States are used to describe relevant aspects in contexts and how the changes are to affect systems representations and behaviors.
On that account, events and states are complementary: the former are to notify relevant changes, the latter are to represent the partitions (²) that makes these changes relevant. Transitions are used to map the causes and effects of changes.
State of physical objects.
State of processes’ execution.
State of actors’ expectations.
State of symbolic representations.
Beside alignment with events, defining states consistently across objects, processes, and actors is to significantly enhance the traceability and transparency of architectures designs.
Agile and phased development solutions are meant to solve different problems and therefore differ with artifacts and activities; that can be illustrated by requirements, understood as dialogs for the former, etched statements for the latter.
Ignoring that distinction is to make stories stutter from hiccupped iterations, or phases sputter along ripped milestones.
Agile & Phased Tell Different Stories Differently
As illustrated by ill-famed waterfall, assuming that requirements can be fully set upfront often put projects at the hazards of premature commitments; conversely, giving free rein to expectations could put requirements on collision courses.
That apparent dilemma can generally be worked out by setting apart business outlines from users’ stories, the latter to be scripted and coded on the fly (agile), the former analysed and documented as a basis for further developments (phased). To that end project managers must avoid a double slip:
Mission creep: happens when users’ stories are mixed with business models.
Jump to conclusions: happens when enterprise business cases prevail over the specifics of users’ concerns.
Interestingly, the distinction between purposes (users concerns vs business functions) can be set along one between language semantics (natural vs modeling).
Semantics: Capture vs Analysis
Beyond methodological contexts (agile or phased), a clear distinction should be made between requirements capture (c) and modeling (m): contrary to the former which translates sequential specifications from natural to programming (p) languages without breaking syntactic and semantic continuity, the latter carries out a double translation for dimension (sequence vs layout) and language (natural vs modeling.)
The continuity between natural and programming languages is at the root of the agile development model, enabling users’ stories to be iteratively captured and developed into code without intermediate translations.
That’s not the case with modeling languages, because abstractions introduce a discontinuity. As a corollary, requirements analysis is to require some intermediate models in order to document translations.
The importance of discontinuity can be neatly demonstrated by the use of specialization and generalization in models: the former taking into account new features to characterize occurrences (semantic continuity), the latter consolidating the meaning of features already defined (semantic discontinuity).
As noted above, users’ stories can be continuously developed into code because a semantic continuity can be built between natural and programming languages statements. That necessary condition is not a sufficient one because users’ stories have also to stand as complete and exclusive basis for applications.
Such a complete and exclusive mapping to application is de-facto guaranteed by continuous and incremental development, independently of the business value of stories. Not so with intermediate models which, given the semantic discontinuity, may create back-doors for broader concerns, e.g when some features are redefined through generalization. Hence the benefits of a clarity of purpose:
Users’ stories stand for specific requirements meant to be captured and coded by increments. Documentation should be limited to application maintenance and not confused with analysis models.
Use cases should be introduced when stories are to be consolidated or broader concerns factored out , e.g the consolidation of features or business cases.
Sorting out the specifics of users concerns while keeping them in line with business models is at the core of business analysts job description. Since that distinction is seldom directly given in requirements, it could be made easier if aligned on modeling options: stories and specialization for users concerns, models and generalization for business features.
From Stories to Cases
The generalization of digital environments entails structural and operational adjustments within enterprise architectures.
At enterprise level the integration of homogeneous digital flows and heterogeneous symbolic representations can be achieved through enterprise architectures and profiled ontologies. But that undertaking is contingent on the way requirements are first dealt with, namely how the specifics of users’ needs are intertwined with business designs.
As suggested above, modeling schemes could help to distinguish as well as consolidate users narratives and business outlooks, capturing the former with users’ stories and the latter with use cases models.
That would neatly align means (part played by supporting systems) with ends (users’ stories vs business cases):
Users’ stories describe specific objectives independently of the part played by supporting systems.
Use cases describe the part played by systems taking into account all supported stories.
It must be stressed that this correspondence is not a coincidence: the consolidation of users’ stories into broader business objectives becomes a necessity when supporting systems are taken into account, which is best done with use cases.
Aligning Stories with Cases
Stories and models are orthogonal descriptions, the former being sequenced, the latter laid out; it ensues that correspondences can only be carried out for individuals uniformly identified (#) at enterprise and systems level, specifically: roles (aka actors), events, business objects, and execution units.
It must be noted that this principle is supposed to apply independently of the architectures or methodologies considered.
