Streamline Messaging and Take the Load Off IoT Sensors


Streamline Messaging and Take the Load off IoT Sensors
Illustration: © IoT For All

A recent industry research report by Juniper Research predicts a near doubling of the Internet of Things (IoT) market, from $31 billion in 2022 to more than $61 billion by 2026. Adoption expectations are high in sectors such as agriculture, smart cities, and manufacturing. Two factors, low-cost connectivity and low-cost devices, underpin these opportunities. These factors characterize the market for constrained devices because limits on memory and processor capabilities keep costs down and encourage mass-market scale.

Efficient data transfer is another element in the low-cost calculus. In the IoT domain, this relies on data transmission protocols, such as CoAP and MQTT. Beyond these protocols, designers are looking at ways to optimize data payloads by only sending essential data, for example. Other strategies involve intelligent ways of transmitting data. This can mean avoiding data communications when values have not changed from one sample to the next. Another approach is to delay transmissions as in the case of non-time-critical communications. Now, it is possible to accumulate sensor readings and send them in an aggregated fashion or at times when communication networks are not congested. To put these ideas into practice, IoT developers and component providers need an agreed way of working for streamlining messages.

Common Service Functions (CSFs) for Standardization

Individual vendors can implement one or more sustainability techniques in their connected device and sensor offerings. However, a standardized, industry-wide approach would be better for many reasons. Standardization allows solution providers to mix and match IoT solution components, which encourages competition and innovation. By fostering common operational practices, standardization encourages a common body of knowledge. This benefits the developer community and promotes reuse over re-invention, which fosters economies of scale and improves affordability.

An obvious place to standardize IoT interactions is via the middleware functionality that IoT platforms typically provide. In architectural terms, the middleware layer sits above a layer that consists of device and communications technologies and below a layer where IoT application logic and visualization dashboards reside. The middleware layer contains a suite of common service functions (CSFs). Device management is one such function. Other functions include location tracking, security, and configurable policies to manage access control. Think of these as standardized tools that developers use repeatedly to build, deploy, and support IoT systems.

In the case of an open standard, the portfolio of tools can grow coherently and transparently over time. This is important to accommodate new requirements that inevitably arise in a fast-evolving sector. Open standardization also allows the widest possible spectrum of industry participants, both large and small, to contribute.

Streamlining IoT Messages for Sustainability

One way to optimize constrained device communications would rely on industry-wide methods for “Communications Management” and “Data Management” functions. Here is how this supports the goal of streamlining the size of messages that IoT devices send without losing information. The two common service functions in the middleware layer would apply a message profile to enrich each message from an IoT device. In effect, they would add supplementary metadata. This would reduce the overhead on devices and networks without sacrificing information that is useful to the apps that consume this data. 

Here’s how the process works. Take the case of a simple IoT system consisting of a constrained IoT sensor device, a middleware IoT platform comprising standardized CSFs, and a dashboard application to display sensor readings. To begin with, the IoT platform is configured with a message profile for the IoT sensor device. This message profile comprises metadata that the IoT platform adds to readings that it receives from the IoT sensor device. The metadata includes a unique identifier and location information for the sensor device. The metadata also includes a descriptive label for the meaning of the data. In the case of a heat sensor, an example label might be temperature.

When the sensor sends a reading, this need only be a numerical value, such as 32. Upon receipt of the reading, common service functions within the IoT platform would then apply a message profile. This would add useful metadata to the reading before dispatching it to the dashboard application. In addition to the numerical value, 32, the enhanced message would include the unique identifier and location of the sensor device. It would also include the temperature label to convey the meaning of the data. Depending on use-case requirements, more complex message profiles are possible.

Combining Service Functions

At scale, this simple arrangement, using two standardized common service functions, illustrates how developers can design systems that manage constrained device capabilities and communications costs. An important IoT sustainability strategy is to streamline the size and frequency of messages without losing information. Standardization helps to reduce the energy and processing overhead when using devices and networks from multiple vendors.