IIC Journal of Innovation | Page 22

Architecting the Smart Grid Using the Industrial Internet of Things model, communication pattern, and quality of service (QoS) parameters like reliability, data rate, or timing deadlines. While connecting two systems is a challenge, it is solvable with a specialpurpose “bridge”. Nevertheless, it does not scale; connecting N systems together requires Nsquared bridges. As N gets large, connecting them all becomes untenable. One way to try to solve this “n-squared” problem is to dictate the standards to use in each of these areas (protocol, data model, communication pattern, etc.) This is the approach taken by Industrie 4.0. The issue with this approach is that it is impossible to cover all system types and needs in a single standards stack. Industrie 4.0 addresses this in its focus on manufacturing. The IIC’s ambition is to address multiple industries. At the other end of the spectrum are specialized bridge points like “Enterprise Service Buses” (ESB). ESB’s like Apache Camel use the word “bus,” but they are fundamentally not a distributed concept. Instead, they provide bridging between multiple connectivity frameworks, so all systems have to connect to the ESB and translate to its core connectivity bus. Currently, ESBs are focused on enterprise software system integration and are generally implemented as a central service. Most are not open standards or architectures either. The IIRA takes an intermediate approach to provide a “Core Connectivity Standard”. Unlike an ESB, the core connectivity is itself a connection standard to which devices and applications attach. Other devices and applications connect through “gateways”. The core standard then connects them all together. This allows multiple protocols to co-exist, without having to bridge between all possible pairs. Each needs only one bridge to the core (See Figure 2). Figure 2. The Connectivity Framework in the IIC’s Industrial Internet Reference Architecture calls for a core standard connectivity bus with gateways to bridge to existing devices and protocols streamlining interoperability and security. IIC Journal of Innovation - 21 -