Category Archives: publication

Modeling and Analysis of Interoperabiliity Risk in Systems of Systems Environments

by Philip Boxer

CrossTalk, The Journal of Defense Software Engineering, has published an article on the Modeling and Analysis of Interoperability Risk in Systems of Systems Environments in its November 2008 Issue.  The abstract is as follows:

This article describes the use of a set of modeling and analysis techniques in an interoperability risk probe that found gaps in the ability of a North Atlantic Treaty Organization (NATO) modernization program to react to changing demands. The modeling and analysis techniques were used to create models of the people, processes, and technologies of the program and to represent the way demands were placed on this complex socio-technical system. Analysis of the models revealed interoperability risks that were manifested in the linkages between operational requirements of functional capabilities and the way in which those capabilities were being maintained. The risks identified in this probe were typed as mission, composition, and performance risks. The structural models produced by the techniques bring a welcome engineering rigor to the process of examining interoperability.

The article, by Bill Anderson and Philip Boxer, summarises work done originally in 2006 by Boxer Research Ltd under contract to the Software Engineering Institute at Carnegie Mellon University.

Understanding and factoring in variability in the execution of SoS functionality

by Philip Boxer

The Office of the Secretary of Defense (OSD) has released a Systems Engineering Guide for Systems of Systems.  It “addresses SE considerations to meet capability needs through integrating independently useful systems into a larger system that delivers unique capabilities – a system of systems (SoS) – within the Department of Defense”.

The guide references the work on the Pragmatics of Demand as follows:

The architecture of an SoS is somewhat constrained by the structure and content of the individual systems, particularly the extent to which changes in those systems are affordable and feasible, since systems will typically need to continue to function in other settings in parallel with participation in the SoS. The functionality that the individual systems contribute to the SoS can be described in a functional architecture that puts the key functions in order, thereby sequencing the SoS tasks. An example is the ballistic missile defense end-to-end process through boost, mid-course, and terminal phases of ballistic missile threats which would serve as the framework for this functional process in the case of one SoS. The functional architecture provides a functional ‘picture’ of the system. It details the complete set of functions to be performed within the SoS as well as the relationships among the functions. The output of the design process is the design of the SoS, or the physical architecture that defines the physical components (constituent systems) of which the SoS will be composed. The variability in the execution of these functions in the field also needs to be understood and factored into the SoS architecture [Boxer, 2008].

This version of the document does not go on to describe the methods for analysing this variability, outlined in the work with Thales UK in terms of agility and innovation. However, it does reference the earlier work on the Navigator approach to managing system-of-systems interoperability:

Finally, the SoS systems engineer is challenged to develop approaches to evolve the ensemble of systems to meet new needs while accommodating the independently owned and funded constituent systems, which themselves are often evolving to meet their own system users’ needs. To attain this delicate balance and support decisions that are typically outside of the SE purview, the SoS systems engineer must understand systems and their relationships from multiple perspectives, including technical and organizational relationships. These decisions include analysis of options and trades for SoS design/architecture given current characteristics and development plans of systems; assessments to determine which requirements can be addressed in what time frame given system objectives, funding, and development schedules; and analysis of how internal and external changes will affect the SoS. Several activities, including the Software Engineering Institute’s SoS Navigator initiative, are examining these needs and approaches [Brownsword, Fisher, Morris, Smith & Kirwan, 2006].

Requisite Agility

by Philip Boxer

This article by Bill Anderson and Philip Boxer on Requisite Agility argues that the socio-technical processes required to respond to changing demand can be described (modeled) and better equipped to handle change if the organization is driven from a demand-side perspective rather than from a supply-side perspective.  The ability to do this increases the potential for software services acting as constituent parts to automate more and more parts of the existing geometry-of-use space in order to create new possibilities on the demand side.

Systems-of-Systems Engineering and the Pragmatics of Demand

by Philip Boxer

Last week I was joined by Bernie Cohen and colleagues from the SEI to present this paper at the IEEE 2nd International Systems Conference in Montreal, Canada (April 7-10, 2008).

The paper considers how the particular pragmatics of demand ‘at the edge’ determine the forms of interoperability required of complex systems of systems, which we refer to as ‘geometries-of-use’. The importance of this concept lies in its use to determine the requisite variety of geometries-of-use that a systems of systems infrastructure needs to be able to support. From this we can determine the functional granularity required of the supporting infrastructures.

Dynamic Systems at SEI

by Philip Boxer

I have been a strategy consultant to organisations for over 20 years, supporting leadership teams across many different industry sectors, both public and private. My focus has been on the challenges organisations face from asymmetric forms of demand and the mitigation of risks associated with failing to develop requisite agility. This blog has traced some of the ideas emerging from this work, and I have developed a number of methods and tools needed to support strategy formation and collaborative design processes, including visual PAN and its associated forms of analysis. In 2006, a report was published detailing an application of this form of structural modeling (An Examination of a Structural Modeling Risk Probe Technique), written by staff at the Software Engineering Institute (SEI) at Carnegie Mellon University.

In March 2007 I started work as a senior member of technical staff working with the Integration of Software Intensive Systems (ISIS) team, within the Dynamic Systems Programme at SEI. The aim of this work is to bring visual PAN and its associated forms of analysis into the public domain.