Access and Control Series: Remote Access Control Technologies Advantages & Disadvantages
August 20, 2012
Remote Access Control Technologies to Improve Plant Operations
Remote access and control technologies have been around for quite some time. This is thanks, in part, to Internet protocol (IP)-based virtual private networks (VPNs).
Grantek typically applies a unified system architecture using open, industry-standard networking technologies, but customizes the technology choices and design for each customer. We apply remote asset control technologies that best fit the security policies and unified threat management (UTM) or firewall devices being used.
This is important because we are typically using or adapting the access methodologies that are sponsored by the corporate IT entity. The security devices need to be configured to the unique constraints of an automation system and a multi-level architecture. Grantek also works with the manufacturing and IT departments within an organization to determine the best connectivity technologies for their applications. This typically includes the implementation of internally managed application software that is accessed by external resources.
For example, a terminal server is installed at a facility to provide access to programming software from a variety of software vendors. This terminal server would be set up to have all of the pre-configured links, shortcuts and supported versions of the required software to manage the plant floor assets. Additionally, the terminal server is also configured to utilize the facility’s asset management system so all source code is tracked and version controlled, whether or not changes are made by resources that are internal or access the systems remotely. Consideration of not only the network access but also how the remote user will interact with the application is crucial to the successful implementation of a remote access strategy.
Successful implementation of remote access to factory automation systems requires early collaboration between IT and manufacturing organizations.
Advantages and Disadvantages of Remote Access Control Technologies
The greatest advantage of a unified system architecture with open, industry-standard network technologies, such as Ethernet, is the security it provides. Users that connect to a network via modem, cellular or DSL line may be inadvertently exposing their network to unexpected hazards. While these techniques are easier to implement and provide direct access to the devices, they circumvent perimeter security defenses and don’t have the visibility and support of the IT organization.
To maintain strict control of remote access, it is best to keep automation and control protocol at “home,” or in the manufacturing zone. Limiting the protocols to this zone helps ensure that the plant automation and control devices are communicating with known devices and applications (including versions). It also can help ensure user authentication and role-based authorization. These types of security measures can also help prevent an accidental transfer of a virus from an engineer’s home computer to a plant-floor control system.
By implementing secure access control technologies, factory automation systems can be quickly and safely accessed which can result in improved plant efficiency.