point.

Edgewater's patented approach is called Multi-Channel Single Radio (MCSR), and is designed to deliver multiple, concurrent channels of transmission and reception from a single IEEE 802.11ac or 802.11n Wi-Fi standard-compliant radio. The company's customers are primarily in the enterprise market now (grocery giant Kroger is a client), but Edgewater Wireless says it is now also focusing on the residential market via cable services providers such as MediacomCable.

In order to use the technology, both the access point and at least one device on the network (which can be an Internet-connected television, set-top box, or gaming console) must be equipped with dual-channel chipsets. The existing primary Wi-Fi channel is designated for upstream and small downstream data packets, while the new channel or channels are used for large downstream and time-critical data, such as video or audio. To ensure the optimal use of bandwidth, a Traffic Filter Profile triages the data based on packet size, source IP, source port, destination port and protocol type and sends data to the appropriate channel, reducing congestion.

"If you dump a lot of traffic on [a Wi-Fi network] and they are all operating on variable speeds, you get brought down to the slowest [speed], and that's what's happening today in people's homes," says Edgewater Wireless president and CEO Andrew Skafel. "What we do is we slice up the spectrum, so you put more [channels] on it."

Skafel says Dual Channel Wi-Fi technology requires an Edgewater access point that incorporates Edgewater's MCSR chipset. As long as at least one end device in the home is equipped with an MCSR chipset, the entire network can benefit, without needing to upgrade to new hardware. That's because the system will automatically optimize packet-heavy traffic among the downstream-only and bi-directional channels on the MCSR-equipped devices, which frees up bandwidth for standard Wi-Fi-equipped devices to operate on the original bi-directional channel.

Additionally, because the technology runs on top of the existing 802.11ac and 802.11n standards, it can utilize the same security protocols that are currently available. According to Phil Solis, research director for IDC's Enabling Technologies team, "I would assume that the same security protocols that are in use today [would be sufficient], and then WPA3 going forward," citing the 2.0 version of the Wi-Fi security protocol that was released in December 2019. 

Further, Skafel notes that the platform supports a real-time spectrum security monitor, which can be used to identify outside interference or the presence of hackers. "Let's say someone's turned on a microwave or a baby monitor, and you'll know what that looks like, or the monitor could allow you to identify rogue hackers trying to get into your network," Skafel says, noting that spectrum interference pattern monitors can be developed to run on the Dual-Channel wireless technology by cable companies or access point manufacturers as a feature differentiator. In lab tests, Edgewater found that utilizing three Dual Channel-equipped devices and one latency device resulted in the elimination of video issues, resulting in a downstream throughput increase of 8x.

However, such performance improvements may be eclipsed by the new Wi-Fi 6 standard, which promises data-transfer speeds of up to 9.6 Gbps, far faster than the theoretical 802.11ac speed limit of 1.3Gbps. Further, as more devices are added onto your network, Wi-Fi 6 routers are designed to more effectively manage data requests, ensuring top data speeds are available across each device. Wi-FI 6 achieves this not by through spectrum slicing, but by using multiple user, multiple input, multiple output (MU-MIMO) technology, enabling simultaneous connection with up to 8 devices, as well as the use of orthogonal frequency division multiple access (OFDMA), a technology permitting a single transmission to deliver data to multiple devices at once.

"I would say that what [Edgewater Wireless] is trying to do is great, and will work, but why do it now, knowing that there's new technology and new products on the horizon that will supersede [older WiFi technology]?" asks Andrew Drozd, CEO of ANDRO Computational Solutions LLC, a provider of research, engineering, and technical services related to the electromagnetic spectrum and wireless communications to defense and industrial clients. "If you wait just a little bit longer, I think we're going to have a much better way of [providing Wi-Fi] that will integrate and complement the access points more effectively, and provide more capability and capacity than we've had before."

While Edgewater Wireless' Skafel says its chipsets are cost-competitive with the Wi-Fi 6 chips being developed by Broadcom, Qualcomm, and other vendors, as a new standard, Wi-Fi 6 chips already are being incorporated into new end devices, including TVs, laptops, and smartphones,  smoothing the path to widespread adoption.

"I think when CableLabs and Edge Wireless got together and started developing [Dual Channel Wi-Fi], it made a lot of sense, because at that point in time, people were complaining in the cable company -- 30% of [cable company] trouble calls was simply because their Wi-Fi was so congested," says Joe McCoy, director of technology transition for ANDRO Computational Solutions. "But are the cable companies going to adopt Dual Channel Wi-Fi or not?  With the Wi-Fi 6 being out there, they might choose to wait for it."

Keith Kirkpatrick is principal of 4K Research & Consulting, LLC, based in Lynbrook, NY, USA.


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