Analysis of TDMA crossbar real-time switch design for AFDX networks

Abstract

Abstract-The rapid scaling up of modern avionics is forcing its communication infrastructure to evolve from shared medium toward multi-hop switched real-time networks. This prompts the proposal of avionics full-duplex switched Ethernet (AFDX) standard. Since its publication, AFDX has been well-received, and is deployed or to-be-deployed in state-of-the-art aircrafts, such as Airbus A380/A400M/A350, Boeing 787, Bombardier CSeries etc. On the other hand, AFDX standard only specifies the behavior that an underlying switch must follow, but leaves the architecture design open. This creates an open market for switch vendors. Among the different candidate designs for this market, the TDMA crossbar real-time switch architecture stands out as it complies with and even simplifies many mainstream switch architectures, hence lays a smooth evolution path toward AFDX. In this paper, we focus on analyzing this switch design for AFDX networks. We first prove that TDMA crossbar realtime switch architecture complies with the AFDX specifications; and derive closed-form formulae on the corresponding AFDX networks' traffic characteristics and end-to-end real-time delay bound. Then we prove the resource planning problem in the corresponding AFDX networks is NP-Hard. To address this NPHard challenge, we re-model the problem. Based upon the remodeling, we propose an approximation algorithm.

Asynchronous Hard Real Time Signals Transmission in Embedded Networks

“…It is targeted for using like a local bus and sends all control information, including interrupts, throw the same links, which used for data transmission [PCI SIG, 2006]. In avionics the ARINC 664 part 7 (AFDX) standard is used, which main aim is to design a deterministic data transmission network which can be used by necessary for fly control systems [ARINC Specification 664P7], [Rao, 2012]. The task of control information transmission is usually assigned to standardized communication channel which done by MIL-STD-1553В standard [MIL0STD-1553Protocol tutorial, 2010.…”