Performability optimization design of virtual links in AFDX networks

摘要

The Avionics Full Duplex switched Ethernet (AFDX) is widely used in the new generation of civil aircraft, such as A380 and Boeing787. Some research works have been conducted to optimize virtual links (VLs) design. However, a method that optimizes the VLs design scheme from the perspective of network performability is still missing. Furthermore, the configuration parameters interact with each other, making the optimization more complicated. Therefore, it is urgent to propose an effective and feasible optimization design scheme for VLs to improve the network performability. In this paper, we focus on optimizing the VLs design scheme in the view of Interface Control Document (ICD). Firstly, according to the ICD messages, other authors' methods are utilized to obtain the initial VLs design scheme. Secondly, two-layer network model is used to model the AFDX. According to the correspondence between the parameters with two-layer, the parameters are divided into two parts. For each layer, optimization model is established. Network calculus is utilized to calculate the end-to-end delay in the physical layer. Thirdly, we put forward the corresponding optimization algorithm. 0perations research method is used to obtain the reasonable parameters in the whole network. For the logical layer, we use an improved Frank Wolfe algorithm to get VL routing. And for the physical layer, we use heuristic algorithm to get {BAGi, Lmaxi}. At last, we evaluate the performance of the proposed scheme by a case study with airborne application flows, and the optimization results are analyzed in detail. After the optimization process, the performability meets the requirement and the average bandwidth utilization and the average end-to-end delay are observably reduced.