Control System Change Management, Security: Questions and Answers
Invensys and MDT Software provide answers on documenting software changes and security.
Q: How are customers handling HMI change management?
A: Alynn Burk, product marketing manager for Invensys Operations Management: Some customers use a manual process to manage program changes. For example, when a change is made the engineer will save the new program to a main backup file, or a server will be configured to back up all devices on a scheduled basis. This has the advantage of being very inexpensive, plus it is not device specific so it can be used plant-wide. The disadvantages are that human error could prevent the program from being properly saved, there is no archive of prior revisions of the program, and there is no documentation on what change was made or why. Alternatively, some controls vendors offer basic version control within their packages. These packages are also limited in that only selected systems are backed up, or provide a very limited solution for other device types.
Most manufacturers, especially in a multiplatform environment, have found neither of these change management solutions meets their needs. These customers use an automation change management system (CMS) to provide a centralized archive of all current and prior program versions, change detection and notification, change documentation, and secured access. Our customers have asked for an automation change management solution to support the editing, archiving, and deployment of our products. That is why we have partnered with MDT Software, the creators of AutoSave and AutoSave for System Platform, to provide automated advanced change management and version control for Wonderware InTouch and System Platform. Uniting these HMI systems with a change management system creates a protected and secure automation environment for controlling plant operations.
Q: How does change management software function?
A: Matt Lawson, director of technical operations, MDT Software: Our AutoSave change management system protects against the loss of program data and code changes to minimize downtime and safety risks while increasing productivity and regulatory compliance. By capturing changes as they are made and archiving them, the ability to restore a prior version after an equipment failure or other event is a single click away. In maintaining a history of revisions, two versions of an object can be compared to review changes, thus providing greater insight and protection of plant assets and personnel.
Q: How are your customers addressing HMI security?
A: Burk: Due to the recent Stuxnet virus, cyber-security has become a principal concern for industrial plants. While Stuxnet targeted PLCs, the same techniques could have been used to introduce threats at the HMI layer. Proper use of firewalls, anti-virus software, and malware scanners is recommended to help prevent infection. However, as Stuxnet has proven, new threats emerge that can bypass these protections until a fix is released. The best protection is gained by managing all programs in a central, secure location that employs technologies that can scan the control system and HMI program details and the programming software itself, looking for abnormal changes. Many Invensys customers use an automation change management package designed to identify and manage changes at the automation layer. Wonderware has endorsed the change management solution from MDT Software to address this issue by exposing and quickly identifying any unauthorized changes. Typically these change management packages store changes separately, which limits the spread of any infection and allows the user to restore uninfected copies.
Q: What’s most overlooked on this topic?
A: Burk: It is crucial to address HMI change management and security systemically, as undesirable changes can be introduced by user error or malware. Change management procedures and software tools should be employed that cover the entirety of the control system and HMI infrastructure used in a facility. Reliance on manual backups leaves a manufacturer exposed to a multitude of risks, and end users will object to having to use multiple change management approaches and systems instead of one common interface. The use of an automated archival system guarantees that all back ups are in fact, backed up and filed correctly. Furthermore, it is critical that the user be able to quickly identify which version of an application should be restored.
– Questions by Mark T. Hoske, Control Engineering content manager