Ethernet and PROFINET switches

Switches are used for data exchange between controllers, PLCs and other network participants. They are therefore among the most important network components - also in terms of numbers. Even the smallest optimisations therefore have a noticeable effect on these components. This also applies to the design, because space in the control cabinet is naturally limited.

The unmanaged Ethernet switches from Helmholz set standards here with a width of only 49 mm in the 5-port version or 65 mm for 8 ports. Thanks to their very compact design, they can be used for a wide range of industrial applications. The lightweight yet robust industrial design is suitable for mounting on the top-hat rail and is very easy to integrate into the network. Once plugged in, they are immediately ready for operation thanks to the simple plug&play solution. The tool-free push-in terminal for the power supply supports fast and uncomplicated installation.
However, the use of conventional Ethernet switches in conjunction with PROFINET networks should be viewed with caution due to the lack of telegram prioritisation and the associated data load in many machine networks. Here, PROFINET switches are the much better alternative.

One of the most important functions of a PROFINET switch is the prioritisation of the PROFINET telegram traffic in the machine network. The managed switch can distinguish whether the telegram is a web request, an FTP file transfer, a media stream or a PROFINET telegram. In the event of a high transmission load, the important telegrams can thus be prioritised in order to prevent telegram losses or the PROFINET network no longer being accessible. This also means: a clear and unambiguous segmentation between Ethernet and PROFINET. Without managed PROFINET switches, many profitable features of PROFINET are lost.

Fieldbus and NAT gateways

Fieldbus gateways are hardly less frequently used than switches for connecting individual automation networks. Regardless of the network bus (PROFINET, CANopen, DP), the smallest possible design is therefore also important here. PROFINET-PROFINET gateways from Helmholz, for example, are only about a quarter as large as comparable devices from other manufacturers. Furthermore, their installation, like that of the PROFINET switches, requires no additional software tool.

With the triumph of Ethernet networking, cybersecurity also plays a very central role. Particularly in view of growing data volumes, the separation or segmentation of networks is therefore urgently recommended. In essence, this is about securely integrating machine networks into the higher-level production network. With the NAT Gateway WALL IE, Helmholz offers a solution that concentrates on the essential functions and is therefore correspondingly cost-effective: the robust and particularly compact Ethernet component combines bridge and firewall functions. It thus enables the simple integration of machine networks into the higher-level production network. As a positive effect, broadcast domains are also reduced.

In concrete terms, the component protects the networks by regulating exactly which participant is allowed to exchange data with which device. The prerequisite for this is a packet filter functionality: this allows access between the production network and the automation cell to be restricted.
As a further special feature, the WALL IE can be used both in NAT operating mode and as a bridge. In bridge operating mode, WALL IE acts as a layer 2 switch. However, unlike normal switches, packet filtering is also possible in this operating mode. This makes it possible to restrict access to individual areas of the respective network without having to use different networks for this purpose.

In router operating mode, which most users use, the WALL IE forwards data traffic between different IPv4 networks (layer 3) and uses packet filters to restrict access to the automation network behind it. Address translation using Network Address Translation (NAT) is supported. The use of NAT also makes it possible to integrate several similar automation cells with the same address range into the production network. In router operating mode, WALL IE supports two NAT functionalities: Basic NAT (also called "1:1 NAT" or "Static NAT") and NAPT (Network Address and Port Translation, also called "1:N NAT" or "Masquerading").

Secure online remote access

Last but not least, Helmholz also enables secure and simple online remote access: machine builders in particular, but also production companies, use the REX industrial routers to access the Ethernet networks of their machines and systems directly online - for remote maintenance, visualisation, data collection and for diagnostic and Web2Go (VNC and Remote Desktop) applications, for example. The REX series, which covers a broad application-specific spectrum with the REX100 and REX200/250 model series, offers various access options via Ethernet, 3G, 4G or Wifi for this purpose.

Data transmission for all REX models is generally encrypted via a VPN tunnel. The basis for this is the secure Open VPN protocol. The Helmholz IoT portal myREX24 V2 serves as the switching centre for VPN communication between the operator and its systems. Both sides can thus establish the VPN tunnel as an outgoing connection. Firewalls or restrictions imposed by services or mobile network operators are no longer an issue. Because these only affect data traffic into the network, but not out of the network. The outgoing connections then remain on hold for a short time until the VPN tunnel is established. This is where the actual communication takes place via the IoT Portal. The simple and intelligent user management and the fast configuration of the REX industrial routers have already convinced many customers during the selection process with providers of similar systems. Helmholz offers a special test account for this, so that potential customers can test the performance of the IoT Portal in detail in advance.

Conclusion

Whether Ethernet and PROFINET switches, NAT and fieldbus gateways or secure IoT remote machine access: with current solutions from Helmholz, the high demands placed on industrial networks in times of increasing automation can be fulfilled both safely and efficiently - including a high level of operating convenience and optimum utilisation of the control cabinet width.