With continuity and consistency of identities achieved at architecture level, the semantic discontinuity between users’ stories and models (classes or use cases) can be managed providing a clear distinction is maintained between:
Modeling abstractions, introduced by requirements analysis and applied to artifacts identified at architecture level.
The semantics of attributes and operations, defined by users’ stories and directly mapped to classes or use cases features.
Finally, stories and cases need to be anchored to epics and enterprise architecture.
Business Cases & Enterprise Stories
Likening epics to enterprise stories would neatly frame the panoply of solutions:
At process level users’ stories and use cases would be focused respectively on specific business concerns and supporting applications.
At architecture level business stories (aka epics) and business cases (aka plots) would deal respectively with business models and objectives, and supporting systems capabilities.
That would provide a simple yet principled basis for enterprise architectures governance.
Digital environments and the ubiquity of software in business processes introduces a new perspective on value chains and the assessment of supporting applications.
At the same time, as software designs cannot be detached of architectures capabilities, the central question remains of allocating costs and benefits between primary and support activities .
Value Chains & Activities
The concept of value chain introduced by Porter in 1985 is meant to encompass the set of activities contributing to the delivery of a valuable product or service for the market.
Taking from Porter’s generic model, various value chains have been refined according to business specific categories for primary and support activities.
Whatever their merits, these approaches are essentially static and fall short when the objective is to trace changes induced by business developments; and that flaw may become critical with the generalization of digital business environments:
Given the role and ubiquity of software components (not to mention smart ones), predefined categories are of little use for impact analysis.
When changes in value chains are considered, the shift of corporate governance towards enterprise architecture puts the focus on assets contribution, cutting down the relevance of activities.
Hence the need of taking into account changes, software development, and enterprise architectures capabilities.
Value Added & Software Development
While the growing interest for value chains in software engineering is bound to agile approaches and business driven developments, the issue can be put in the broader perspective of project planning.
With regard to assessment,stakeholders, start with business opportunities and look at supporting systems from a black box perspective; in return, software providers are to analyze requirements from a white box perspective, and estimate corresponding development effort and time delivery.
Assuming transparency and good faith, both parties are meant to eventually align expectations and commitments with regard to features, prices, and delivery.
With regard to policies, stakeholders put the focus on returns on investment (ROI), obtained from total cost of ownership, quality of service, and timely delivery. Providers for their part try to minimize development costs while taking into account effective use of resources and costs of opportunities. As it happens, those objectives may be carried on as non-zero sum games:
Business stakeholders foretell the actualized returns (a) to be expected from the functionalities under consideration (b).
Providers consider the solutions (b’) and estimate actualized costs (a’).
Stakeholders and providers agree on functionalities, prices and deliveries (c).
Assuming that business and engineering environments are set within different time-frames, there should be room for non-zero-sum games winding up to win-win adjustments on features, delivery, and prices.
Continuous vs Phased Alignments
Notwithstanding the constraints of strategic planning, business processes are by nature opportunistic, and their ability to be adjusted to circumstances is becoming all the more critical with the generalization of digital business environments.
Broadly speaking, the squaring of supporting applications to business value can be done continuously or by phases:
Phased alignments start with some written agreements with regard to features, delivery, and prices before proceeding with development phases.
Continuous alignment relies on direct collaboration and iterative development to shape applications according to business needs.
Beyond sectarian controversies, each approach has its use:
Continuous schemes are clearly better at harnessing value chains, providing that project teams be allowed full project ownership, with decision-making freed of external dependencies or delivery constraints.
Phased schemes are necessary when value chains cannot be uniquely sourced as they take roots in different organizational units, or if deliveries are contingent on technical constraints.
In any case, it’s not a black-and-white alternative as work units and projects’ granularity can be aligned with differentiated expectations and commitments.
Work Units & Architecture Capabilities
While continuous and phased approaches are often opposed under the guises of Agile vs Waterfall, that understanding is misguided as it extends the former to a motley of self-appointed agile schemes and reduces the latter to an ill-famed archetype.
Instead, a reasoned selection of a development models should be contingent on the problems at hand, and that can be best achieved by defining work-units bottom-up with regard to the capabilities targeted by requirements:
Development patterns could then be defined with regard to architecture layers (organization and business, systems functionalities, platforms implementations) and capabilities footprint:
Phased: work units are aligned with architecture capabilities, e.g : business objects (a), business logic (b), business processes (c), users interfaces (d).
Iterative: work units are set across capabilities and defined dynamically according to development problems.
That would provide a development framework supporting the assessment of iterative as well as phased projects, paving the way for comprehensive and integrated impact analysis.
