Advanced avionic communications for military use

The three principal military high speed data bus standards are Draft Proposal STANAG 3910, SAE AS 4074.1 Linear Token Passing Bus and AS 4074.2 High Speed Ring Bus. There is a significant difference between 3910 and the SAE standards, in that 3910 makes use of the existing STANAG 3838 (Mil Std. 1553B) to control access to a high speed (20 Mbit/sec) channel. In meeting the needs of time critical systems the only difference between 3910 and 1553B is the message length that can be transmitted within the latency bounds of 1553B. Nevertheless, 3910 has a number of significant advantages for near term and retro-fit applications. In particular, the tried and tested practice of co-siting the data communications control function with the controlling system element can be retained; the way in which communications and systems control is to be achieved with truly general purpose high speed data buses such as those produced by SAE is yet to be resolved