Overview and effect of deterministic ethernet on test strategies

A trend has emerged toward the development of critical systems hosted on the Ethernet databus. Ethernet enjoys unprecedented standardization in commercial networks, and a vast network of engineers with training and experience. It is now commonly known that implementations of deterministic Ethernet for avionics networks known as ARINC 664 part 7 exist on several commercial airframes. In other platforms, Ethernet's ever increasing bandwidth leads many to the assumption that Ethernet can be made deterministic by way of excess capability alone. Standardization efforts within industry communities such as IEEE and SAE have recently expanded the number of available deterministic Ethernet options. Audio Video Bridging protocol (or AVB), now known as IEEE 802.1 TSN (Time Sensitive Networking), is progressively developing in to a deterministic, all-purpose, and standardized (Industrial, Automotive, and commercial WAN/LAN) Ethernet-based databus. SAE AS6802, also known as Time Triggered Ethernet (or TTE) has demonstrated efficacy for deterministic and mixed-criticality use of Ethernet. Ethernet's bandwidth and switched network topology require innovations to deterministic network test strategies that have led to the development of hardware and software tools designed for testing deterministic Ethernet networks. AIT's Network Data Aggregator enables test engineers to capture and timestamp all incoming and outgoing messages to a network switch, instead of using traditional network switch monitor ports. This paper examines the evolution of deterministic Ethernet and the sub-sequent effect on test strategies.