Standard Buses, Modular Buses, and Plug-and-Play Buses; What Is the Difference and Why Does It Matter?

There is significant confusion in the space industry today over the terms used to describe satellite bus architectures. Terms such as standard bus or common bus, modular bus and plug-and-play bus are often used with little understanding of what the terms actually mean, and even less understanding of what the differences in these space architectures mean. It may seem that these terms are subtle differentiators, but in reality these terms describe radically different ways to design, build, test, and operate satellites. Furthermore, these terms imply very different business models for the acquisition, operation, and sustainment of space systems. This paper will define and describe the difference between standard buses, modular buses and plug-and-play buses giving examples of each kind with a costbenefit discussion of each type.