Value Chains & Architecture Capabilities
As far as software engineering is concerned, the issue is less the value chain itself than its change, namely how value is to be added along the chain.
To summarize, the transition to this layout is carried out in two steps:
Conceptually, Zachman’s original “Why” column is translated into a line running across column capabilities.
Graphically, the five remaining columns are replaced by embedded pentagons, one for each architecture layer, with the new “Why” line set as an outer layer linking business value to architectures capabilities:
That apparently humdrum transformation entails a significant shift in focus and practicality:
The focus is put on organizational and business objectives, masking the ones associated to systems and platforms layers.
It makes room for differentiated granularity in the analysis of value, some items being anchored to specific capabilities, others involving cross dependencies.
Value chains can then be charted from business processes to supporting architectures, with software applications in between.
As pointed above, the crumbling of traditional fences and the integration of enterprise architectures into digital environments undermine the traditional distinction between primary and support activities.
To be sure, business drive is more than ever the defining factor for primary activities; and computing more than ever the archetype of supporting ones. But in between the once clear-cut distinctions are being blurred by a maze of digital exchanges.
In order to avoid a spaghetti heap of undistinguished connections, value chains are to be “colored” according to the nature of links:
Between architectures capabilities: business and organization (enterprise), systems functionalities, or platforms and technologies.
Between architecture layers: engineering processes.
When set within that framework, value chains could be navigated in both directions:
For the assessment of applications developed iteratively: business value could be compared to development costs and architecture assets’ depreciation.
For the assessment of features (functional or non functional) to be shared across business applications: value chains will provide a principled basis for standard accounting schemes.
Combined with model based system engineering that could significantly enhance the integration of enterprise architecture into corporate governance.
Computation independent models (CIMs) describe organization and business processes independently of the role played by supporting systems.
Platform independent models (PIMs) describe the functionalities supported by systems independently of their implementation.
Platform specific models (PSMs) describe systems components depending on platforms and technologies.
Engineering processes can then be phased along architecture layers (a), or carried out iteratively for each application (b).
When set across activities value chains could be engraved in CIMs and refined with PIMs and PSMs(a). Otherwise, i.e with business value neatly rooted in single business units, value chains could remain implicit along software development (b).
As originally defined by Ivar Jacobson, uses cases (UCs) are focused on the interactions between users and systems. The question is how to associate UC requirements, by nature local, concrete, and changing, with broader business objectives set along different time-frames.
Backing Use Cases
On the system side UCs can be neatly traced through the other UML diagrams for classes, activities, sequence, and states. The task is more challenging on the business side due to the diversity of concerns to be defined with other languages like Business Process Modeling Notation (BPMN).
Broadly speaking, tracing use cases to their business environments have been undertaken with two approaches:
Differentiated use cases, as epitomized by Alister Cockburn’s seminal book (Readings).
Business use cases, to be introduced beside standard (often renamed as “system”) use cases.
As it appears, whereas Cockburn stays with UCs as defined by Jacobson but refines them to deal specifically with generalization, scaling, and extension, the second approach introduces a somewhat ill-defined concept without setting apart the different concerns.
Differentiated Use Cases
Being neatly defined by purposes (aka goals), Cockburn’s levels provide a good starting point:
Users: sea level (blue).
Summary: sky, cloud and kite (white).
Functions: underwater, fish and clam (indigo).
As such they can be associated with specific concerns:
Blue level UCs are concrete; that’s where interactions are identified with regard to actual agents, place, and time.
White level UCs are abstract and cannot be instanciated; cloud ones are shared across business processes, kite ones are specific.
Indigo level UCs are concrete but not necessarily the primary source of instanciation; fish ones may or may not be associated with business functions supported by systems (grey), e.g services , clam ones are supposed to be directly implemented by system operations.
As illustrated by the example below, use cases set at enterprise or business unit level can also be concrete:
Compared to Cockburn’s efficient (no new concept) and clear (qualitative distinctions) scheme, the business use case alternative adds to the complexity with a fuzzy new concept based on quantitative distinctions like abstraction levels (lower for use cases, higher for business use cases) or granularity (respectively fine- and coarse-grained).
At first sight, using scales instead of concepts may allow a seamless modeling with the same notations and tools; but arguing for unified modeling goes against the introduction of a new concept. More critically, that seamless approach seems to overlook the semantic gap between business and system modeling languages. Instead of three-lane blacktops set along differentiated use cases, the alignment of business and system concerns is meant to be achieved through a medley of stereotypes, templates, and profiles supporting the transformation of BPMN models into UML ones.
