AFDX (Avionics Full Duplex Switched Ethernet) end-to-end delay bound claculation method based on random network calculus

Abstract

The invention discloses an AFDX (Avionics Full Duplex Switched Ethernet) end-to-end delay bound claculation method based on a random network calculus. The method comprises the following four steps of: firstly, determining a flow chart of a dataflow in an entire network, and drawing out the flow chart of the dataflow; secondly, analyzing a constituent part of an end-to-end delay of the dataflow in the entire network, thereby obtaining a constituent form of a fixed delay and a variable delay of the end-to-end delay; thirdly, calculating the variable delay; and fourthly, obtaining an end-to-end delay bound of the dataflow to be analyzed. According to the invention, influence of the dataflow is taken into consideration in case of a random interference or an emergency, and a greater grain is achieved from statistics of a duplex independent communication flow; meanwhile, influences of high/low priority configuration and a scheduling algorithm on the delay in an exchanger are taken into full consideration, therefore, not only can an end-to-end delay bound value be precisely obtained and unnecessary resource waste can be avoided, but a network performance can be predicated in a design stage, waste is avoided when an actually-built network is unqualified.

Description

technical field [0001] The invention provides a calculation method for an upper bound value of an AFDX end-to-end time delay, in particular relates to a method for calculating an upper bound of an AFDX end-to-end time delay based on random network calculus, which belongs to the technical field of electronic information. Background technique [0002] AFDX is a network suitable for the interconnection of avionics systems formed on the basis of the industry standard IEEE802.3 Ethernet after supplementation, modification and limitation. The transmission speed can reach 100Mbps. With the successful application in the Airbus A380 in the 1990s And developed rapidly. Since AFDX mainly provides data exchange between avionics equipment, ensuring timely and accurate data transmission is the primary goal of its design, so accurate evaluation of AFDX end-to-end delay is very necessary. [0003] At present, most researches on the end-to-end delay of AFDX mainly include two methods: simul...

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Problems solved by technology

[0006] The purpose of the present invention is to solve the problem that the upper bound of the end-to-end delay in the AFDX network is too large, and to provide a method for calculating the upper bound of the end-to-end delay of AFDX based on random network calculus. It proposes a method that considers service flow priority The analysis model of the impact delay of level scheduling can calculate the more accurate upper limit value of AFDX end-to-end delay

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