Connectivity Framework 1 : Introduction
1.1 PURPOSE
The IIoT landscape is replete with proprietary connectivity technologies and specialized connectivity standards optimized for a narrow set of domain-specific use cases in vertically integrated systems . These domain-specific connectivity technologies , though optimal in their respective domains , can be a hindrance to the sharing of data , designs , architectures , and communications essential to creating new value streams and unlocking the potential of a global IIoT marketplace . The overarching goal of IIoT connectivity is to unlock data in these isolated systems (“ silos ”) and enable data sharing and interoperability between previously closed components and subsystems ( brownfield ) and new applications ( greenfield ), within and across industries .
This document maps the rich landscape of IIoT connectivity . It clarifies the IIoT connectivity stack , defines an open connectivity reference architecture , and helps practitioners navigate their way to categorize , evaluate , and determine the suitability of a connectivity technology for the system at hand . Specifically , it addresses the following questions :
• What connectivity layers to expect for IIoT ?
• What core functions to expect from each layer ?
• What are the typical considerations and trade-offs at each layer ?
• How to open up communication to participants using a domain-specific connectivity technology ?
• What is expected from core connectivity standards ?
• How to categorize a given connectivity technology ?
• How to evaluate a given connectivity technology ?
• How to determine suitability of a connectivity technology against system requirements ?
• How to determine the most appropriate core connectivity standard ?
• What are the most suitable core connectivity standards for a particular ( sub ) system ?
1.2 SCOPE
The interoperability layers of an IIoT system are hourglass shaped . The top is a wide spectrum of data models and functions specific to a particular industry and the “ neck ” is the “ internet ” network layer common across industries , as shown in Figure 1-2 . Connectivity provides the basic data-sharing mechanisms to support the higher-level functions such as Distributed Data Interoperability and Management as a crosscutting function ( semantic interoperability , see Industrial Internet Reference Architecture 1 ).
The neck of the hourglass in Figure 1-2 is the starting point — it is the “ internet ” in “ IIoT ”. But the connectivity layers above the neck are not well understood , so we focus on the connectivity functions and considerations above the “ internet ” networking layer for building IIoT systems .
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See [ IIC-IIRA2015 ] IIC : PUB : G5 : V1.0 : PB : 20170228 - 9 -