PROFINET: Өнеркәсіптік Ethernet желісінің қауіпсіздігі мен сенімділігі

Computer network protocol

Profinet (usually styled as PROFINET, as a portmanteau for Process Field Network) is an industry technical standard for data communication over Industrial Ethernet, designed for collecting data from, and controlling equipment in industrial systems, with a particular strength in delivering data under tight time constraints. The standard is maintained and supported by Profibus and Profinet International, an umbrella organization headquartered in Karlsruhe, Germany.

Profinet implements the interfacing to peripherals.

A Profinet system consists of the following devices: or PRONETA.

Profinet is also increasingly being used in critical applications. There is always a risk that the required functions cannot be fulfilled. This risk can be reduced by specific measures as identified by a dependability analyses. The following objectives are in the foreground:
Safety: Ensuring functional safety. The system should go into a safe state in the event of a fault. Availability: Increasing the availability. In the event of a fault, the system should still be able to perform the minimum required function. Security: Information security is to ensure the integrity of the system. These goals can interfere with or complement each other.

High availability is one of the most important requirements in industrial automation, both in factory and process automation. The availability of an automation system can be increased by adding redundancy for critical elements. A distinction can be made between system and media redundancy.

System redundancy can also be implemented with Profinet to increase availability. In this case, two IO Controllers that control the same IO Device are configured. The active IO Controller marks its output data as primary. Output data that is not marked is ignored by an IO Device in a redundant IO System. In the event of an error, the second IO Controller can therefore take control of all IO Devices without interruption by marking its output data as primary. How the two IO Controllers synchronize their tasks is not defined in Profinet and is implemented differently by the various manufacturers offering redundant control systems.

Profinet offers two media redundancy solutions. The Media Redundancy Protocol (MRP) allows the creation of a protocol independent ring topology with a switching time of less than 50 ms. This is often sufficient for standard real time communication with Profinet. To switch over the redundancy in the event of an error without time delay, the "Media Redundancy for Planned Duplication" (MRPD) must be used as a seamless media redundancy concept. In the MRPD, the cyclic real time data is transmitted in both directions in the ring shaped topology. A time stamp in the data packet allows the receiver to remove the redundant duplicates.

The IT security concept for Profinet assumes a defense in depth approach. In this approach, the production plant is protected against attacks, particularly from outside, by a multi level perimeter, including firewalls. In addition, further protection is possible within the plant by dividing it into zones using firewalls. In addition, a security component test ensures that the Profinet components are resistant to overload to a defined extent. This concept is supported by organizational measures in the production plant within the framework of a security management system according to ISO 27001.

PROFIdrive is the modular device profile for drive devices. It was jointly developed by manufacturers and users in the 1990s and since then, in conjunction with Profibus and, from version 4.0, also with Profinet, it has covered the entire range from the simplest to the most demanding drive solutions.

Another profile is PROFIenergy which includes services for real time monitoring of energy demand. This was requested in 2009 by the AIDA group of German automotive Manufacturers (Audi, BMW, Mercedes Benz, Porsche and Volkswagen ) who wished to have a standardised way of actively managing energy usage in their plants. High energy devices and sub systems such as robots, lasers and even paint lines are the target for this profile, which will help reduce a plant's energy costs by intelligently switching the devices into 'sleep' modes to take account of production breaks, both foreseen (e. g. weekends and shut downs) and unforeseen (e. g. breakdowns).

Modern process devices have their own intelligence and can take over part of the information processing or the overall functionality in automation systems. For integration into a Profinet system, a two wire Ethernet is required in addition to increased availability.

Ethernet Advanced Physical Layer (Ethernet APL) describes a physical layer for the Ethernet communication technology which is especially developed for the requirements of the process industries. The development of Ethernet APL was determined by the need for communication at high speeds and over long distances, the supply of power and communications signals via common single, twisted pair (2 wire) cable as well as protective measures for the safe use within explosion hazardous areas. Ethernet APL opens the possibility for Profinet to be incorporated into process instruments.

At the general meeting of the Profibus user organisation in 2000, the first concrete discussions for a successor to Profibus based on Ethernet took place. Just one year later, the first specification of Component Based Automation (CBA) was published and presented at the Hanover Fair. In 2002, the Profinet CBA became part of the international standard IEC 61158 / IEC 61784 1. A Profinet CBA system consists of different automation components. One component comprises all mechanical, electrical and information technology variables. The component may have been created with the usual programming tools. To describe a component, a Profinet Component Description (PCD) file is created in XML. A planning tool loads these descriptions and allows the logical connections between the individual components to be created to implement a plant. The basic idea behind Profinet CBA was that in many cases it is possible to divide an entire automation system into autonomously operating and thus manageable subsystems. The structure and functionality may well be found in several plants in identical or slightly modified form. Such so called Profinet components are normally controlled by a manageable number of input signals. Within the component, a control program written by the user executes the required functionality and sends the corresponding output signals to another controller. The communication of a component based system is planned instead of programmed. Communication with Profinet CBA was suitable for bus cycle times of approx. 50 to 100 ms. Individual systems show how these concepts can be successfully implemented in the application. However, Profinet CBA does not find the expected acceptance in the market and will no longer be listed in the IEC 61784 1 standard from the 4th edition of 2014. In 2003 the first specification of Profinet IO (IO = Input Output) was published. The application interface of the Profibus DP (DP = Decentralized Periphery), which was successful on the market, was adopted and supplemented with current protocols from the Internet. In the following year, the extension with isochronous transmission follows, which makes Profinet IO suitable for motion control applications. Profisafe is adapted so that it can also be used via Profinet. With the clear commitment of AIDA to Profinet in 2004, acceptance in the market is given. In 2006 Profinet IO becomes part of the international standard IEC 61158 / IEC 61784 2. In 2007, according to the neutral count, 1 million Profinet devices have already been installed, in the following year this number doubles to 2 million. By 2019, a total of 26 million devices sold by the various manufacturers are reported. In 2019, the specification for Profinet was completed with Time Sensitive Networking (TSN), thus introducing the CC D conformance class.