Forbes Column

May 10, 2021
Amazon’s Sidewalk Unmasks Hidden Value of Mesh Networks

By Bob O'Donnell

The benefits of having devices that are nearly always connected has never been more obvious than it is today. In that regard, cellular networks and technologies like 5G have proven to be incredibly valuable.

At the same time, there’s no denying that integrating cellular connectivity into every connected device we own isn’t a reasonable option for both practical and economic reasons. It’s simply too expensive and too challenging to do that. Various flavors of WiFi and even Bluetooth, of course, have also become an essential part of the connectivity fabric and are a great solution for many devices and applications.

The problem with these technologies is that their range isn’t very far, particularly when you move from inside to outside. What many applications could really use is a technology with a range closer to cellular, but with costs that are at the same level or even cheaper than WiFi.

As luck would have it, some of those types of technologies do exist, but not necessarily in the places you expect. A chip company called Semtech has a proprietary technology called LoRa (short for Long Range) that’s been used in industrial and other types of low bandwidth IoT applications for over 6 years now. LoRa doesn’t have anywhere near the throughput of WiFi or even Bluetooth. It typically handles data streams measured in 10s of kbits per second vs. 100s of kbits per second for Bluetooth Low Energy (LE) and single digit Mbits per second for regular Bluetooth. However, it can reach as far as 30 miles in rural environments. In addition, because it uses frequencies below one GHz (915 MHz in the US and Canada and other sub-GHz frequencies in other parts of the world), LoRa signals can also easily pass through walls and buildings in dense urban environments.

Believe it or not, another interesting long-range technology called 900 MHz FSK (frequency shift keying) leverages some of the same core capabilities as 1990s era 900 MHz cordless telephones. While it doesn’t have the same range as LoRa, the technology is well suited for smart home applications and can communicate with some legacy home appliances.

To make these various long-range low-cost connectivity technologies truly useful, however, requires a mechanism for connecting them all together in a mesh-like fabric and providing a standardized means of communicating over them. In essence, that’s what Amazon’s Sidewalk network and protocol provides. First unveiled in September of 2019 but expected to become fully active next month, Sidewalk uses a combination of three different physical connection types: a version of the aforementioned LoRa, 900 MHz FSK and Bluetooth LE—and then overlays a platform and standardized mechanism for secure communications across these connections. In the process, it can turn potentially millions of separate devices into an ad-hoc network that’s likely to have a range not much different than cellular networks.

As amazing as that sounds—and in many ways, is—Sidewalk is most certainly not a full-blown alternative to cellular networks. As mentioned, it’s only intended for very light data applications with a maximum throughput of 80 kbps—that’s not even good enough for a low-quality MP3 audio stream. For IoT and smart home applications that only send small updates like “the light is on” or “the door is unlocked,” however, it’s more than adequate.

Plus, thanks to the company’s recent announcement with Tile, it provides a very competitive alternative to Apple’s AirTags. Though it’s based on a different set of technologies, Apple’s Find My network that powers AirTags (and other Apple “finding” features) offers a conceptually similar mesh network model that leverages the huge installed base of Apple devices to help locate a lost AirTag. As with the Tile and Sidewalk combination, the way AirTags work is that they sent out brief messages requesting the location of a lost object connected to the tag and then that message gets passed along from device to device (unbeknownst to the people’s devices who are part of the tag chain) until the item is discovered and its location is sent back.

In Apple’s case, it can leverage most of the billion+ installed base of iOS devices to essentially hop from one device to another using a combination of cellular, WiFi, Bluetooth and UWB (Ultra Wideband—a short range radio technology that operates in the GHz range) connections to get where it needs to go. Before the Amazon partnership, Tile was limited to using only an ad-hoc network of other Tile devices. However, as of mid-June most all of the Amazon Echos and Ring Cameras sold since around the middle of 2019—likely to number in the hundreds of millions—will suddenly become part of the Sidewalk network, instantly catapulting it into significant competition with Apple. Of course, Apple’s shared mesh network is a constantly evolving, primarily mobile driven one built around the current location of participating iOS devices. Amazon’s Sidewalk, on the other hand, will essentially be a fixed network based on the plugged in devices that enable it, but it will certainly be interesting to see how they end up comparing.

As cool as these technologies are, they don’t come without some degree of controversy. Both Sidewalk and Apple’s Find My are opt-out technologies, meaning they’re turned on (or will be turned on) by default. Anyone who owns these devices can choose to turn them off—though you’ll have to dig through several layers of menus to do so—if they don’t want their devices to be used as part of these shared mesh networks. However, both companies are hoping and expecting that the potential extra value that these kinds of networks can provide (frankly, as well as most people’s complacency when it comes to actually changing these kinds of things) will lead people to just leave them on. In Apple’s case, I think that’s probably true, but it will be interesting to see how Amazon Echo and Ring camera owners react, particularly if they don’t own Tile devices.

Of course, Amazon does have the advantage that Sidewalk can potentially be used for more than just finding devices. As part of the company’s announcement last week, they unveiled an application with a company called CareBand that creates wearable technology designed to track people with dementia. In addition, there’s the potential to use Sidewalk to make the process of setting up or resetting smart home appliances easier, particularly if home WiFi is down. Amazon also announced a partnership with Level to remotely control Level’s smart home locks even when homeowners are outside the Bluetooth range of those locks. This is a classic example of a cellular-like connectivity benefit without the need for cellular. It also hints at the enormous range of other applications that could be built to sit on a free, ubiquitous, wide area network—albeit one with limited bandwidth. In fact, it’s going to be fascinating to see exactly how Amazon and others attempt to leverage the Sidewalk network.

For these efforts to succeed in a big way, however, Amazon is going to have address the potential opt-out concerns, as well as the fact that to make these type of shared mesh networks work, you essentially have to let your neighbors “share” a bit of your bandwidth, which not everyone may like. That, in turn, can trigger potential privacy and security concerns. However, the company is quick to point out the extensive steps it has taken, including data encryption and a multi-layer protocol stack, to specifically avoid potential issues here.

Ultimately, mesh networks like Sidewalk are likely to be significant new enablers for a wide range of products and services, only a glimpse of which are starting to be revealed. Without a doubt, this will be a very interesting space to watch.

Disclosure: TECHnalysis Research is a tech industry market research and consulting firm and, like all companies in that field, works with many technology vendors as clients, some of whom may be listed in this article.

Here’s a link to the original column: https://www.forbes.com/sites/bobodonnell/2021/05/10/amazons-sidewalk-unmasks-hidden-value-of-mesh-networks/

Forbes columnist Bob O'Donnell is the president and chief analyst of TECHnalysis Research, a market research and consulting firm that provides strategic consulting and market research services to the technology industry and professional financial community.