Method for realizing deterministic communication dispatch of ethernet

Abstract

In the method information in network is divided into period information and non-period information. Control mode of time slot access is adopted for period information. Periodic data exchange is carried out in fixed time slice. Centralized dispatching mode based on token is adopted for non-period information, and communication of non-period information is carried out in interval between periodic information communications. At least one master device and one or multiple slave devices are defined on network for the dispatching method. Only obtaining token from master device, slave device is enabling to send non-period information. At least one clock is setup in network for clock synchronization for each device. The invention dispatches periodic and non-period information in Ethernet reasonably, realizing communication in real time and determinacy in industrial control network based on Ethernet + UDP / IP.

Description

technical field [0001] The invention relates to a scheduling method for Ethernet communication, in particular to a scheduling method for deterministic communication between multiple network nodes in an industrial control network based on Ethernet+UDP / IP. Background technique [0002] As a mature network technology, Ethernet has many advantages such as low cost, stability and reliability, etc. It has been widely used in the field of office automation and industrial control, and has become one of the most popular communication networks. The currently used Ethernet standards mostly use the CSMA / CD protocol with collision detection in the MAC (Media Access Control) layer. The working process is: when a certain node on a network needs to send data, It first monitors the channel, and if the channel is busy, it continues to wait until it detects that the channel is free, and then sends the data. If two or more nodes are listening and waiting to send data, when the channel is detec...

AI Technical Summary

Problems solved by technology

The advantage of this master-slave transmission control method is that it can ensure that each slave device has the opportunity to send data, but the disadvantage is that it cannot handle sudden communications in the industrial control network, such as alarm information in the industrial control network

[0006] Therefore, although the above methods have improved the real-time and certainty of Ethernet transmission to a certain extent, they are either at the expense of changing the Ethernet structure (such as CSMA / DCR), or at a lower network level (such as the MAC layer). The biggest disadvantage of these methods is that they are difficult to implement, often involve hardware, and cannot be compatible with traditional standard Ethernet, and cannot meet the requirements of two types of information in industrial control networks—periodic information (that is, real-time information) Special requirements for simultaneous processing with non-periodic information (usually non-real-time information)

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