But as far as business use cases are concerned, transformation schemes would come with serious drawbacks because the objective would not be to generate use cases from their business parent but to dynamically maintain and align business and users concerns. That brings back the question of the purpose of business use cases:
Are BUCs targeting business logic ? that would be redundant because mapping business rules with applications can already be achieved through UML or BPMN diagrams.
Are BUCs targeting business objectives ? but without a conceptual definition of “high levels” BUCs are to remain nondescript practices. As for the “lower levels” of business objectives, users’ stories already offer a better defined and accepted solution.
If that makes the concept of BUC irrelevant as well as confusing, the underlying issue of anchoring UCs to broader business objectives still remains.
Conclusion: Business Case for Use Cases
With the purposes clearly identified, the debate about BUC appears as a diversion: the key issue is to set apart stable long-term business objectives from short-term opportunistic users’ stories or use cases. So, instead of blurring the semantics of interactions by adding a business qualifier to the concept of use case, “business cases” would be better documented with the standard UC constructs for abstraction. Taking Cockburn’s example:
Different levels of abstraction can be combined, e.g:
Business rules at enterprise level: “Handle Claim” (19) is focused on claims independently of actual use cases.
Interactions at process level: “Handle Claim” (21) is focused on interactions with Customer independently of claims’ details.
Broader enterprise and business considerations can then be documented depending on scope.
Whenever software engineering problems are looked at, the blame is generally put on requirements, with each side of the business/system divide holding the other responsible.
The iStar approach tries to tackle the problem with a conceptual language focused on interactions between business processes and supporting systems.
Conceptual approaches to requirements try to breach the dilemma between phased and agile development schemes: the former takes for granted that requirements can be fully and definitively set upfront; the latter takes a more pragmatic path and tries to reconcile business and system analysts through direct and continuous collaboration.
Setting apart frictions between specific methods, the benefits of agile principles and practices are now well-recognized, contingent on the limits of agile scope. Summarily, agile development is at its best when requirements capture and analysis can be weaved with development and tests. The question remains of what happens when requirements are to be dealt with separately.
The iStar’s answer shares with agile a focus on collaboration and doesn’t take side for business (e.g users’ stories) or systems (e.g use cases). Instead, iStar modeling language is meant to support a conceptual description of interactions between business processes and supporting systems in terms of actors’ goals and commitments, and the associated dependencies.
Actors & Goals
The defining aspect of the iStar modeling approach is to replace one-sided perspectives (business or system) by a systemic one focused on the interactions between agents. The interactive part of a requirement will therefore comprise three basic items:
A primary actor trigger an interaction in order to meet some goal; e.g a car owner want his car repaired.
Secondary actors may be involved during the ensuing exchanges: e.g body shop, appraiser, insurance company.
Functions to be performed: actual task; e.g appraise damages; qualification (soft goal), e.g fair appraisal; and resources, e.g premium payment.
The factual description of interactions is both detailed and enriched by elements set within a broader scope:
Goal (strong) dependency: assertions about actual state of affairs: object, activity, or expectations.
Soft-goal dependency: assertions about expected outcomes.
Task dependency: organizational, functional, or technical constraints pertaining to the execution of activities.
Resource dependency: constraints or conditions on the availability of inputs, actual or symbolic.
It would be tempting to generalize the strong/soft distinction to dependencies as to make use of modal logic, strong dependencies associated with deontic rules, soft dependencies with alethic ones. That would .
iStar & Caminao
Since iStar modeling categories are directly aligned with UML Use Cases, they can easily mapped to core Caminao stereotypes for actors, objects, events, and activities.
Interestingly, the iStar strong/soft distinction could translate to the actual/symbolic one which constitute the conceptual backbone of the Caminao paradigm.
From the business perspective, iStar must be credited with two critical tenets:
The focus on interactions between agents is essential for business and system analysts to collaborate. Such benefits appear clearly for the definition of primary and secondary roles (aka actors), intents (business) and capabilities (supporting environments).
The distinction between strong and soft goals, even if the logical basis remains unexploited.
Yet, the system perspective lacks a functional dimension, e.g:
Architecture levels (enterprise and organization, systems and functionalities, platforms and technologies) are not taken into consideration, nor the nature of capabilities, e.g strategic and operational.
The strong/soft dependencies distinction is not explicitly associated with systems capabilities.
On the whole these pros and cons reflect iStar’s declared intent on conceptual modeling; as a corollary these flaws mark also the limits of conceptual modeling when it is detached from the symbolic description of supporting systems functionalities.
