3 Major IIoT Concerns and How to Address Them

Three concerns often surface: security, working with IT and scalability.

• Security is vital. We want to get valuable data out of control systems and equipment without allowing access to those systems.
• IT departments are busy and have other priorities. They’re understandably reluctant to poke holes in firewalls or create special networks for control needs.
• Scalability. We can acquire data from local systems and remote equipment, but IIoT demands vast amounts of data from far-flung sites. How do we scale data acquisition?

Request-response

The standard model for computers communicating on a network is request-response. A client device or software requests data or services and a server computer or software responds by providing the data or service.In automation, a typical client is an HMI on a PC and the server is a programmable logic controller (PLC) or programmable automation controller (PAC) connected to field sensors. The HMI requests data from the controller, and the controller responds.

Publish-subscribe

A different way for devices to communicate on a network is publish-subscribe, or pub-sub. Here, a central source called a broker (or server) receives and distributes all data. Pub-sub clients can publish data to the broker or subscribe to data on the broker, or both.

For IIoT, pub-sub makes sense because it efficiently moves data among several sources and destinations. It also makes sense because its lightweight, single link minimizes difficult client-server connections and works on low-bandwidth, expensive or unreliable networks—like monitoring remote equipment.

Pub-sub with MQTT and Sparkplug

The pub-sub transport protocol MQTT (http://www.mqtt.org) is an OASIS standard and an ISO standard with an industrial history. It was invented in 1999 for an oil and gas pipeline application to reduce expensive communications via satellite lines.

To industrialize MQTT further, Cirrus Link Solutions released the Sparkplug spec in 2016 (http://www.cirrus-link.com/oem-device-data-integration). Sparkplug added binary encapsulation, device state and topic definition to make MQTT easier to implement and more suited to critical applications.

• Compressed payloads and stateful communications for remote devices with irregular connections.
• Automatic reconnection and data transport for offline devices.
• An important security advantage: outbound connections from clients to the broker.

[Editors note check out our Startups Directory for Startups in this space. See IoT Startups Directory 

for example Bevywise Networks and Infinity Think among others ]