Choosing an IoT protocol can sometimes feel like a win-lose situation. Pick a network that supports high-bandwidth applications for, say, browsing the Internet or streaming HD video, and you’re faced with high-power consumption and short-distance connectivity. Or, you can go with a network that enables a long-range connection and low-power consumption, but only supports low-bandwidth devices.
In recent weeks, however, new IoT protocols have opened possibilities for coverage and memory. Here are some ways that companies are making the most of existing protocols, forging new long-distance networks, or expanding communication protocols for non-volatile memory devices.
Combined Wi-Fi and LoRaWAN Signals Broaden IoT Applications
While Wi-Fi supports devices in places “where people are” and LoRaWAN exists “where people usually are not,” the combination of the two wireless protocols enables long-distance connectivity and better bandwidth support for IoT applications.
A recent white paper from the Wireless Broadband Alliance (WBA) and the Long Range Wide Area Network (LoRaWAN) Alliance suggests that LoRaWAN can be added on top of an existing Wi-Fi network to better support IoT in homes, smart buildings, smart cities, smart revenues, and smart transportation.
LoRaWAN can be deployed alongside a Wi-Fi infrastructure as a plug-in on Access Points (AP) or in customer premise equipment, like a home hub or a set-up box.
The authors of the white paper make important distinctions between Wi-Fi and LoRaWAN and point out how the tandem rollout of both networks can cut operation costs and increase efficiency. While Wi-Fi supports the high bandwidth of critical IoT for device-to-device communication, its medium-range connectivity, high data rates, and high power consumption limit applications. In contrast, LoRaWAN offers long-distance connections for massive IoT devices with low-bandwidths—like smart home sensors—without sapping battery life.
The white paper distinguishes the differences between massive IoT and critical IoT. Image used courtesy of WBA and the LoRaWAN Alliance
The paper offers dozens of examples of how combined Wi-Fi and LoRaWAN protocols could enhance IoT functionality in residential, commercial, and public spaces. When describing the benefits of hybrid Wi-Fi and LoRaWAN use in smart building/smart hospitality, the authors cite Nomosense, a company that has tapped into LoRaWAN sensors and Wi-Fi hotspots to secure remote construction sites that lack cellular network coverage.
If a sensor indicates alarm, a Wi-Fi hotspot can mobilize a local workforce to assess the site for hazards, ensuring the safety of staff. In this way, Nomosense has designed a solution that leverages Wi-Fi hot spots to “both provide location services and back-haul to LoRaWAN Gateways.”
Wi-Fi and LoRaWAN location services. Image used courtesy of WBA and the LoRaWAN Alliance
Authors of the collaborative initiative posit that merging both wireless protocols will support a 5G future.
Amazon Sidewalk Sends Data Up to a Mile
At the Amazon Devices Event in September, Amazon announced its own protocol, Sidewalk, a low-bandwidth network that sends data further than Bluetooth and Wi-Fi without draining power from IoT devices. Using a 900 Mhz frequency band, the wireless protocol supports connections up to a mile from a hub. Amazon also claims that Sidewalk will address another troublesome element of IoT—software syncing—with “secure, over-the-air updates.”
The company cited several ways the long-range network can be applied to their own IoT devices, including Ring smart lighting and Ring Fetch, a new dog-tracking device that alerts owners when their dog has left a set perimeter.
Amazon’s Ring Fetch can operate on Sidewalk, which sends data up to a mile from a hub. Image by Amazon
Amazon’s device chief Dave Limp encouraged developers to consider other IoT possibilities with Sidewalk, including connection to “weather stations to tell you how much rain you’ve gotten, a water sensor in your garden with your tomatoes, [or] a little sensor in your mailbox that lets you know when the mail has been delivered.”
Sidewalk is designed with wireless mesh networking in mind: more devices connected to the network means more Sidewalk coverage over a greater area. To test this network range, Amazon sent devices to 700 of its employees, family members, and friends living in the LA Basin. Within three weeks, the entire city of Los Angeles upheld Sidewalk connectivity.
As with any IoT wireless protocol, Sidewalk also raises questions about security. Forrester analyst Jeff Pollard commented on the security of Sidewalk, observing that “If use cases like home automation or IoT devices make use of [Sidewalk] technology, they generate telemetry data. Connected devices—especially in the home—give vast amounts of information about your behaviors and activities, which could also go to Amazon with this connectivity."
Amazon plans to publish the wireless protocol, so other device makers can connect to Sidewalk as well.
Adesto and Cadence Expand xSPI for Non-Volatile Memory Devices
Like security, memory is another pressing concern for IoT developers. Because many IoT systems must uphold local AI functions and operate code-heavy wireless stacks, manufacturers are ever-striving to enable higher transfer rates and lower latency for flash memory. Adesto Technologies Corporation and Cadence Design Systems are responding to the call for more local storage by expanding the ecosystem around xSPI.
Like SPI, xSPI (Expanded Serial Peripheral Interface) communication protocol is a master interface, developed by JEDEC, for non-volatile memory (NVM) devices. With low signal count and high data transfer bandwidth, xSPI can access multiple sources of compatible slave devices. The interface can also verify the device under test (DUT) using a comprehensive test suite.
Example of a system-level block diagram. Image by Cadence
Adesto and Cadence have rolled out three new products—Cadence Memory Model for xSPI, Cadence Host Controller IP for xSPI, and Adesto’s EcoXiP™ octal xSPI—to boost transfer rates and lower latency in IoT devices.
Cadence Memory Model for xSPI, the first commercially-available model of its kind, ensures that users can easily use octal NOR flash with the host processor in an xSPI system. The Cadence Host Controller IP for xSPI allows for XiP, supports multiple SPI protocols within a single IP, and upholds maximum octal SPI data rates. It also simplifies SoC timing with a soft storage combo physical layer (PHY) IP.
With Adesto’s EcoXiP, users can save power and increase performance (compared to quad SPI devices) without expensive on-chip embedded flash.
Adesto’s EcoXiP™ octal NOR flash. Image used courtesy of BusinessWire
A press release explains that “Expanding the flash SPI accesses from the traditional four I/Os (quad SPI) to eight I/Os (octal SPI) with the xSPI serial synchronous protocol increases the serial NOR flash throughput and provides a more efficient solution for emerging applications.”
Adesto’s CTO Gideon Intrater remarked, “Moving intelligence to the edge can provide significant advantages, but heavier local processing means that architects must revisit their system’s memory architecture.”
Although memory may need to be updated for more local storage, Adesto and Cadence are confident that their products will save power and cost while enhancing performance in IoT devices.
Each of these wireless protocols—the combination of Wi-Fi and LoRaWAN, Amazon Sidewalk, and the expansion of the SPI ecosystem for NVM devices—accounts for the demand for more flexible IoT applications. As designers continue to push the limits of local memory and range, network options will likely broaden as well.
Which wireless protocols are productive for your work? Let us know in the comments.