Due to the distributed nature of IoT, connectivity/networking is perhaps the most critical element of the full IoT stack. It is also the area that requires the greatest consideration of sensitivities and trade-offs regarding the requirements of the use cases, the nature of their deployments, and the capabilities of the technologies being used.
There is enormous diversity in how IoT is deployed and this has the greatest implications for connectivity choices. In this article, based on the July Position Paper ‘Connected-by-Design: Optimising Device-to-Cloud Connectivity’ (sponsored by Eseye), Transforma Insights examines the nine key sensitivities that need to be considered when making decisions over IoT connectivity.
1 | Cost
This is always going to be a consideration and a limitation on what a developer can do with an IoT device. There are almost no applications that are completely price insensitive, meaning there is always an incentive to keep prices low. The link between price reduction and adoption is not linear; a halving of the cost of putting a device into the field, whether that be connectivity or hardware costs, will likely mean much more than double the sales.
As an example, disposable devices (which Transforma Insights includes in its TAM Connected Devices IoT Forecasts) might be viable at a high price point for tracking high value assets such as pharmaceuticals or precious metals, but the volumes of those devices will be tiny. Cut the price by 90 percent and it becomes viable for millions of much lower value assets. Cut it by 99 percent and the sky’s the limit.
2 | Power
Power, and specifically the access to mains power, is a key determinant of how an IoT application is architected. The use of battery power necessitates numerous compromises in terms of connectivity technology used, communications protocols, processing, and more. All of those choices have implications for the power usage and require some sort of trade off.
According to Transforma Insights’ Case Study database, which analyses real world IoT deployments, over one-quarter of enterprise IoT deployments today are reliant on battery power, and with the increasing prevalence of LPWA technologies, the ability of enterprises to deploy applications where there is no mains power will only increase. By 2030 it is easily possible that 50 percent of enterprise IoT deployments will be heavily or exclusively based on battery-powered devices.
3 | Speed
The requirement for high-speed connectivity will be largely determined by the type of use case. The variation is very wide, from ‘trigger’ use cases that require only to send a small packet of data perhaps once in a lifetime, through to video-based use cases, such as CCTV, that may need to transmit a constant stream of rich data. Performing some processing on the device can reduce the demand for high bandwidth connectivity.
4 | Latency
For some use cases, the key thing will not necessarily be the volume of data to be sent, but the round-trip time of the interaction between the IoT device and the server. Industrial automation processes or autonomous vehicles, for instance, may require a very low latency. Reducing latency is one of the key motivations for implementing some form of edge computing, moving the processing closer to the IoT device, rather than requiring communication to a central server which could be many hundreds of kilometres away.
Some protocols are better for reducing latency, for instance those that do not require complex handshakes between client and server. UDP, for instance, supports lower latency than TCP.
5 | Availability
Where the device is located is a constraint when it limits access to specific networks (and power) and/or the ability of people to access the device. Geographically remote devices may have very limited options of how to be connected, often being limited to technologies that are low bandwidth or costly, or both. This might create a strong impetus for increasing processing on the device, using machine learning to automate local decision making.
This helps to minimise what traffic needs to be sent. This limitation also has strong implications for, for instance, which networking protocols might be used, favouring less chatty ones such as MQTT-SN. Furthermore, being in a remote location can also limit the ability of people to make changes to the device manually (necessitating remote management).
6 | Mobility
Some IoT use cases are mobile, whereas others are static. This has implications for the choice of technology. For instance, a connected vehicle requires a cellular technology capable of handing over between cells at high speed. Static devices, in contrast, may need a technology with superior propagation characteristics to ensure coverage within a building or in a remote location.
7 | Durability
Turning predominantly to the hardware aspect, some IoT deployments will require ruggedised devices, potentially able to withstand extremes of temperature and vibration. This will have some implications for other connectivity-related choices. For instance, more ruggedised devices will often favour MFF2 soldered SIMs, or iSIMs, rather than removable SIM cards, with potential implications for how connectivity is delivered.
8 | Space
This relates to the dimensions of the device and the inherent limitations that come from that. A monitoring device attached to a piece of industrial equipment can probably be of any size, within reason (although will probably need some consideration of ruggedisation to cope with vibrations, dust, heat and cold).
A smart watch, in contrast, has a very strict set of dimensions it needs to keep to. This has implications particularly for trading off against other factors, such as price: smaller components tend to be more expensive. For instance, the use of eSIM or iSIM can significantly reduce the space requirements for cellular connectivity.
9 | Security
Some use cases have a greater inherent requirement for security than others, for instance those involving the taking of payments (e.g. payment terminals or ticket machines), those that handle potentially personal or household data (e.g. smart metering), those where there is a risk to life (e.g. connected heart rate monitors) or those relating to critical national infrastructure (e.g. smart grid).
However, this does not mean that mundane use cases do not also require a decent level of security; the example of the Las Vegas casino whose core systems were hacked via a man-in-the-middle attack via a connected fish tank is testament to that. There are many layers to security, from hardening of end points to prevent tampering, through to the application of robust transport layer security, for instance using the new IoT SAFE standard.
There is a further set of constraints which are much less use case specific, which also need to be included in considerations of trade-offs between the various elements of a proposition:
10 | Compliance
As IoT has matured, a variety of relevant regulations have been introduced around the world. They include the likes of permanent roaming, data sovereignty, and newly established rules around IoT device security. This plethora of new regulations with wide variations between countries, creates an increasingly complex environment in which keeping tabs on all of the possible regulatory issues is challenging.
11 | Commercial
Every IoT deployment uses products and services procured from third parties, whether it be cloud hosting, systems integration, or cellular connectivity. Different providers will be able to support in different ways and in some cases the proposition may not exactly align with the optimum configuration for the use case. Some aspects of the functionality outlined in the bullets above may need to be compromised to reflect the reality of the commercial propositions available on the market.
12 | Sustainability
Environmental considerations are increasingly important for enterprises, particularly in IoT deployments which are often specifically implemented in order to help meet Sustainable Development Goals (SDGs). Considerations of power consumption or e-waste may influence a particular approach to an IoT deployment. Decisions around how IoT is deployed will involve consideration of each of these constraints, and more importantly the inter-relationship and trade-offs between them.
For instance, devices that need to rely on low bandwidth networks may need additional capabilities for pre-processing the data on-device. Similarly, with unlimited funds most of the other challenges can be resolved, for instance through very small components or the use of expensive network technologies. Some of these may need to be compromised when deciding on the best combination of technologies and device specifications to use.
About the report
This article is based on the recently published free Transition Topic Position Paper ‘Connected-by-Design: Optimising Device-to-Cloud Connectivity’ from Transforma Insights, sponsored by Eseye. The report examines the transition occurring in the way Internet of Things solutions are developed. The IoT is moving from a one-size-fits-all approach built on technologies that were not developed with the constraints of IoT in mind, to a ‘Connected-by-Design’; approach, reflecting the unique requirements of each IoT use case, complexity of the mix of components, and where careful consideration is given to how all the elements are optimised, particularly connectivity.
