The success of the internet is largely due to a set of standards which define the internet protocol (IP). Prior to IP, communication systems required their own domains, each with unique protocols and infrastructure.
The key advantage of IP is that it acts as a foundation for multiple communication systems to interoperate over the same domain.
Many of the current systems of automation and control reside on proprietary domains which do not use IP. The installed base of such proprietary domains is often extensive and cannot easily be replaced. Such systems may be connected to the internet, but a gateway and (often bespoke) control software are needed to interface with IP-based IT infrastructure.
However, data from proprietary protocols can be carried over IP-based IT infrastructure, if a suitable framework can be devised. This would allow the existing installed base of proprietary domains to communicate seamlessly with newly installed infrastructure based on IP connectivity.
The advantage is that the information from existing domains can easily be shared between and through public internet infrastructure to trusted cloud servers.
The ability to make such devices become accessible over the internet is known as the Internet of Things (IoT). Implementing effective IoT solutions often requires a more multidisciplinary approach, including the following considerations:
- An understanding that IoT security is systemic
- An awareness that interoperability is critical
- A systematic approach to testing
- A thorough cost/benefit analysis
- Comprehensive documentation
- An understanding of performance benefits
Open Connectivity Foundation (OCF) is a standardisation organisation specifying a set of technologies designed to make such IoT systems a reality. The aim is to provide a framework for carrying data from existing automation domains over IP, while providing device discovery, on-boarding, resource discovery, and control in a highly secure manner.
The specification is IP-based, and is built upon a large set of international standards defined by the Internet Engineering Task Force (IETF) for a sound technical basis. The concept behind the OCF architecture is that application usage of the underlying software stack should be simple.
This is enabled by leveraging the representational state transfer (REST) model; the simplicity of which enabled mass adoption of Web services and is well known by today’s application developers. To make the stack more suitable for small devices, the HTTP is replaced by its binary variant CoAP, and the JSON data is compressed in CBOR to achieve smaller data transfers. All data transfers are secured by industry standard datagram transport layer security (DTLS).
The OCF specification can be used in various deployment scenarios, for example:
- Communication between peers on the local (proximal) network
- Communication between devices on the proximal network and cloud entities
- Communication between cloud entities
By providing true IoT interoperability and world-class security, OCF allows for the best mix of wired/wireless connectivity solutions to be chosen for the desired application, while enabling automation decisions to be made based on information from multiple domains.
Such decision-making can now utilise a mix of local and/or cloud-based computing and analytics (such as Artificial Intelligence) to improve the efficiency with which we use our infrastructure.
This allows operators to both cut costs and to develop new revenue streams through business model innovation and without being hampered by the lead time and development cost of the secure communication framework.
A longer, more detailed version of this article is available online under the same heading. Visit www.smart-energy.com