Nonetheless, as illustrated by the research quoted below, iStar remains a sound basis for the specification of interactions between users and systems, either as use cases or users’ stories.
The OOAD (Observation, Orientation, Decision, Action) loop is a real-time decision-making paradigm developed in the sixties by Colonel John Boyd from his experience as fighter pilot and military strategist.
The relevancy of OODA for today’s operational decision-making comes from the seamless integration of IT systems with business operations and the resulting merits of agile development processes.
Business: End of Discrete Time-Frames
Business governance was used to be phased: analyze the market, select opportunities, build capabilities, launch operations. No more. With the melting of the fences between actual and symbolic realms, periodic transitional events have lost most of their relevancy. Deprived of discrete and robust time-frames, the weaving of observed facts with business plans has to be managed on the fly. Success now comes from continuous readiness, quicker tempo, and the ability to operate inside adversaries’ time-scales, for defense (force competitor out of favorable position) as well as offense (get a competitive edge). Hence the reference to dogfights.
Dogfights & Agile Primacy
John Boyd train of thoughts started with the observation that, despite the apparent superiority of the soviet Mig 15 on US F-86 during the Korea war, US fighters stood their ground. From that factual observation it took Boyd’s comprehensive engineering work to demonstrate that as far as dogfights were concerned fast transients between maneuvers (aka agility) was more important than technical capabilities. Pushed up Pentagon’s reluctant ladders by Boyd’s sturdy determination, that conclusion have had wide-ranging consequences in the design of USAF fighters and pilots formation for the following generations. Its influence also spread to management, even if theories’ turnover is much faster there, and shelf-life much shorter.
Nowadays, with the accelerated integration of business processes with IT systems, agility is making a comeback from the software engineering corner. Reflecting business and IT convergence, principles like iterative development, just-in-time delivery, and lean processes, all epitomized by the agile software development model, are progressively mingling into business practices with strong resemblances to dogfights; and the resemblances are not only symbolic.
IT Systems & Business Competition
While some similarities between dogfights and business competition may seem metaphorical, one critical aspect is all too real, namely the increasing importance of supporting machines, IT systems or fighter jets.
Basically, IT systems, like fighters’ electronics, are tasked to observe environments, analyse changes in relation to position and objectives, and support decision-making. But today’s systems go further with two qualitative leaps:
The seamless integration of physical and symbolic flows let systems manage some overlapping between supporting decisions and carrying out actions.
Due to their artificial intelligence capabilities, systems can learn on-the-job and improve their performances in real-time feedback loops.
When combined, these two trends have drastic impact on the way machines can support human activities in real-time competitive situations. More to the point, they bring new light on business agility.
As illustrated by the radical transformation of fighter cockpits, the merging of analog and digital flows leaves little room for human mediation: data must be processed into information and presented instantly along two critical dimensions, one for decision-making, the other for information life-cycle:
Man/Machine interfaces have to materialize the merging of actual and symbolic realms as to support just-in-time decision-making.
The replacement of phased selected updates of environment data by continuous changes in raw and massive data means that the status of information has to be incorporated with the information itself, yet without impairing decision-making.
Beyond obvious differences between dogfights and business competition, that double exigence is to characterize business agility:
Instant understanding of changes in business opportunities (Observation) .
Simultaneous assessment of the reliability and shelf-life of pertaining information with regard to current positions and operations (Orientation).
Weighting of options with regard to enterprise capabilities and broader objectives (Decision).
Carrying out of decisions within the relevant time-span (Action).
That understanding of business agility is to be compared with its development and architecture cousins. Yet it doesn’t seem to add much to data analytics and operational decision-making. That is until the concepts of observation and orientation are reassessed with regard to EA maps and territories.
Agility & Orientation: Task vs Tack
To begin with basics, the concept of Orientation comes with a twofold meaning, actual and symbolic:
Actual: a position with regard to external (e.g spacial) coordinates, possibly qualified with abilities to observe, move, or act.
Symbolic: a position with regard to internal (e.g beliefs or aims) references, possibly mixed with known or presumed orientation of other agents, opponents or associates.
When business is considered, data analytics is supposed to deal comprehensively and accurately with markets’ actual orientations. But the symbolic facet is left largely unexplored.
Boyd’s contribution is to bring together both aspects and combine them into actual practice, namely how to foretell the tack of your opponents from their actual tracks as well as their surmised plans, while fooling them about your own moves, actual or planned.
Such ambitions once out of reach, can now be fulfilled due to the combination of big data, artificial intelligence, and the exponential growth on computing power.