ISO/IEC/IEEE 21840:2019

This document provides guidance on the application of processes in ISO/IEC/IEEE 15288 to systems of systems (SoS). The scope of this document is the same as ISO/IEC/IEEE 15288, which addresses more than systems engineering activities.
NOTE 1 Throughout the document, there is mixed use of 'system of systems' and 'systems of systems'. 'SoS' could refer to a system of systems or systems of systems. Similarly, 'CS' could refer to a constituent system or constituent systems.
This document provides general guidance for each ISO/IEC/IEEE 15288 process and process outcome in the context of SoS, but it does not address specific activities, tasks, methods, or procedures. Additional processes and process outcomes unique to SoS can still be needed and are not covered by this document.
This document explores the similarities and differences between systems and SoS and, by extension, the similarities and differences between engineering of systems and SoS. The guidance contained in this document is expected to evolve as the discipline matures.
NOTE 2 In many cases, this document notes that ISO/IEC/IEEE 15288 processes or process outcomes 'applies as stated to SoS.' Some interpretation within the context of SoS can still be needed.