OPC defines the communication of real-time plant data between control devices from different manufacturers

1. OPC: The Industrial IoT Protocol That Matters
The foundation of an IoT infrastructure is depends on how well the systems interface with each other
on a plant-wide basis to interchange information safely and constantly. Recent technological
developments, however, address these hurdles to smart factory modification, helping companies get
connected to the cloud to control data and devices, obtain insights and hold machine learning abilities.
OPC (Open Platform Communication) is one of the most broadly used standards for this. We can say
that OPC defines the communication of real-time plant data between control devices from different
manufacturers.
What is Open Platform Communication?
OPC is a series of standards and descriptions for Industrial Automation. It describes a protocol for real-
time transmission with in-plant having various control devices from different manufacturers. OPC which
now used was originally called as Object Linking and Embedding for Process Control, which is depends
on OLE, COM, DCOM technology is planned as a bridge for Windows-based application and process
control hardware.
It is a machine to machine communication protocol for Industrial Automation Industry.
Generally it works as follows:
An OPC server describes a set of variables within a directory tree-like hierarchy creating namespaces.
Each variable has a various data type such as an integer, Boolean, real, string and a default value.
One or many OPC clients attach to the OPC server through a TCP based binary protocol. The clients can
read and write the OPC variables supplied by the server. Clients can also examine OPC variables
for modifications so that you don’t have to survey the variables. In code this is usually done by
submitting a recall function that gets performed when the observed variable changes.

2. OPC Necessity:
Before OPC came into the scenario, each OEM vendor had applications using its own drivers and was
keeping data in complete data paths. This created a group of problems for Manufacturers since every
vendor produced their own data and eventually they were not able to utilize these data for creating
reports. They had to create custom solutions from these various vendors for creating reports. There was
little combination possible since data was locked in an exclusive format. Data were locked in various
PLC model, HMIs, CNC machines, ERPs etc. Also, the plants overlooked the challenge of modify
management whenever a new system was added.
OPC was established as a solution to solve these concerns rather than creating a new product to
regulate technology with no exclusive format and to facilitate general connectivity.
OPC UA:
The current description of OPC is OPC UA (Unified Architecture) by the OPC Foundation. It covers a lot
more functionality than what is reported above. It’s a unified successor to different OPC Classic
descriptions like OPC DA, A&E and HDA. If you want to get started with OPC UA evolution you can use
one of the many client and server SDKs and toolkits for different programming languages. OPC UA is a
standard that allows the open connectivity, interoperability, safety and reliability of industrial
automation devices and systems. OPC UA is generally identified as the essential communication and
data modeling technology for the Industry 4.0 initiative.
It works with various software platforms, is completely scalable and due to its flexibility it has been
universally adopted across various industries.
The OPC UA standard is driven by the OPC base, a non-profit organization with the aim of multi-vendor,
multi-platform, safe and definitive interoperability. Microsoft has a long-lasting partnership with the
OPC Foundation. Connection between has resumed across several essential initiatives, involving support

3. for platform-neutral OPC UA across IoT offerings, including Azure IoT Suite and the common Windows
Platform built into Windows 10 IoT.
Recently, Microsoft presented a .NET Standard mention to the stack to the OPC Foundation GitHub
open-source.
Microsoft is also the cloud vendor that utilizes both OPC UA client-server connections and the new OPC
UA publish-subscribe connections all the way to the cloud and back. Which means Microsoft is in a
typical position to make the rich OPC UA data model, i.e. the semantic representation of the machines,
available in the cloud for allowing services there that so far were only possible on-premises.
OPC UA replaces the OPC Classic protocol, retaining all the usefulness of its predecessor. Because OPC
Classic was constructs upon the Distributed Component Object Model (DCOM), a Microsoft transmission
technology, OPC Classic was jumped to Windows, which became growingly restricting.
OPC UA is fully interoperable across the various operating systems utilized within the plant and on the
factory floor. This is in addition to Windows and industrial technologies like PLCs and includes Linux,
iOS and even mobile operating systems such as Android. Enabling as many devices as possible to
interface helps in the progress of IoT.
OPC and IoT:
The important development in OPC development like OPC Unified Architecture creates it platform
independent, thus enabling it to be embedded into devices & making it complete for the IoT use case.
One of the value concepts of OPC UA (Unified Architecture) is its adaptability from Sensor to Cloud. This
also enables IoT players to model data depend on domain specific like MT connects, BACnet etc.
The data types that can be represented in OPC are categorized as follows:
 Real-time parameter data
 Historical Data
 Alarm and alerts
 Commands
Apart from being a common pool for flowing data to cloud app or a third-party app, OPC is also the
foundation of any SCADA system wherein a modification in a tag value or command activates change in
the status of connected machines.
Cyber attacks
One concern preferred about by IoT is cyber security. Stuxnet worm showed that, PLCs and other
pieces of factory equipment are susceptible to attacks. Due to manufacturing plants were
previously restrict to DCOM, protocols were competing with the difficulty of modern technologies,
developing in a higher chance of attainable faults. As OPC UA is constructed from the ground up
with cyber security in mind, these risks are minimized.
This authorized the attackers to take over the control system, eliminating human-machine
interchange components and, finally, safety settings.

4. Collaboration
Since all ports are closed and the protocol can control generally through virtual private networks
(VPNs), OPC UA works absolutely across domains and workgroups. VPNs enhance security by
enabling a private network to exist within a larger network such as the internet.
As it allows for the collection of data from many sources, OPC UA can help in data analysis, in
addition to minimizing costs for authorizing, staff training, hardware upgrades and system
relocation.
Although previous protocols enabled for industry to progress up to the edge of Industry 4.0, OPC
UA is the more suitable protocol for the Industrial Internet of Things. It acts as the combining agent
and enables for plants to fully execute and acquire the advantage of IoT and Industry 4.0.
OPC and IoT both works behind the scene for customers, the business outcome with these is in the
form of insights into Productivity, OEE and Quality along with platform which allows Data-driven
decisions.