In many operators’ plants, long downtimes occur in the event of an error. The failure is often due to network problems that are time-consuming to locate without suitable information.
Diagnostics-capable devices such as the Managed Switches and WLAN access points from Phoenix Contact offer a solution.
High system availability in combination with maximum protection against unauthorized access is fundamental for the economic success of companies. That said, network diagnostics – that is, the detailed monitoring of each device, each connection, and each data communication – is primarily done to gain the information needed for a quick determination of the location and type of the problem.
Link problems, electromagnetic interferences, device errors …
Operators of machine and production networks face typical real-world challenges. Link problems are the most frequent causes for data communication failures in Ethernet networks. Usually, failures are due to loose or broken cables and connectors that either have been badly assembled or wrongly installed, for instance. Other causes include inoperative devices and high package loss rates resulting, for example, from electromagnetic interferences in the vicinity of the network cables.
When the network is not redundant, one single connection failure can lead to whole areas being disconnected, thus causing downtime. Diagnostics-capable infrastructure components help determine more quickly what type of problem has occurred and where it has happened, thanks to link down detection and comprehensive port statistics.
… network overload, and unauthorized access are typical sources of error
Another cause for network problems is network overload due to subsequently added components. Particularly in smaller networks, stability often declines when additionally installed devices lead to an increase in data traffic. This happens, for instance, when data-intensive camera systems are subsequently integrated into existing networks. Especially the real-time capability of automation networks – such as Profinet or Ethernet/IP – can suffer due to the larger amount of data. Diagnostics-capable network components, such as Managed Switches, help detect problems also in this case.
Moreover, network problems can result from unauthorized access via a free and unprotected port on a switch. Consequently, the network can be deliberately manipulated or malware can be transferred by accident via a service laptop. In addition to the protection against unauthorized external access it is thus important to control internal access to the machine and production network and to ensure that attempts to gain access to the network can be directly reported and traced by means of notifications and alarms. Doing so again requires diagnostics-capable network components. That is why many Managed Switches offer security functions that control and monitor access via the ports and report any unauthorized attempts to gain access.
Provision and mirroring of the diagnostic data
When using diagnostic-capable components from Phoenix Contact, the user has numerous ways to obtain the network data. Web-based management is a user-friendly and easy option and can be accessed using a conventional Web browser. Besides various configuration options, it provides a clear and structured overview of all diagnostic data.
The network components from Phoenix Contact also provide their diagnostic data via different standardized interfaces to users who prefer using a centralized diagnostic system. The events displayed in the event log can, for instance, also be sent as a notification to a Syslog server, if required. This technology is supported by many diagnostic systems. In Profinet and Ethernet/IP networks, the control usually reads the diagnostic data directly. This makes it possible to query data from network components – such as Managed Switches – and process the data in the control system.
For a detailed analysis of the data communication at the package level, numerous network components from Phoenix Contact include functions for port mirroring. These functions enable the entire incoming and/or outgoing data traffic at one or several ports to be copied to what is called a mirror port. Specific software tools, which record the mirrored data traffic, then help analyzing it.