AIAA Standard — Space Plug-and-Play Architecture: Logical Interface (AIAA S-133-3-2013e)

The logical interface of SPA is the boundary through which components participate in a SPA system. This document describes the messages that pass across the SPA interface, the circumstances under which those messages flow, and the protocols for sequencing those messages. This document does not attempt to describe how the messages are transported from one component to the other. This document and its messages are agnostic to message routing, message delivery, or the network topology.

Furthermore, this document does not attempt to describe the details on how these messages are implemented for a mission. The use of these messages can seem vague without a complete implementation or mission-specific example. The SPA Guidebook gives examples and principles on how these messages are used to achieve the capabilities of a fully functional plug-and-play architecture.