Connecting machines and other systems over cellular networks, however, has the advantage of the basic infrastructure being already in place and it offers a convenient and secure means of connecting items to the Internet and to the cloud for remote control, data collection and analysis. Bluetooth and Wi-Fi can be used to establish a local area connection to a hub or router, from where data can be conveyed into the cellular network.
Currently, 2G and 3G networks are used predominantly for M2M, but as the number of connections increases and network capacity starts to become an issue, migration to 4G networks is set to accelerate, with 3G being used as a fallback technology where adequate LTE coverage is not available.
Systems everywhere are becoming smarter, and in many cases data is already being collected within a controller but is often not being communicated elsewhere or being used effectively. However, this is now readily achievable – with a cellular M2M module connected into a PC, for example, this data can be sent into the cloud. Such an operation carries tangible financial and environmental benefits, for example in factory automation, where there may be a lot of moving parts that have to be serviced and the data can be used to determine exactly when servicing or adjustment becomes necessary and what parameters need to be reset.
One particular application that is suited to this approach is retrofitting communications modules to existing heating, ventilation and air conditioning (HVAC) systems to improve environmental control. This has been described in detail in an Intel case study, which details a collaboration with Wind River and McAfee. This enabled it to apply intelligent gateway solutions to help a leading HVAC vendor to connect its units efficiently to the cloud in order to aggregate, filter and share data securely. These intelligent gateways simplify access to the data in the HVAC embedded systems and allow them to connect to intelligent infrastructures, enabling proactive management of a unit's performance and providing early warning of potential HVAC issues. They also offer the capability for remote diagnostics, monitoring and control, advanced energy management and third party content integration.
Intelligent gateways are also being used to connect legacy systems and new devices to the cloud, with automotive electronics being one of the first areas where this is being applied. Mobile health, fitness and the care of the elderly are all further areas where the connection of appropriate sensors to the cloud is likely to revolutionise people's lives.
A study published in 2014 by Vodafone found that 22% of organisations already had at least one M2M system in place, with a further 42% expecting to do so within the next two years. The main reasons for M2M adoption within sectors varies considerably: in energy, the main driver is the cost savings that can be achieved by automation; in manufacturing, it is the opportunity to improve process and productivity that provides the impetus. All the sectors surveyed cited the opportunity for innovation as one of their top three triggers, but for retail, transport and logistics it was the main one.
In terms of cellular standards, there is expected to be a steady move towards newer generations of technology. Even where 2G data rates would be adequate, it is predicted that 3G and 4G modules will overtake them as economies of scale start to make the modules price competitive and this move will be accelerated by the demise of the 2G networks.
The recent introduction of the LTE Cat-0 variant to Release 12 of the 3GPP Long Term Evolution (LTE) standard developed specifically for Machine Type Communications (MTC) – the 3GPP's generic term for M2M – will smooth the path towards the adoption of 4G for these applications in the longer term. 3GPP Release 13 will further introduce a specific variant called LTE MTC.
Using an established cellular network gives assurance of reliability, already proven across millions of phone connections, as well as built-in security features that are trusted by governments and the relevant regulatory bodies. Quality of Service is also managed by the operators to levels far in excess of those essential for M2M, in order to optimise user experience and minimise churn.
As unit volumes start to increase, it is anticipated that prices will drop and this, in turn, will help drive demand. It has been estimated that module costs need to fall to around 25% of their current value to enable the full market potential to be realised and this is expected to happen over the next two to three years. Some of the cost reduction can be achieved by simplifying the modules, since M2M does not require the complex functionality demanded by a smartphone. Seamless interoperability of Bluetooth, 801.11, 3G and LTE connectivity will also be important in realising this potential.
Choosing a M2M module
What should a designer look for when choosing a module for a new M2M application? Appropriate certification is a must and modules that support a number of different mobile operators allow the option of changing networks at a future date, as well as minimising inventory if the same system is to be used in more than one country.
With the decommissioning process for 2G networks already starting, it is advisable to specify 3G (HSPA/HSPA+) modules or dual standard 3G/4G modules, as this provides a degree of future proofing. As 4G (LTE/LTE-A) networks mature over the next few years, the deployment of 4G modules will steadily become competitive with the older technologies and will offer the opportunity of faster data rates for relaying more complex information including video, as well as providing higher capacity for the growing number of connections.
In addition to network compatibility, further key considerations include:
* sata rates
* size and form factor
* power consumption
* high levels of integration
* interfaces to other technologies
* 'plug and play' functionality
The support that is ideally required includes a strong ecosystem, which can provide the system integrator and the end user with a channel to receive optimum service and competitive tariffs from the network operator.
Laurence Dellicott is technical director with Silica