EtherNet/IP versus PROFINET
use a star topology complemented by others: Ring topology connects multiple devices sequentially — though if a cable is cut within the ring, each device maintains its path to control. Tree topology uses devices or switches wired with connections between device groupings; any break prompts an algorithm to determine the next best workable path to solution. PROFINET’s line topology uses minimal cabling and no external switches; connections to any star and tree topologies are via standalone switches. Here if a star or tree switch fails, communications to all nodes are affected — which can be problematic. So, to ensure communications continuity, PROFINET supports topologies with added devices to provide media backup and other elements should a cable or node fail. Note that EtherNet/IP and PROFINET networks deploy in systems under centralized and decentralized control — and sometimes work in systems that combine both control arrangements. With EtherNet/IP and PROFINET, centralized systems use a client-server setting having a center server connecting one or more client nodes. Client nodes submit requests to the central server rather than process on their own while the server handles all the major processing. In decentralized systems, every node autonomously executes its own logic. The final
Figure 5: PROFINET hardware excels in harsh and severe conditions subject to vibration, heat, dust, oil, and other challenging conditions. This Brad PROFINET IO-Link HarshIO module is one example of a ruggedized component for PROFINET- connected factory automation. Image source: Molex
to intended device endpoints. Ports may have an LED indicator to show the presence of data flow, but these unmanaged switches usually don’t provide much more information about or management of that data flow. In contrast, managed PROFINET switches are more intelligent and work with different IT protocols — including the simple network management protocol (SNMP) and link layer discovery protocol (LLDP) for PROFINET. Because of their intelligence, managed switches are often used where preventing downtime is a top objective — and where troubleshooting failures is useful. Of course, they’re usually costlier than unmanaged switches. Direct comparison of EtherNet/IP and PROFINET characteristics Industry-specific adaptations of EtherNet/IP are transforming many industries. For example, the packaging industry employs EtherNet/IP for high-speed communications, determinism, and real-time performance. Industries such as chemical processing, traditional automation, and power generation use EtherNet/IP to continually quantify output. Still other industrial applications involve fully automated processes that necessitate counting and real-time data acquisition for control. Here both EtherNet/IP and PROFINET excel in creating the deterministic
networks such applications require.
send and receive data over the Internet. Today, smart human- machine interfaces (HMIs) connected to networks sometimes do double-duty as gateways between automation systems and controllers as well — for simplified system commissioning and maintenance. Figure 6: This Anybus Communicator protocol-converting gateway facilitates the serial connection of non-networked equipment to PROFINET networks. Image source: HMS Networks
Consider EtherNet/ IP and PROFINET signal qualities, message sizes,
replacement. There are
actions of the system are the sum of all nodes’ logic.
cost benefits to the way existing devices can be shared and existing networks accept the addition of supplemental hardware. Even so, upfront costs for PROFINET technologies may be up to 15% more than those based on EtherNet/IP. That cost is partially offset by easier installation, estimated to be about half as complicated (read: expensive) as installation of Ethernet/IP. Topologies and components supported by EtherNet/IP and PROFINET also differ somewhat. Network topology is the arrangement of the links and nodes of a network. Links are wireless and wired technologies such as coaxial, ribbon, and twist-pair cable as well as fiber-optic cable. In contrast, network nodes are hubs, bridges, switches, routers, modems, and firewall interfaces. Topologies include star, line, ring, daisy chain, and mesh.
and update rates for details on how the two differ. PROFINET is generally faster than EtherNet/ IP and most often deployed with standard hardware, though PROFINET IRT requires specific hardware. EtherNet/IP is more interoperable, as it’s based on object-oriented programming and relies on commercial off-the- shelf (CotS) components. In fact, that use of CotS components and hardware not unlike the ubiquitous variations employed in office settings means EtherNet/IP is very cost effective for high-speed industrial connectivity. Economies of scale and the interchangeable nature of much of this hardware help minimize upfront costs the most. In contrast, PROFINET-ready components can integrate into PROFIBUS-based fieldbuses, effectively capable of supplementing existing systems without necessitating complete
EtherNet/IP and PROFINET gateways Gateways (whether standalone pieces of hardware or integrated with router, firewall, or server functions) control the flow of data in and out of a given network and sometimes between disparate systems. That includes some gateways that are specifically designed to communicate I/O between EtherNet/IP and PROFINET networks. For the latter, most gateways function as a PROFINET device and EtherNet/IP adapter for automatic compatibility. Besides their primary role, gateways can also unburden a system’s PLC of signal timing, counting, calculating, comparing, and processing tasks. EtherNet/ IP and PROFINET gateways with router functionality let computers
Connecting future industrial automation installations
EtherNet/IP and PROFINET connectivity are enabling
innovative new permutations of automation and industrial controls with unprecedented agility and IIoT functionality. As hardware, software, and connectivity technologies leverage EtherNet/IP and PROFINET in new ways, they’ll help systems meet evermore- demanding industrial production requirements.
EtherNet/IP networks primarily
we get technical
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