A lot of information and questions have been swirling through the industrial automation community over the past year or two regarding SCADA (Supervisory Control And Data Acquisition) and the cloud. The din of voices from seasoned users, visonary cloud proponents and industry gurus has made it difficult sometimes to distinguish between true benefits, realistic options, inflated hype, and ominous warnings. Some vendors, who are apparently more concerned about their slice of the SCADA market than helping the conversation, are adding a dash of FUD (fear, uncertaintly, and doubt) into the mix. Before holding any serious discussion, we’d like to address these issues.
FUD: Putting a SCADA system in the cloud is risky and unwise.
Fact: Agreed. Don’t do it. Instead, use the cloud to enhance a SCADA system.
Let’s start by eliminating the main FUD factor right from the get-go. Nobody expects to plop a SCADA system on the cloud and have it perform as well as running it in-house. The technology is still evolving. What is possible right now is to extend or enhance a SCADA system by connecting it to a real-time cloud system. Here is how the concept of SCADA enhanced by the cloud cuts through the typical FUD:
Performance
FUD: SCADA in the cloud will impact your system performance.
Fact: Cloud-enhanced SCADA keeps primary control in the plant with zero impact on system performance, while any connection to the cloud should meet the core requirements for real-time cloud for performance.
FUD: SCADA in the cloud will have speed and latency issues.
Fact: Cloud-enhanced SCADA systems can support high data rates and low latency.
FUD: SCADA in the cloud means long polling cycles.
Fact: Cloud-enhanced SCADA can be implemented on a publish/subscribe, event-driven basis, with no polling necessary.
FUD: SCADA in the cloud would require several layers of protocol conversion, resulting in poor performance.
Fact: Cloud-enhanced SCADA can be implemented using a data-centric infrastructure, eliminating the need for protocol conversion until the data arrives at its destination.
Security
FUD: SCADA in the cloud exposes your process to hackers and spies.
Fact: Cloud-enhanced SCADA keeps your process running safely in the plant, behind closed firewalls.
FUD: Cloud hosts are more vulnerable to being hacked than in-house systems.
Fact: Cloud hosts typically invest far more in security than most manufacturing companies.
FUD: SCADA in the cloud exposes sensitive data on a public network.
Fact: Cloud-enhanced SCADA should allow you to select which data points you send to the cloud and protect them with encryption and access control restrictions, if necessary.
Reliability
FUD: SCADA in the cloud means that a connection failure equals system failure and costly plant downtime.
Fact: Cloud-enhanced SCADA means that a connection failure causes momentary loss of non-essential remote HMI interfaces. The primary control system continues to run, because it is completely independent of the cloud system.
FUD: SCADA in the cloud is vulnerable to hosting service outages.
Fact: Many hosting services support 99.9% and better up-time. In addition, a properly designed cloud-enhanced SCADA system can provide fully redundant data paths from inside the plant firewall to inside the client firewall.
These are a few examples of how to clear up any fear or doubt, using the approach of enhancing SCADA with cloud computing. From this perspective we can now hold a more meaningful conversation. Next week we’ll consider some of the more practical questions: What does cloud-enhanced SCADA look like? What can it do for me? How can I use it to get the most out of my real-time data?
