Eternal vigilance isn't just the price of freedom. It's the cost of a bunch of other items too, such as responsible parenting, nuclear weapons inspecting, healthy weight loss and industrial network maintenance. And because all these worthwhile efforts are so difficult to do on our own, and because their demands and parameters often change so quickly, it's vital to have some backup from a supportive group or team.
This was one of the reminders that came from researching and reporting this month's cover article on maintaining network health in Industrial Networking. The first thing I learned was that industrial network components merit the same awareness and maintenance as the controls whose data they convey—and that many end users still need to wake up to giving their networks that same care. However, the second thing I learned is that routine coordination and a little teamwork is what allows these best practices to get established and grow—along with using network management software (NMS) and several longstanding, IT-based diagnostic tools, such as free Wireshark software, and following Simple Network Management Protocol (SNMP), Internet Group Management Protocol (IGMP) and others.
Likewise, a growing number of suppliers have gone beyond the usual technical support and have developed always-on services and hardware devices to help check and maintain users' industrial networks. For example, Emerson Process Management is offering its System Health Monitoring (SHM) service that constantly monitors its subscribers' networks, and emails any problems it detects to the Remote Monitoring Team at Emerson's Global Services Center (GSE).
Established in 2008 and expanded worldwide in 2011, SHM begins with a Linux-based PC with a 1-megabyte kernel and four Ethernet ports in a hardened box. It's installed at the subscriber's facility, which might seem odd in a world of increasingly virtualized and cloud-based computing. However, Kevin Lange, administrator of Emerson's Lifecycle Care System, reports that each SHM box allows the service to monitor subscribers' networks from behind their firewalls, and use their email servers, but do it without directly exposing those networks to the Internet or risking the loss of intellectual property.
"SHM is a lot like the OnStar emergency response service for cars, but ours can help find likely root causes of process control problems," says Lange. "SHM can monitor the many health parameters of PLCs, I/O cards, Ethernet switches, firewalls and other devices from Emerson and other suppliers; filter those values down to core parameters that the user most needs to know about; communicate updates every five minutes; establish critical limits; and perform three retries when communicating to eliminate false positives. When the network has a problem, the remote monitoring team at GSE communicates with the local service department, and it works with the user to solve it."
Lange adds that parameters that get checked on a managed Ethernet switch include temperature, power, availability, port status, packet errors, and even ages of antivirus signatures for security. "SHM has already had multiple successes, such as pointing out overheating switches in remote cabinets where the air conditioning was down or showing that an invalid laptop was throwing out bad packets while it was plugged into an Ethernet switch," he says.
Many network users previously used protocols like SNMP on their own to monitor Ethernet switches. However, as these devices multiplied, and their networks grew more complex, many users have sought standard, automated tools such as SHM to manage and support the health of their systems. "Users want to be free to focus on their manufacturing applications, and so services like SHM can help them do it, but still give their networks the assistance they need," adds Lange.